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  • INDEX TO THE PHOENICS ENCYCLOPAEDIA
    F G H I J K L M N O P Q R S T U V W X Y Z Preface Entries of especial interest POLIS Home Page In Form data input via formulae MOFOR Moving Frame Of Reference

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_enc/encindex.htm (2016-02-15)
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  • Tr326: VR Object Types and Attributes
    or fixed surface temperature This temperature is set by the user If a weather file is in use the value is taken from the weather file If other thermal conditions are required the ground plane can be turned off and a PLATE object used instead Radiative Heat Loss If the IMMERSOL radiation model is active the domain boundaries can be allowed to exchange heat by radiation with the surroundings If the External radiative link is set to Yes the temperature of the surroundings Texternal can be set The heat flux from the wind profile boundary will then be Q s Text 4 Tp 4 W m 2 GENTRA particle Tracker If the Lagrangian Particle tracker GENTRA is active the domain boundaries will act as particle exits by default This can be switched off Transient operation When a weather data file is not being used the operating time of the WIND object can be set as for most other objects A number of WIND objects can be created with consecutive start and end times each with different flow conditions This way the time variation of wind speed and direction can be accommodated When a weather data file is being used the situation is simpler The date and time chosen represent the time at the start of the calculation The time varying data is extracted from the weather file and is passed to the Earth solver automatically Only one WIND object is needed Initialisation If the initial values for the velocities are all left at their default values of 1E 10m s the WIND object will impose initial conditions based on the chosen boundary layer formula shown below for the WIND PROFILE object If the initial values of the turbulence quantities KE and EP are left at their default values of 1E 10m s the WIND object will impose initial conditions based on the logarithmic profile The values used by the WIND object are echoed to the RESULT file as in this example Wind profile data Up direction Z Inlet density 1 204938E 00 kg m 3 Reference height 1 000000E 01 m Roughness height 1 000000E 01 m Profile type Logarithmic Law Pressure coeff at outflow boundaries 1 000000E 03 Wind direction 9 000000E 01 Wind speed 1 000000E 01 m s Air temperature 2 000000E 01 C Wind Amplification factor When Store Wind Amplification Factor is set to Yes an additional 3D variable called WAMP will be STOREd and the solver will fill it with values of the local air velocity divided by the set wind speed Restrictions The following restrictions apply to the wind object It does not support the multi phase or free surface options The external density is assumed constant but may vary with time if the external pressure and or temperature varies The external temperature is assumed constant with height but may vary with time The velocity always increases with height It only works in Cartesian coordinates The WIND object always fills the entire domain Once the user is certain that it is oriented correctly it can safely be hidden or made wire frame so that it does not obscure the objects within the domain An alternative is to make it not selectable so that the internal objects can be picked from the screen The WIND object can always be selected from the Object Management Dialog Wind Profile IMAGE WIND PROFILE dialog The inlet boundary conditions associated with a wind velocity profile the atmospheric boundary layer can be specified by using a WIND PROFILE object Either a logarithmic or power law velocity profile can be specified as follows U U ln z z o k U U r z z r a and the turbulence quantities are set to k U 2 0 3 e U 3 k z where U is the total velocity at the height z from the ground k is von Karman s constant 0 41 z o is the effective roughness height of the ground terrain U r is the reference velocity at the reference height z r and a is the power law exponent The total friction velocity U is given by U U r k ln z r z o Typical values of the roughness height z o and the power law exponent a are given in the table below Surface type Roughness height z o m Power law exponent a Open flat terrain grass few isolated obstacles 0 03 0 13 Open sea 0 0002 0 16 Low crops occasional large obstacles 0 10 0 16 High crops scattered obstacles 0 25 0 19 Parkland bushes numerous obstacles 0 50 0 21 Suburb forest regular large obstacle coverage 0 50 to 1 0 0 21 to 0 24 The roughness height should not be greater than the height of the first cell centre above the ground as this may lead to numerical problems The reference height z r is usually taken as 10m because this is the height at which mean wind data are generally provided Engineers often prefer to use a power law profile although the log law is to be preferred because it is based on physical laws rather than on an empirical formulation A commonly used empirical relationship between a and z0 is a 0 096 log10 z o 0 016 log10 z o 2 0 24 The height above the ground z is measured from the first open cell in each column of cells This allows the profile to follow the terrain imposed by a blockage IMAGE Wind profile starting over a terrain A density is required to calculate the mass flow rate If the Inlet density is is set to Domain fluid the density will be taken from the formula selected for the domain fluid in the Main Menu Properties panel The density will be calculated from the values set at the boundary location If the fluid entering is not the domain fluid the setting can be switched to User set In this case the required inlet density can be set directly This is the default for complex density relationships Inlet values for solved scalars are set by selecting the scalar with the Setting scalar button then specifying the required inlet value Radiative Heat Loss If the IMMERSOL radiation model is active the wind profile boundary can be allowed to exchange heat by radiation with the surroundings If the External radiative link is set to Yes the temperature of the surroundings Texternal can be set The heat flux from the wind profile boundary will then be Q s Text 4 Tp 4 W m 2 Internal Wind profiles If the wind profile boundary is internal to the domain an extra button appears on the dialog box labeled Object side The settings for this are Low or High and they indicate whether the inflow is to appear on the low co ordinate face or high co ordinate face of the object The flow direction determines whether the boundary acts as a source or sink GENTRA Particle Tracker If the Lagrangian Particle tracker GENTRA is active the wind profile boundary will act as a particle exit by default This can be switched off Restrictions The following restrictions apply to the wind profile object It does not support the multi phase or free surface options The inlet density is assumed constant The inlet temperature is assumed constant The velocity always increases with height a symmetrical profile cannot be made from two opposing wind profile objects It only works in Cartesian coordinates InForm Commands This leads to a dialog from which a selection of InForm commands can be attached to this object It is described in InForm Commands below Fan When located at the domain edges a FAN behaves as an INLET it acts as a source of mass If it is located within the domain it fixes the velocity but does not introduce additional mass it just circulates the fluid already present For multi phase flows Fans at the domain edge must be replaced by INLET objects Fans can only be attached to area objects The default geometry for a Fan is public default cube2t dat a transparent grey rectangle The domain edge Fan dialog box is shown below Image DEFAULT FAN ATTRIBUTES The Nett area ratio sets the ratio between the area actually available for flow sometimes called the effective area and the area used in the model If the ratio is less than 1 the actual injection velocity or volumetric flow rate should be specified for the inlet condition The mass flow will be calculated from area ratio velocity density The Fan can be switched between Velocities and Vol Flow rate as for Inlets A circular fan object can be created by clicking on Change to circular fan with swirl Circular Fans are not available in Cylindrical polar or Body Fitted co ordinates Image CIRCULAR FAN ATTRIBUTES The circular Fan allows for swirl and for an inner radius If the inner radius is zero the entire surface of the Fan is active If it is not zero the Fan becomes an annular Fan with a central hole The swirl direction is set clockwise or anti clockwise looking along a positive co ordinate direction The Swirl Number is the ratio between the tangential velocity and the axial velocity It is the tangent of the Swirl Angle The tangential velocity is taken to be constant across the fan radius The default geometry for a circular Fan is public default cylpipe dat A circular fan forces region boundaries at the axis and at the location of the inner radius giving a 4 4 grid in general If a circular Fan is located internally the areas outside the active zone of the Fan are open to flow If it is necessary to block them an extra object with the geometry public default cylinder dat can be used to fill the central hole and four further objects using public default hh1 dat in appropriate orientations to fill the four corners Image CIRCULAR FAN FILLERS If either Fan type is given a non default geometry the flow conditions will be imposed over those cells covered by the facets of the geometry file If the Lagrangian Particle tracker GENTRA is active Fans can be set to act as particle exits The equivalent internal fan dialogs are shown here Image INTERNAL FAN DIALOGS InForm Commands This leads to a dialog from which a selection of InForm commands can be attached to this object It is described InForm Commands below Outlet Single Phase Multi phase Radiative Heat Loss Internal Outlet InForm An outlet also referred to as an OPENING in Flair is a region of fixed pressure Outlets can only be attached to area objects The flow direction is actually unspecified and depends on local pressure differences although usually the flow will be out of the domain The default geometry for an outlet is public default cube12t dat which represents a transparent light blue cuboid Single Phase The Outlet attributes dialog box is shown below Image SINGLE PHASE OUTLET ATTRIBUTES Acts as Export Import allows the outlet object to behave as a Transfer Object When Export is activated an input box for the export file name appears The default is the current object name At the end of the Solver run the named file is created It will contain the mass flows and other variables for each cell covered by the object If Import is activated the remaining attributes are hidden as the flow conditions will be read from a file The file name can either be entered into the input box or searched for with a file browser The default is also the current object name The Nett area ratio sets the ratio between the area actually available for flow sometimes called the effective area and the area used in the model It is used to deduce the inflow velocity when there is inflow and the external velocity is set to deduced The Coefficient controls how closely the internal pressure matches the set external pressure When the Coefficient is set to Linear the mass flowrate through the outlet is linearly proportional to the pressure difference D P Coef r vel m r vel D P Coef When it is set to Quadratic the mass flow is proportional to the square root of the pressure difference This is appropriate for a known loss coefficient K L D P 0 5 K L r vel 2 m r vel 2 r K L D P 0 5 The loss coefficient K L should be entered directly into the Coefficient input box The external pressure is set relative to a fixed reference pressure The reference pressure is set from the Main Menu Properties panel The external pressure can be the ambient pressure set on the Main Menu Properties panel or any user set value The temperature and velocity values are only used if flow should enter In cells where flow is out of the domain the settings of external values will be ignored They will only be used in those cells where fluid is entering the domain The available settings are In cell and User set For velocity there is an extra option Deduced In cell means that the inflow value will be continually updated to match the currently calculated value in each cell User set allows a known constant value to be set For experienced PHOENICS users In cell is exactly equivalent to COVAL name var ONLYMS SAME at a fixed pressure boundary Deduced means that the in flow value will be deduced at run time from the mass flow rate divided by the in cell density and cell area The rate of change of the deduced velocity can be relaxed to aid stability If VOUT and VOU2 for two phase case is STORE d the deduced velocity is made available for plotting in the Viewer and is printed to RESULT The deduced option is only available for the velocity component normal to the outlet Multi Phase The IPSA outlet dialog box is shown below Image MULTI PHASE OUTLET ATTRIBUTES By default both phases are allowed to pass through The coefficients for the two phases should ideally be in the ratio of the phase densities The default settings are appropriate for phase 1 density of the order of 1 0 and phase 2 density of the order 1000 If only one phase is to be allowed to pass through the coefficient of the other phase should be set to zero to block its passage The Setting values for button sets which phase the external values are being set for If the Lagrangian Particle tracker GENTRA is active Outlets can be set to act as particle exits Radiative Heat Loss If the IMMERSOL radiation model is active the outlet can be allowed to exchange heat by radiation with the surroundings If the External radiative link is set to Yes the temperature of the surroundings Texternal can be set The heat flux from the outlet will then be Q s T ext 4 T p 4 W m 2 where s is the Stefan Boltzmann constant Internal Outlets If the outlet is internal to the domain an extra button appears on the dialog box labeled Object side The settings for this are Low or High and they indicate whether the outlet is to appear on the low co ordinate face or high co ordinate face of the object When inside the domain outlet objects are usually located on the face of a BLOCKAGE They represent the inflow to some ducting that is not being modeled Blockage L H L H X Y or Z If the setting is LOW as on the left side above the outlet acts on the smaller coordinate side of the inlet If the setting is HIGH as on the right side above the outlet acts on the larger coordinate side If the setting is HIGH on the left side or LOW on the right side the outlet acts inside the blockage and nothing happens at all InForm Commands This leads to a dialog from which a selection of InForm commands can be attached to this object It is described in InForm Commands below Angled out An Angled out is a region of fixed pressure The region of influence is the part of the surface of any blockage object s enclosed by the angled out object The angled out object itself must be a 3D volume The flow direction is actually unspecified and depends on local pressure differences although usually the flow will be out of the domain The default geometry for an angled out is public default cube12t dat which represents a transparent light blue cuboid The angled out object may intersect a blockage as shown here IMAGE Angled out intersects blockage It may also completely surround a blockage as shown here IMAGE Angled out surrounds blockage Its area of influence cannot lie on the domain edge as it must intersect a blockage The attributes of the Angled out object are as those of the normal outlet with the addition of Normal velocity to the methods of specifying the external velocity This sets the velocity normal to the surface of the underlying blockage should there be an inflow in any affected cell Sun Dialogs Weather Data Transient operation Absorption of solar radiation by objects Additional output Limitations The SUN object applies the direct and diffuse solar radiation heat load to objects within the domain taking into account Latitude Time of day and time of year Shading from surrounding objects Solar radiation perpendicular to the sun s rays at the top of the earth s atmosphere has an annual mean irradiance of approximately 1370 W m 2 with a seasonal variance of around 3 5W m 2 In passing through the atmosphere part of this energy is absorbed by the atmosphere part is scattered by the atmosphere some back into space and some to the earth the diffuse sky radiation and the remainder direct radiation is transmitted through the atmosphere unchanged There are many sources available from which values of the direct and diffuse radiation may be obtained One such source is the collection of weather data files from the U S Department of Energy freely available as part of the EnergyPlus Energy Simulation Software Weather data for more than 2100 locations are now available in EnergyPlus weather format 1042 locations in the USA 71 locations in Canada and more than 1000 locations in 100 other countries throughout the world The weather data are arranged by World Meteorological Organization region and Country The sun object can use these weather data files directly to obtain the direct and diffuse solar radiation at a particular date and time of day The WIND object can also read the weather data file to obtain the wind speed and direction and the temperature of the air and ground The default SUN dialog is shown here IMAGE SUN dialog Get North and Up from WIND When set to No the user must specify the orientation of the domain relative to North When set to Yes the orientation is shared with the first if more than one WIND object which must have been created already When shared with WIND the input box on the SUN dialog is grayed out and any change in domain orientation must be made on the WIND dialog This ensures that the SUN and WIND are oriented identically eliminating a potential source of error Angle between Y axis and North This works in the same way as for the WIND object It allows the domain to be oriented conveniently with respect to a building or group of buildings IMAGE SUN Object The orange arrow points North When Get NORTH and UP form WIND is set to Yes the orange arrow is not drawn as it is then the same as the WIND s blue arrow In the example below increasing the angle will rotate the North facing axis i e Y clockwise when looking down along the vertical axis i e Z Use weather data file When set to No as shown above the user must supply all the required input data as set out below When set to Yes the input data are taken from an EnergyPlus EPW weather data file The method for doing this is described in the section Loading a Weather Data File The data in the weather file can also be used by a WIND object to supply the inflow outflow conditions at the domain boundaries SUN and WIND always use the same weather file and will use data for the same date and time Latitude This sets the latitude of the location The Equator is at 0 degrees the Northern hemisphere is 0 to 90 at the North pole and the Southern is 0 to 90 at the South pole If a weather file is in use this is set to the value read from the weather file Direct Solar radiation This sets the incident solar radiation in W m 2 In the EnergyPlus data sets this is referred to as the Extraterrestrial Direct Normal Radiation If a weather file is in use this is set to File and the value is taken from the weather file If a weather file is not in use it can be set to Constant or From solar altitude In the latter case the direct solar radiation is obtained from polynomial fits to tables A2 24 direct and A2 25 diffuse of The CIBSE Guide Volume A Design Data These give the following values in W m 2 Solar Altitude degrees Direct Radiation Normal to Sun W m 2 Diffuse Radiation W m 2 Clear Cloudy 5 210 25 25 10 390 40 50 20 620 65 100 25 690 70 125 30 740 75 150 35 780 80 175 40 815 85 200 45 840 90 225 50 860 95 250 60 895 100 300 70 910 105 355 80 920 110 405 90 930 115 455 The solar altitude is obtained from the sun direction vector as calculated either at the start of the run or at the start of each step in a transient Diffuse Solar radiation This sets the diffuse solar radiation in W m 2 If a weather file is in use this is set to File and the value is taken from the weather file If a weather file is not in use it can be set to Constant or From solar altitude in which case values are interpolated from the table above with the solar altitude calculated from the latitude date and time of day The further setting Clear sky or Cloudy sky determines which column to use Date This sets the date Day Month Year at which the sun position is calculated Strictly only the day and month are important If a weather file is in use this entry is taken from the weather file Time This sets the time of day using the 24 hour clock at which the sun position is calculated The time here is in effect local time not taking any daylight saving into account At 12 00 noon the sun is at its highest position If a weather file is in use this entry is taken from the weather file In the image above the large orange ball marks the sun position at the current time of day The small orange balls denote the sun position on the hour during the day and the grey balls at night when the sun is below the horizon The red ball denotes the sun position at midday The orange line drawn from the current sun position to the middle of the ground plane shows the direction of the sun s rays Optional extra output There are several optional settings which can help to show how the model is working These are activated from the Optional extra output dialog Consider the following simple example in which the sun is shining from the front to the back The following 3D variables can be stored SRF this will contain a 1 for all cells identified as either containing a surface or being adjacent to a blockage or plate and a zero for all other cells The cells labeled with a 1 are candidates for being illuminated by the sun Scrutiny of this variable in the Viewer will show if the surface cells are being detected correctly LIT this contains a 1 for surface cells which see the sun and 0 for all others A surface contour of LIT on all blockages with averaging off shows where the sun is shining Scrutiny of this variable in the Viewer will indicate if the illumination is being calculated correctly Note that the detection of illumination is based on cell center coordinates it is possible for the cell centre of a shaded surface to be just visible to the sun In this case check the heat source QS2 as this should be diffuse only in shaded areas There is one cell near the top of the block which appears illuminated but is on the back face of the central block The centre of this cell can still see the sun QS1 stores the actual heat source in Watts for each cell When the IMMERSOL radiation model is active this stores that portion of the heat added to the TEM1 equation QS2 stores the total heat source per unit area for each cell in W m 2 In this image the suspicious cell can be seen to have only the diffuse heat source as the face is pointing away from the sun QS3 when the IMMERSOL radiation model is active this stores that portion of the heat added to the T3 equation The value is a total for each cell in Watts SOL the solar absorption factor specified for each blockage and plate object When plotting these variables in the Viewer it is best to turn the contour averaging off otherwise the averaging process will introduce values of SRF and LIT between 0 and 1 which do not exist The heat sources only exist in a single layer of cells so the averaging will appear to dilute them Transient operation In a transient case the time that should be set is the time at the start of the calculation At each time step the position of the sun will be adjusted and the shading and resulting heat sources recalculated If a weather data file is in use the radiative loads at each time in the data file are passed to the Earth solver The solver will perform a linear interpolation between these values to find the value at the current calculation time If a weather file is not in use the solar radiation can either be a constant or can be derived from the solar altitude as described above The solar altitude will be automatically updated for each time step Further settings Absorption of Solar Radiation by Objects When the SUN object is active an extra input appears on the dialogs of BLOCKAGE PLATE and THIN PLATE objects This sets the amount of incident solar radiation absorbed by that object The default absorption factor is 1 0 i e all the heat is absorbed by the object For most substances absorption is 0 5 or greater bricks weathered steel and marble can be up to 0 9 The exceptions are polished metal surfaces typically 1 2 For participating blockages the solar energy is deposited in the outer most layer of cells in the blockage From there the heat can be conducted away into the center of the blockage as well as being convected and radiated away from the surface For non participating blockages i e those using the 198 or 199 materials and for plates the solar energy is deposited in the layer of fluid cells adjacent to the object Echo of Settings The settings in use by the sun object are echoed into the RESULT file by the solver as shown in this example Solar Heating data Latitude 51 00 Time of day JUN 01 15 00 00 2011 Constant direct solar heating 5 000000E 02 W m 2 Constant diffuse solar heating 1 000000E 02 W m 2 Solar altitude 4 400269E 01 Direct solar radiation 5 000000E 02 W m 2 Diffuse solar radiation 1 000000E 02 W m 2 Limitations The shading calculation is very dependent on there being enough grid to resolve sufficient detail of the geometry If the grid is too coarse the illumination and resulting heat sources will be inaccurate The shading algorithm only works with Z as the UP direction The SUN object always fills the entire domain Once the user is certain that it is oriented correctly it can safely be hidden or made wire frame so that it does not obscure the objects within the domain An alternative is to make it not selectable so that the internal objects can be picked from the screen The SUN object can always be selected from the Object Management Dialog Plate Internal Plate External Plate Radiative Heat Loss InForm Commands Solar Absorption Factor A plate is a blockage which can be treated as having zero thickness This allows for computational efficiency because complete cells do not have to be blocked only cell faces There is no heat transfer by conduction through a plate The default geometry for a plate with no heat sources is public default cube11 dat which represents a brown rectangle Internal Plate The dialog box for an internal plate is shown below Image INTERNAL PLATE Fully blocked Fully blocked Yes is equivalent to an area Porosity set to 0 0 If Fully blocked is set to No the porosity should be set to a value greater than 0 0 and it becomes possible to set an additional pressure drop Image INTERNAL PLATE Partial porosity The velocity used in the pressure drop correlation can be Device Velocity or Superficial Velocity Device Velocity means that the porosity is applied to the flow area so the velocity represents the velocity through the holes in the plate Superficial Velocity means that the porosity is not applied to the flow area and the velocity represents the approach velocity The pressure drop can be calculated from the expressions None no imposed pressure drop Velocity squared D P 0 5 Coef density Vel 2 Pa Power of Velocity D P Coef Vel n Pa Linear in velocity D P Coef Vel Pa CIBSE Guide expression for perforated plate Pa CIBSE Guide expression for wire mesh Pa where Coef is the Resistance Coefficient set for the object The CIBSE Guide correlations for a perforated plate and for wire mesh use formula 2 above with the following values for the resistance Coefficient Free area ratio Coef plate Coef Mesh 0 2 51 0 17 0 0 3 18 0 6 2 0 4 8 3 3 0 0 5 4 0 1 7 0 6 2 0 1 0 0 7 1 0 0 6 0 8 0 4 0 3 In addition heat transfer and wall friction parameters can be specified for either side of an internal plate using the Low side parameters High side parameters buttons Image HIGH SIDE PARAMETERS The default roughness takes the equivalent sand grain roughness height for the logarithmic wall functions or the roughness height for the fully rough wall functions from the value set in the Main menu Sources panel WALLA in Q1 The alternative is to set a specific value Image HIGH SIDE PARAMETERS user set roughness The default wall function coefficient is that set in the Main menu Sources panel WALLCO in Q1 Alternatively it can be chosen from this list Image List of wall functions If a Wind or Wind profile object is also being used the wall function on any plate used to represent the ground should be set to Fully rough and the roughness height set to the same value as was used for the wind velocity profile The energy source is specified in the same way as on a blockage and can be different on either side of the plate Note that the volume terms appearing in the blockage heat source expressions are all replaced by area Once a heat source has been set on either side the default geometry is changed to public default cube13 dat an orange rectangle The Slide Velocity settings allow the velocity of the surface of the plate to be set External plate Plates on the outer edges of the solution domain only have the Roughness Wall function Energy Source and Slide Velocity settings it is not possible to set a porosity at the domain boundary Image EXTERNAL PLATE Radiative Heat Loss If the IMMERSOL radiation model is active the surface emissivity for either side of the plate can be set An external plate with IMMERSOL allows an extra energy source Radiating Solid This gives a heat source containing convective and radiative parts with the form Q a b T ext T p c d T ext 4 T p 4 W m 2 where a represents a constant heat flux W m 2 b represents a heat transfer coefficient in W m 2 K c c represents a power d represents the surface emissivity Stefan Boltzmann constant T ext represents the external temperature InForm Commands This leads to a dialog from which a selection of InForm commands can be attached to this object It is described in InForm Commands below Solar Absorption Factor When a SUN object is active an additional input box appears in which the fraction of the incident solar radiation absorbed by this object can be set The default absorption factor is 1 0 i e all the heat is absorbed by the object For most substances absorption is 0 5 or greater bricks weathered steel and marble can be up to 0 9 The exceptions are polished metal surfaces typically 1 2 For internal plates absorption factors are specified for each side of the plate Thin Plate This is similar to the PLATE type except that heat transfer through the plate is allowed A notional thickness and material type are specified but these are only used for the calculation of thermal resistance The object must be an area Thin plates are only allowed within the domain but not at the edges The default geometry for a Thin Plate is public default cube11 dat a brown rectangle The Thin Plate dialog box is shown below Image FULLY BLOCKED YES If Fully blocked is changed to No the porosity can be set to be greater than 0 0 Image FULLY BLOCKED NO The velocity and pressure drop formulations are as for the PLATE object If the Energy Equation is on the initial temperature of the plate can be set If the IMMERSOL radiation model is on the surface emissivity for either side of the plate can be set Solar Absorption Factor When a SUN object is active an additional input box appears in which the fraction of the incident solar radiation absorbed by this object can be set The default absorption factor is 1 0 i e all the heat is absorbed by the object For most substances absorption is 0 5 or greater bricks weathered steel and marble can be up to 0 9 The exceptions are polished metal surfaces typically 1 2 Separate absorption factors are specified for each side of the thin plate Foliage This object type is used to model the interaction between the wind and forested areas as well with other types of tree or plant canopy such as for example urban plantings of avenues or clumps of trees From an aerodynamic perspective the main impact of vegetation on the environment is the reduction in air velocity due to drag forces and the additional

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  • TR326: Importing CAD Data
    dialog has been clicked a confirmation of the input and output file names will be shown If happy to proceed click OK and the selected file will be translated using the DatMaker module The options for DatMaker are as follows Do Hole Mend the facets defining the shape of an object should make a complete closed volume This attempts to identify any missing facets and to fill the resulting hole with new facets Check Folds sometimes the facets in a geometry may be folded over each other leading to problems in detection at the solution stage This attempts to identify such facets and replaces them with unfolded facets Check consistency the facets making up a closed volume must all face outwards Sometimes some facets point inwards again leading to detection problems This attempts to ensure that all facets point the same way and that all point outwards No graphic output when ticked by default DatMaker runs silently with no user input When un ticked DatMaker will open a graphics window once conversion is complete allowing the original and converted geometries to be inspected before import to VR Editor Split CAD file into separate closed volumes when ticked each closed volume found in the original CAD will be output as a separate DAT file This may result in many hundreds of files being created Split CAD file into separate CAD entities when ticked each named entity found in the original CAD file will be output as a separate DAT file Each of these may contain more than one closed volume The last two options are mutually exclusive In either case the names of the output files will be based on the original CAD file name with 1 dat 2 dat n dat added to the end In addition a file with a name ending 0 dat will also be created This file marks the original orign and extent of the single CAD file It is used as a place holder to ensure the separate files are imported in the correct locations relative to each other Note that the more repair processing is selected the longer the repair may take Fitting the CAD Geometry to the Object Once the translation is complete the following dialog box will be shown This dialog shows how many points and facets were created and shows the size and origin read from the CAD file There are then two choices for the size and position Object Size Take size from Geometry file No Scale the geometry so that it fits within the bounding box of the current object This is the default option illustrated in the previous image Yes Take the size of the object from the CAD geometry and resize the object bounding box to fit If necessary resize the domain to encompass the object Object Position Take position from Geometry file No Leave the position as it is This is the default option illustrated in the previous image Yes Take the position of the object from the CAD geometry and reposition the object so that it takes on the location read from the CAD file If necessary resize the domain to encompass the object Whichever option is chosen the size and location of the object can be changed as desired later If the non default second options are selected by clicking on the No buttons to change them to Yes the dialog changes to this The object will be re sized to the dimensions found in the CAD file and placed at the location found in the CAD file If the re sized object does not fit inside the solution domain the solution domain is re sized to just encompass the new object Clicking on Reset Fit to Window on the toolbar will rescale the view to show the entire domain If the Object constrained by domain tickbox on the General page is cleared before importing the CAD file or Object constrained by domain is set to No on the dialog the domain will not be resized if the object becomes bigger than the domain Co ordinate System Origin The data entry boxes labeled Xorg Yorg and Zorg are used to locate the origin of the PHOENICS co ordinate system relative to the CAD system In the CAD system it is often possible to locate geometries in the negative quadrants In PHOENICS VR only positive co ordinates are allowed unless the Object constrained by domain tickbox on the General page is cleared Even then the solution only takes place in the positive quadrant The values specified for Xorg Yorg and Zorg are used to shift the object into the required position in the PHOENICS co ordinate system The relationship used is of the form Xp VR Xp CAD Xorg Yp VR Yp CAD Yorg Zp VR Zp CAD Zorg Example 1 consider an object located at 10 20 0 in the CAD system In the CFD simulation this object is to be located at 5 10 0 The required settings for Xorg Yorg and Zorg are 15 30 and 0 respectively Example 2 consider an object located at 10 20 0 in the CAD system In the CFD simulation this object is to be located at 5 10 0 The required settings for Xorg Yorg and Zorg are 5 10 and 0 respectively If Object constrained by domain is set to No and Take position from geometry file is set to Yes the object will be positioned exactly as in the CAD file without using the offset values If the PHOENICS origin in CAD system is At object position as shown in the image the input boxes are greyed out Xorg Yorg and Zorg are set equal to Xp CAD Yp CAD Zp CAD for the first object to be imported This ensures that the the first object is placed at the PHOENICS origin Subsequent objects will be placed relative to the first Thus if the objects referred to in Examples 1 and 2 above

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_docs/tr326/cadimprt.htm (2016-02-15)
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  • Tr313: FLAIR User Guide
    deflection from the normal to the plane of the diffuser in each of the other two directions If the plane is The default value of 0 0 means no deflection the flow comes out normal to the diffuser surface Positive values mean deflection in the axis direction negative values mean deflection in the axis direction The deflection is limited to 89 degrees When the Symmetric Yes No switch is set to Yes the flow is divided symmetrically in the positive and negative axis directions It is as if the grille were made up of two grilles with opposite deflection angles When set to No both halves use the same deflection angle As the grille is divided horizontally and vertically there are actually four sources for each grille Effective area ratio for displacement type only For a displacement diffuser this is the ratio between the true flow area and the modeled area It is the same for all active faces 3 1 2 Fire The fire object is used to create an area or volumetric heat source representing a fire There are several options for setting the heat mass and smoke sources at the fire It is assumed that the mass released by the fire is the products of combustion and that the SMOK variable represents the local mass fraction of combustion product Some combinations require the Heat of Combustion Hfu and the stoichiometric ratio Rox to be set If the product mass fraction SMOK is solved these values are set in Main menu Solve smoke mass fraction settings If SMOK is not solved these settings can be made on the Fire object dialog The fire can be loaded through the Object management in the same way as described in section 3 1 1 above for the diffuser The default fire object and its attributes are shown in figure 3 11 below Figure 3 11 The fire and its default attributes The dialog will change as different options are selected showing input boxes for the various parameters Heat Source The heat source set here is the total heat source Q t Q convective Q radiative If the radiation model is not active the heat source reported in the solution as Source of TEM1 is reduced by the Radiative fraction R f to be just the convective part The Radiative factor is set on the Smoke settings panel of the Main Menu and is defaulted to 0 3333 The total heat release rate is still used to derive the smoke mass source The options for the Heat source are Figure 3 12 Fire heat sources Mass related the rate of heat release is a function of the mass release rate Q t mass Heat of Combustion 1 R ox If the Heat of Combustion is not constant use From table file for both the heat and mass sources Fixed Temperature the temperature at the fire location remains fixed Fixed Power the heat release rate in W remains fixed Linear with Temperature the heat release rate is a linear function of the average temperature in the fire Q t a b T TEMP0 where TEMP0 is the reference temperature If T is below Tmin or above Tmax these values are used in the formula Power of Time the heat release rate in Watts varies as time raised to a power Q t min Q max a t t 0 b where Q max is the maximum permitted heat release rate t 0 is the time at the start of the fire and a and b are constants It has been found that the heat release rate grows approximately as the square of the time i e the b constant above is 2 0 Characteristic growth times and constants for various classes of fire are given in Table 10 1 of the CIBSE Guide E Fire Engineering Ref 4 Fire class Characteristic growth time s Constant a W s 2 Ultra fast 75 187 6 Fast 150 46 9 Medium 300 11 7 Slow 600 2 9 Piece wise Linear in time the heat release rate in W varies linearly with time over set time periods Up to 10 time intervals can be specified over the duration of the fire Within each time segment the heat source is Q t Q n 1 t t n 1 t n t n 1 Q n Q n 1 From table file the total heat release rate in Watts as a function of time is read from a file containing a table of values The file must contain two columns The first column is the time in seconds the second is the total heat release rate in Watts An example might be Time Qt 0 0 60 350000 120 700000 180 1050000 240 1400000 300 1400000 360 1400000 420 1400000 480 1400000 540 1400000 600 2055000 The Earth solver will perform a linear interpolation in the table to find the heat source for any particular time The time in the table is the time since ignition This option allows for any number of points in the table and should be used in preference to Piece wise Linear in time if there are more than 10 points In a transient case a file called heat sources csv will be created It will contain the convective heat source for each fire object for each time step An example is given here Time FIXMAS POOL PWLM FIXT FIXQ LINTEM 3 000E 01 1 100E 05 7 705E 05 1 719E 03 0 000E 00 1 320E 06 1 005E 05 9 000E 01 1 100E 05 1 346E 06 5 156E 03 2 747E 05 1 320E 06 1 005E 05 1 500E 02 1 100E 05 2 011E 06 8 594E 03 2 747E 05 1 320E 06 1 005E 05 2 100E 02 1 100E 05 2 753E 06 1 203E 04 2 747E 05 1 320E 06 1 005E 05 2 700E 02 1 100E 05 3 561E 06 1 547E 04 5 493E 05 1 320E 06 1 005E 05 The first column is the solver time at the mid point of each time step The subsequent columns are the heat release rates in Watts for the FIRE objects named in the first row Mass Source The options for the Mass source are Figure 3 13 Fire mass sources The mass released is taken to be the products of combustion 1kg Fuel R ox kg Oxygen 1 R ox kg Product No Mass Source the fire is a source of heat and possibly smoke only Heat Related the mass source is deduced from the total heat source by dividing by a heat of combustion Mass Q t 1 R ox Heat of Combustion If the Heat of Combustion is not constant use From table file for both the heat and mass sources Fixed Mass Source the mass source in kg s is fixed for the duration of the fire POOL Fire the mass source in kg s is calculated from the nominal area of the fire as a function of time t Area a b t c Mass Area 1 exp B Area 5 Piece wise Linear in time the mass source in kg s varies linearly with time over set time periods Up to 10 time intervals can be specified over the duration of the fire Within each time segment the mass flow is Mass M n 1 t t n 1 t n t n 1 M n M n 1 From table file the product mass release rate in kg s as a function of time is read from a file containing a table of values The file must contain two columns The first column is the time in seconds the second is the product mass source in kg s An example might be Time Mass 0 0 60 0 0073 120 0 0219 180 0 0365 240 0 051 300 0 0583 360 0 0583 420 0 0583 480 0 0583 540 0 0583 600 0 072 The Earth solver will perform a linear interpolation in the table to find the mass source for any particular time The time in the table is the time since ignition This option allows for any number of points in the table and should be used in preference to Piece wise Linear in time if there are more than 10 points In a transient case a file called smoke sources csv will be created It will contain the product mass smoke source for each fire object for each time step An example is given here Time FIXMAS POOL PWLM FIXT FIXQ LINTEM 3 000E 01 2 000E 02 1 401E 01 3 125E 04 8 182E 05 2 400E 01 1 828E 02 9 000E 01 2 000E 02 2 446E 01 9 375E 04 8 182E 05 2 400E 01 1 828E 02 1 500E 02 2 000E 02 3 656E 01 1 562E 03 8 182E 05 2 400E 01 1 828E 02 2 100E 02 2 000E 02 5 005E 01 2 187E 03 8 182E 05 2 400E 01 1 828E 02 2 700E 02 2 000E 02 6 474E 01 2 812E 03 8 182E 05 2 400E 01 1 828E 02 The first column is the solver time at the mid point of each time step The subsequent columns are the mass release rates in kg s for the FIRE objects named in the first row Scalar Source The options for the Scalar source are Figure 3 14 Fire smoke sources The SMOK scalar is taken to be product of combustion the inlet value is therefore always 1 0 The parameters determining how the smoke concentration affect visibility are all set in Main menu Solve smoke mass fraction settings No source There is no associated scalar source Mass related the rate of scalar release is linked to the mass release rate Heat related the rate of scalar release is linked to the heat release rate A mass source is deduced from the heat release rate using the expression mass Q t 1 R ox Heat of Combustion This is then used to set the scalar source Fixed Value the scalar value at the fire location remains fixed Note that some of the source types are only available for transient simulations Not all source types are mutually compatible for example if the mass source is heat related the heat source cannot be mass related Such incompatible combinations will be flagged up as errors when trying to set them InForm InForm sources are set through the InForm Commands button This leads to a dialog from which a selection of InForm commands can be attached to this object It is described here 3 1 3 Jetfan The jetfan object is used to create a volume of fixed velocity representing the effects of a jetfan The velocity components in the domain X Y and Z axes are calculated internally to give the set total velocity and direction The jetfan can be loaded through the Object management in the same way as described in section 3 1 1 above for the diffuser The default jetfan object and its attributes are shown in figure 3 15 below Figure 3 15 The jetfan and its default attributes Fan type The fan can be rectangular or circular in cross section Unless the grid is very fine the difference will be mainly visual Xpos Ypos Zpos Sets the location of the centre of the jetfan object Any rotations set will be about this point Length Sets the length of the jetfan in the X co ordinate direction of the jetfan Width Sets the width of a rectangular jetfan in the Y co ordinate direction of the jetfan Depth Sets the depth of a rectangular jetfan in the Z co ordinate direction of the jetfan Diameter Sets the diameter of a circular jetfan Velocity Sets the delivery velocity of the jetfan in the X co ordinate direction of the jetfan The jetfan always blows along its own X axis The jetfan can be rotated about its centre to point in any desired direction Set turbulence intensity when Yes sets the turbulence intensity for the jetfan Typical values may be in the range 20 25 The turbulence quantities are set from KE jet Intensity 100 Velocity 2 EP jet 0 1643 KE jet 3 2 0 1 diameter For a rectangular jetfan the diameter is taken as 0 5 Height Width When No the jetfan has no direct impact on the turbulence field other than by creating additional velocity gradients The default setting is No When switched to Yes a value of 22 is set Heat load Sets the heat gain or loss through the jetfan The default setting of 0 0 ensures there is no heat gain or loss Positive values represent a heat gain as through a heater negative values represent a loss as through a cooler Angle to X axis Sets the inclination of the jetfan X co ordinate to the domain X axis The resulting flow direction is as shown in the table below Angle Jet direction 0 X 90 Y 180 X 270 Y Angle to Z axis Sets the inclination of the jetfan X co ordinate to the domain Z axis The default angle of 90 directs the jet parallel to the floor Angles 90 incline the jet towards the floor angles 90 incline the jet towards the ceiling 3 1 4 Spray head The spray head is the sprinkler designed for fire extinction It works with the GENTRA module see Encyclopaedia in POLIS The spray head can be loaded through the Object management in the same way as described in section 3 1 1 above for the diffuser The default spray head object and its attributes are shown in figure 3 16 below Figure 3 16 The default spray head object The following specifications can be defined in the attributes dialog box Spray axis direction This sets the axis of the spray to be along the positive X Y or Z axis The spray head disk is normal to the selected axis Spray position This sets the location of the centre of the spray head disk The disk is always normal to the spray axis Spray radius This sets the radius of the spray head disk The droplet injection ports are uniformly distributed along the circumference of the disk Number of ports This sets the number of the injection ports around the circumference of the spray disk Total volume flow rate This sets the total volumetric flow rate of the water to be injected from the spray The total amount is divided equally among the injection ports The units are always litres second Total injection velocity This sets the velocity with which the droplets are deemed to be injected Spray angle from spray axis This sets the angle between the spray and the spray axis When set to 0 0 the droplets will be injected in the direction of the positive spray axis Usually this will mean vertically upwards When set to 90 the droplets will be injected normal to the axis Usually this will mean horizontally When sets to 180 the droplets will be injected in the direction of the negative spray axis Usually this will mean vertically downwards Injection temperature This sets the temperature of the injected droplets The units are always degree C Volume median diameter 50 of the water by volume is contained in droplets of this or greater diameter Other 50 is contained in smaller droplets Number of size ranges This sets number of droplet size to be considered When sets to 1 the droplets will take volume median diameter When sets to greater than 1 the sizes used will lie between the set minimum and maximum values and will be distributed according to the Rosin Ramler droplet distribution function Calculate link temperature appears for transient run only This determines whether the link temperature for the spray will be calculated or not If Calculate link temperature is set to Yes then two more entries Activation temperature and Response time Index will appear The Track start and end times will be reset to Auto on and a new data entry box will appear for setting the duration of the spray after initiation Activation temperature is the temperature at which the track is to start Response Time Index RTI is a measure of the detector sensitivity The link temperature is calculated from 17 dT l dt e Vel T g T l RTI where T l is the link temperature Vel is the gas velocity and T g is the gas temperature The calculated link temperatures are written to the file tlink1 csv at the end of each time step If there are more than 20 sprays each group of 20 will be written to a separate tlinkn csv file where n is 1 2 3 etc A tutorial is provided in section 6 9 which shows how to use the Spray head object for the simulation of fire extinction If GENTRA is not active at the time the first spray head object is created it will be automatically turned on with all settings made for the spray model Only the spray start and end times need be set for a transient case should the spray not be active all the time If GENTRA is already turned on it will be assumed that all settings as correct and no default settings will be made The settings made for GENTRA are Particle type Vaporising droplets all properties at default water Inlet data file SPIN This file will be created automatically Wall obstacle treatment Remove particle 3 1 5 Person The Person object represents the heat load effect of a single human being It does not apply a resistance to motion Figure 3 17 The default Person object The Posture button allows a choice of Standing as in the image above Sitting or User If User is selected the Size and Position dialogs on the Object Specification dialog can be used to size and rotate the image The Facing button toggles through X X Y and Y to determine which direction the person faces The heat source can be Total heat in W of fixed temperature in Centigrade 3 1 6 People The People object is used to represent the heat load of a large number of people for example the audience in a theatre It does not apply a resistance to motion Figure 3 18 The default People object 3 2 The HVAC specific objects and their default attributes The predefined HVAC specific object files contain both geometry information and the default attributes of the object or assembly They are stored in the directory phoenics d satell d object public flair and its subdirectories as described below 3 2 1 Cabinets subdirectory contains the following object files Casing is an assembly of seven components three thin plates and four plates as shown in figure 3 19 Figure 3 19 The casing assembly A double click on each component brings up the object specification dialog and then a click on Attributes button brings up the panel showing that the material of all the thin plates and the plates as shown in figure 3 20a and figure 3 20b respectively Figure 3 20a The default attributes of the thin plate of the casing assembly Figure 3 20b The default attributes of the plate of the casing assembly The user can scale the casing assembly and place it in a desired location or modify the attributes of individual components It is also possible for the size and the location of individual component to be modified if the component is disconnected from the assembly RackUnit is an assembly of four components a blockage and three inlets as shown in figure 3 21 Figure 3 21 The rackunit assembly The default attributes of the individual inlets are shown in figure 3 22 a c respectively Figure 3 22a The default attributes of an inlet of the rackunit assembly Figure 3 22b The default attributes of an inlet of the rackunit assembly Figure 3 22c The default attributes of an inlet of the rackunit assembly 3 2 2 Jetfans subdirectory contains the following model files fan x20 pob is an assembly consisting of 5 components a fan and 4 plates forming a duct as shown in figure 3 23 Figure 3 23 The Fan x20 assembly The internal fan is located in the middle of the duct and its attributes are shown in figure 3 24 Figure 3 24 The attributes of the fan fan x20 pob is the same as fan x20 pob except for the X direction velocity which is set to 20m s 3 2 3 Living subdirectory contains the following model files sitting man pob is a single object file and is used to set the heat source for a sitting man as shown on the left in figure 3 25 The material of the sitting man is the domain material and its default attributes are shown in figure 3 26 Figure 3 25 The sitting man and the standing man Figure 3 26 The attributes of the sitting man standing man pob is shown on the right in figure 3 25 and its default attributes are the same as those for the sitting man except for the dimensions 3 2 4 Perforated Plates subdirectory contains perfplate pob is a single object plate and its default attributes are shown in figure 3 27 below Figure 3 27 The default attributes of the perforated plate 3 3 How to import the HVAC objects 3 3 1 Using the Object Management dialog box Click Object button on the Main controls the Object management dialog box will appear on the screen as shown in figure 3 28 Figure 3 28 The Object Management dialog box Click Object pull down menu Object on the Object Management The selection of New and Import will bring you straight to the prepared HVAC data base as shown in figure 3 29 Figure 3 29 The Import Object dialog box All the object files pob file are kept in the directory d object public flair and its subdirectories The supplied objects are divided into a number of classes with fairly self explanatory names for example a casing can be found in flair cabinets directory Enter the directory and select the desired object then a click on Open brings up the dialog box shown in figure 3 30 which allows the user to define the position of the selected object relative to the domain origin 0 0 0 Figure 3 30 The default position of the selected object If the origin defined is outside the domain bounding box the domain size will be automatically stretched to be big enough just to catch the object sitting at the domain edge The user might have to click Reset button on the movement control panel and then click Fit to window in order to bring the whole picture back to the screen Once the user has clicked OK the selected object will appear on the screen and at the same time the object specification dialog box shown in figure 3 31 with the default of General will also appear on the screen which enables the user to continue his settings Figure 3 31 The object specification dialog box 3 3 2 Object attributes For a single object simply click on the Attributes button on the General dialog box and an object attributes dialog box will appear on the screen For an assembly object the user needs to click on Name to select a component of the assembly object and the user can examine or modify the default attributes as shown in figure 3 32 for the component B4 of the casing assembly Figure 3 32 The object attributes dialog box 3 3 3 Exporting an Object Clicking on the Export button brings up the dialog box shown in figure 3 33 which is used to export an object file The user has the options to save the attributes or the geometry data or both The user has the browser to find the directory where he puts the object file otherwise the object file will be in your working directory Figure 3 33 The object export dialog box 3 3 4 Object sizing scaling and positioning The Size button is used to check the size of the imported object and then scale or re size it The Place button is used to see the position of the imported object and re position or rotate it about its own axis 3 3 5 Object Colouring and Rotation options The Option button is used to change the colour of the imported object and to choose the rotation centre and rotation mode 3 3 6 Import custom geometry The Shape button is used to import custom shapes as follows Geometry enables the user to import a geometry from the supplied geometry library Import geometry from Shapemaker enables the user to import a geometry from Shapemaker Tutorial 5 A room with sunlight in section 6 5 shows how to use Shapemaker to create a sunlight object loaded into FLAIR VR Editor for the model building Import CAD geometry from STL or DXF file enables the user to import CAD files from STL or DXF file Tutorial 8 How to import STL file in section 6 8 shows how to import STL geometry files The detailed operations about how to import custom geometry can be found in PHOENICS documentation Tr326 4 HVAC Related Models As a special version of PHOENICS FLAIR has the following HVAC related models system curve fan operating point humidity calculation comfort index and smoke movement This chapter is to provide detailed descriptions about how to activate these models All these models can be set up through the Main Menu in FLAIR VR Editor The main menu is reached by clicking the Main Menu button on the hand set This brings up the Main Menu top panel 4 1 Main Menu Top Panel Figure 4 1 is the top panel of the main menu and can be reached from any other panel by clicking on Top menu It is the panel displayed whenever the Main menu is activated from the hand set of the FLAIR VR Editor Figure 4 1 Main menu top panel The buttons along the top of the panel allow the setting and modification of the case Some of those buttons have been used for the simple example described in section 2 3 above and more buttons will be used in Chapter 6 Tutorials a complete description of functions for each button can be found in PHOENICS documentation TR326 This section only describes the parts of the Models panel specific to Flair Figure 4 2 The Models panel System curve Fan operating point Solve pollutants Solve smoke mass fraction Solve Specific Humidity Comfort Indices Radiation 4 2 System curve During the design stage it may be useful to know the system characteristic in order to be able to choose the appropriate Fan for the equipment If you set the System curve button to ON Settings button will appear The Settings dialog box is shown in figure 4 3 which enables you to perform simulation of the flow through your system using different flow rates and obtaining several pairs of data flow rate vs pressure drop allowing you to plot the system curve Figure 4 3 The System curve dialog box The Settings allow the user to specify the minimum flow rate in m 3 h through the system for which the user want to obtain pressure drop Note that minimum value is 1 0 If the user has provided for two or more fans the flow rate should be specified the total for all fans the maximum flow rate in m 3 h through the system The number of points between minimum and maximum values of the flow rate The overall number of points is the number the user enters plus 2 The number of iteration for each flow rate FLAIR initially sets at least 500 iterations for each flow rate The user may overwrite this number using the Numerics control option from the Main menu penal A smaller number may produce less accurate results The file hotdata generated at the end of the system curve calculation will provide information about how well results have converged The user may also find extracted data and a line printer plot of the curve in their result file Note that Fan setting cannot be active at the same time as system curve calculation therefore if when the user activates system curve Fan setting is active it will automatically become de activated 4 3 Fan operating point Although the user can specify a constant total mass flow rate in FLAIR in real world applications the performance of a fan is described by its characteristic curve The relationship between volumetric flow rate and the pressure drop across the fan static pressure is described by the fan characteristic curve which is usually supplied by the fan manufacturer as shown in figure 4 4 The total volumetric flow rate is plotted against fan static pressure Figure 4 4 An example of the Fan flow characteristics If your requirement is to choose the fan which will be appropriate for the equipment you are designing you may need to perform system curve simulation see section 4 1 1 in order to obtain the system characteristics which would then be used to determine the fan operating point which occurs at the intersection of the system curve with the fan characteristic curve The Fan operating point option in Models menu in FLAIR automates this procedure you are only required to specify the fan characteristic curve in tabulated form and FLAIR will calculate the operation point When the Fan operating point option is activated FLAIR will compute the fan operating point for a given fan characteristic curve using an iterative method as follows Take an internally determined initial value of flow rate according to the flow rate range of the given fan type In this respect FLAIR will ignore any initial flow rate or velocity assigned to the fan by users In the calculation a constant velocity corresponding to the given flow rate is assumed over the area of the fan For an internal fan an averaged pressure difference between the front cell centres and the rear cell centres of the fan will be constructed and for the fan at a boundary of the domain the averaged pressure difference is calculated between the cell centres immediately adjacent to the fan and the outside which is default assumed zero pressure This pressure difference is different from the static pressure extracted from the fan characteristic curve at the same volume flow rate when the simulation is not convergent FLAIR will try to reduce the difference using an adjusted flow rate according to the fan flow characteristic curve Repeat step 2 until the simulation is convergent and then the fan operating point is found This option works in the same manner for a single fan and for multiple fans each having different characteristic curve Fans in parallel are treated as separate fans with the combined characteristics of each fan Fans in series are treated as a single fan with the combined characteristics At the end of the result file you will find information about the operating point of your fan system combination Note that fan setting cannot be active at the same time as system curve calculation therefore when you activate fan setting if system curve is active it will be automatically de activated At least one FAN object must exist before this option can be activated How FLAIR stores the fan flow characteristic curve The fan flow characteristic curve is stored in a file called FANDATA The file can contain information for up to 50 fans The format for each fan is Fan title up to 16 characters Number of data pairs for the fan single integer up to 100 Two columns of numbers first column is flow rate in m 3 h and second column is pressure drop in Pa Example of Fan data FAN1 5 0 8 30 6 60 4 90 2 120 0 It shall reside in the current working directory When Fan operating point is active a Settings button appears which leads to this page Figure 4 5 The Fan Operating Point Settings panel The Edit button opens the fandata file with the current file editor If there is no fandata file in the current working directory the default file is copied in from phoenics d earth d spe d hotbox inplib Any further fan specifications can now be added following the format given above The Add button shows a list of fans which are not included in the matching and allows the selection of a fan from the fandata file The remove button allows selected fans to be removed from the matching They will then operate at their set flow rates The List button gives a list of fans included in the matching together with the selected fan type The Show button shows a list of all the currently defined fan objects To use the Fan Operating point option you need to do the following Create at least one Fan object using the Object Management dialog box If necessary modify the fandata file in the working directory to include any specific fans required The form of the fandata file is as exemplified above The fandata file can be edited from the Main Menu Models panel Create further fan objects as required In section 7 6 there is a tutorial example which provides step by step instructions on how to activate the Fan Operating Point option for a single fan mounted at a boundary of a cabinet 4 4 Solve pollutants The Solve pollutants Settings button leads to the following panel Figure 4 6 The Solve Pollutants Settings panel This panel allows up to five additional concentration equations to be solved These can represent whatever the user wishes often they will be concentrations of a pollutant species perhaps CO released from vehicle exhausts The names of these variables are at the user s choice up to four characters The default names are C1 C2 C3 C4 and C5 When activated each variable is set to be solved using the whole field solver use linear relaxation of 0 5 have limits between 0 0 and 1 0 have initial values of 0 0 have external values at inlets and openings of 0 0 All of these can be changed later The nominal units of these equations are kg kg mixture but they can represent a wide range of quantities Note that the first pollutant is the C1 variable used in the Ideal Gas Law with mixture gas Constant available for the gas density from the Properties panel If the Include in gas density calculation button is set to YES the dialog changes to that shown in Figure 4 6a Figure 4 6a The Solve Pollutants Settings panel The molecular weight of each species and that of the carrier fluid can now be set These will be used to calculate a mixture molecular weight which is then used in the Ideal Gas Law to obtain the fluid density The mixture molecular weight is placed in the STOREd variable GMIX for plotting in the Viewer The formula used to obtain the mixture molecular weight is GMIX M c 1 n C i n M i C i where M c and M i are the molecular weights of the carrier and species respectively The density is then calculated from r P1 PRESS0 GMIX 8314 46 TEM1 TEMP0

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  • Implementation of SPINTO
    so perhaps to conform with the bounding boxes of VR objects In this case he should make the next sequence of operations Prepare a first Q1 file with finest grid and LSWEEP 2 Run the satellite and earth modules A phi file will thus be created and also a pbcl dat file This should be stored for later use Prepare a q1spin file containing the lines SAVEFINE STOP Run SPINTO thereby creating files FINE grd and FINE q1 However no NPHI file will be created File FINE grd contains finest grid File FINE q1 is copy of current Q1 Prepare a second q1spin file containing the next lines COARSE X 2 COARSE Y 2 COARSE Z 2 SAVEGRD COARSE STOP Run SPINTO which will then create the files COARSE grd and COARSE q1 File COARSE grd contains a coarsened grid File COARSE q1 corresponds to the coarsened grid and sets PARSOL F Copy COARSE q1 to q1 Run satellite and earth File phi will be created with results on the coarsened grid Prepare a third q1spin file containing the lines lines USEGRID FINE STOP Run SPINTO File NPHI will be created with fields which are interpolated on finest grid The user should copy NPHI to PHI Copy FINE q1 to q1 and add statement RESTRT ALL or more correctly RESTRT list of solved variables Run satellite and earth File phi will be created with outcomes on fine grid 3 4 A script for Method 1 It would be tedious and error prone for the user to carry out all the above steps and for each new calculation Therefore all the operations have been coded into the WINDOWS DOS script SPINTO BAT This will now be presented and commented upon REM The purpose of the script is to enable the advantage gained from the REM use of SPINTO to be established by obtaining first a non SPINTO REM solution corresponding to a single restart and therefore a total REM number of sweeps equal to 2 SWEEPS with the solution obtained after REM SPINTO using sequence in which PARSOL T only for the finest grid run REM This file simple bat organises a series of runs in which a coarse grid REM is refined twice for a Q1 in which there are facetted objects in the REM domain and PARSOL t REM Parsol is set f for all the coarser grid runs REM REM LSWEEP is set equal to the environment variable SWEEPS for all runs REM the runs are REM 1 finest grid parsol t lsweep 2 so as to create pbcl dat REM This may be omitted if facetted objects are absent or if parsol has REM been set f in the original q1 REM 2 coarsest grid parsol f REM 3 SPINTO restart from run 2 finer grid 2 in all directions parsol f REM 4 SPINTO restart from run 3 finest grid 2 in all directions parsol t REM 5 finest grid non SPINTO non restart parsol t Readers who are unfamiliar with DOS scripts i e batch files should note that only those lines which do not begin with REM an abbreviation for remark are acted upon THe execution of the script starts when spinto is entered at the DOS prompt REM The q1 is set up with the coarsest grid and it contains an incl spinxyz1 REM statement above its subsequent grid setting statements REM The spinxyz1 file is written by the spinto executable each time it runs REM but the spixyz1 files for runs 1 2 6 and 7 are written by the present REM script REM The spinto executable also writes a spinxyz2 file But this is not used REM Instead the present script puts all necessary additional instructions REM into the q2 file REM The present script also write the Q1spin file which gives SPINTO its REM instructions REM If it is desired to terminate execution of this script at any stage REM place the following goto end at the desired location if this file REM after first REMoving the REM from in front of it REM goto end REM The following environment variable SWEEPS is the number of sweeps REM to be carried out in all runs SET SWEEPS 5 REM When the following environment variable 0 Run 1 is omitted REM When it equals 1 Run 1 is carried out SET PARSOL 0 The environment variables are changed by editing the spinto bat file and it is possible to give SWEEPS a different value for each run if that is desired PARSOL must be set equal to 1 is facetted objects are to be handled by the PARSOL technique echo run started log GOTO PARSOL 1 REM Run1 to make pbcl dat REM initialization of file INCLuded in the q1 by the statement REM INCL SPINXYZ1 REM which must appear there immediately after the statement which REM sets the values of NX NY and NZ REM the 4s correspond to the fact that 2 levels of refinement are to REM be carried out with refinement factors of 2 in each case ECHO nx 4 nx ny 4 ny nz 4 nz spinxyz1 REM Perform the first finest grid run ECHO TEXT 1 no restart finest grid make pbcl Q2 echo lsweep 2 q2 echo run 1 starting log CALL SE copy pbcl dat pbcl sav echo pbcl saved log 0 REM Run 2 coarsest grid REM initialization of file INCLuded in the q1 ECHO no refinement spinxyz1 ECHO TEXT Run 2 no restart coarsest grid Q2 echo lsweep sweeps q2 echo parsol f q2 REM echo store prps q2 REM The following settings have no particular connection with SPINTO REM They over write those in the original Q1 relax u1 falsdt 1 0 q2 relax v1 falsdt 1 0 q2 relax w1 falsdt 1 0 q2 conwiz t echo run 2 starting log CALL SE echo run 2 completed log REM Prepare for SPINTO runs by echoing the necessary lines to

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  • ENC_D.HTM
    residuals of the pressure equation have the dimensions of mass per unit time rather than volume per unit time Since June 2011 DENPCO is set T automatically by EARTH whenever non uniform densities are present Density of first phase see RHO1 real Group 9 Density of first phase formulae for see RHO1 real Group 9 Density of second phase see RHO2 real Group 9 Density of second phase formulae for see RHO2 real Group 9 Density pressure correction see DENPCO logical Group 8 Density calculation of see RHO1 2 Group 9 Density indication of in phase 1 see DEN1 integer name Group 7 Density indication of in phase 2 see DEN2 integer name Group 7 DENST1 Integer used in GXDENS to denote first phase density DENST2 Integer used in GXDENS to denote second phase density Dependent variables default values of PHOENICS solves its differential equations by iterative guess and correct procedures Therefore its dependent variable arrays have to be filled with not unreasonable values at the start and this is handled automatically by the provision of default values usually 1 E 10 In a steady flow problem the initial guesses have no influence on the final solution Often therefore PHOENICS users pay no attention to the initial values being content to accept the default values Dependent variables setting PATCH wise sources of see COVAL command Group 13 PHOENICS describes a phenomenon involving the flow of momentum heat or material in terms of distributions in space and time of temperatures velocities pressures concentrations and other physically meaningful quantities These are the so called dependent variables The distributions involve ascribing numerical values to the temperatures velocities etc at each of an orderly array of locations called nodes or grid points and if the process is a time dependent one such distributions are calculated for each of a succession of instants of time PHOENICS can handle either one or two inter penetrating phases i e distinguishable fluids The flow of air alone is a single phase flow so is that of water alone When however a bubbly mixture of air and water is in question or that of air mixed with droplets of water the flow is said to be a two phase one and the air and water are called phases EARTH is equipped to solve for up to 150 dependent variables and as many more as you care to specify Certain of the dependent variables can be referred to by name These are Name Variable P1 the shared pressure of both the phases U1 the x direction velocity of the first phase U2 the x direction velocity of the second phase V1 the y direction velocity of the first phase V2 the y direction velocity of the second phase W1 the z direction velocity of the first phase W2 the z direction velocity of the second phase R1 the volume fraction of the first phase R2 the volume fraction of the second phase RS the volume fraction of the shadow of the second phase KE the turbulence kinetic energy of one of the phases the first phase by default EP the rate of dissipation of turbulence kinetic energy for the same phase H1 the specific enthalpy of the first phase H2 the specific enthalpy of the second phase C1 concentration variable for the first phase C2 concentration variable for the second phase C3 another concentration variable for the first phase C4 another concentration variable of the second phase and so on until C35 another concentration variable for the first phase However variables C1 to C35 need not be concentrations you can decide for yourself what they shall represent Depth Contour Menu Photon Help Cells are filled using the Warnock method each cell is subdivided until i a subdivision can be filled with one colour ii the size of the subdivision is smaller than the pixel size iii the cell has been subdivided a specified number of times This is the parameter DEPTH Suggested values of DEPTH range from 1 to 8 1 fills each cell with one polygon 8 fills each cell to pixel level Depth View Menu Photon Help The top view of the outline of the object is shown in the colour red and can be moved with the mouse relative to the centre of the screen which defines the position of the object relative to the view plane The red cross at the centre of the screen shows the current centre for rotating and spinning Desktop The area of the Commander from which the PHOENICS modules can be run by using a hotkey or icon DFEG Data Finite Element Generation directive see TR206 DIAGnostic Diagnostic messages are printed on occasion by the SATELLITE and by EARTH Those from the SATELLITE will normally be concerned with errors in PIL syntax and will indicate to the VDU except in batch mode output the PIL statement in error See group 25 and DEBUG to learn of what debug can be obtained from EARTH DIFCUT PIL real default 0 5 group 8 DIFCUT diffusion convection cutoff The diffusion contribution to the finite volume equation coefficient is diminished by DIFCUT ABS convection contribution but not allowed to become negative in order to account approximately for diffusion convection interactions Therefore the default value which cuts off diffusion when the cell Peclet number equals 2 0 corresponds to the hybrid interpolation scheme whereas DIFCUT 0 0 giving no diminution corresponds to the upwind interpolation scheme Diffuser object In the parlance of heating and ventilating engineers a diffuser as a fitting through which air enters a room To facilitate their introduction into simulation scenario special PHOENICS objects are provided Click here for the description in the FLAIR user guide Diffusion adjustments see GROUP 12 Diffusion fluxes accessing or altering see UDIFF logical Group 8 Diffusion neighbours accessing or altering see UDIFNE logical Group 8 Diffusion convection cutoff see DIFCUT real Group 8 DIGITISE Autoplot Help DIG ITISE The cursor can be used to obtain the x and y coordinates of any series of points on the screen These will be stored in memory as the next data set and can thus be plotted as normal The points can be saved on a disc file by using the ELEMENT SAVE command See also HELP on ELEMENT SAVE DIMENSion See the Encyclopaedia entry DIMENSIONING DIMENSIONING All the main PHOENICS arrays are dimensioned dynamically at runtime For more details see the entry Dynamic storage Direct access file A type of data file used by PHOENICS in which the information is accessed directly rather than sequentially see sequential formatted file Direct access files are quicker to access than sequential files but they are not portable across machines of different makes Direction Surface Menu Photon Help The surface contour will be generated by going through all the planes along the direction it can be X Y or Z DISPLAY When the word DISPLAY starts in the third column of a Q1 file all of the lines following it are displayed on the screen until the command ENDDIS also starting in the third column is encountered Library case 701 shows an example and illustrates the placing of the DISPLAY text between cls which clears the screen and pause which prevents further scrolling until RETURN is pressed Library case 492 shows that it is also possible to place pause statements within a DISPLAY section This is necessary if there are too many lines of text to be seen at any one time Valid PIL statements within a DISPLAY section if they start in the first or second column will be executed but not printed However it is recommended that they should not be placed there for the sake of orderliness When the VR Editor is being run the DISPLAY appears in the text window in the bottom right hand corner of the screen The display of the text window is controlled by the View Text box menu The pause macro will cause the text window to appear automatically if it had been turned off Additionally when the cham ini file contains the line display on the presence of DISPLAY in the Q1 file causes SATELLITE to copy the material in question into a file called display htm activate the default browser and display the contents of the file on the screen This is especially useful when the DISPLAY section contains HTML links as does for example that of library case h101 DISTIL PIL logical default F group 20 DISTIL when set T directs to logical unit 21 a distilled output This highly compressed print out is used when the code is installed in order to check that the test battery is working correctly For each variable stored it prints out an EXpected mean value and the calculated mean value and if these two numbers differ by more than a pre set tolerance a CHECK flag is printed See DSTTOL NULLPR and EX for further information Distilled output see DISTIL logical Group 20 DISWAL Command group 9 DISWAL DISWAL activates the calculation of the distance of the centre of each cell from the nearest wall and is equivalent to the following PIL commands SOLVE LTLS SOLUTN LTLS Y Y Y P P Y TERMS LTLS N N Y N Y Y STORE WDIS LITER LTLS 1000 The wall distance is used by the LVEL turbulence model and the IMMERSOL radiation model DIVIDE DIVIDE X DIVIDE Y Autoplot Help DI VIDE X or Y a i j Divide x or y coordinates of data elements i j by amount a Amount and element range will be prompted for At any stage forces return to OPTION See also HELP on MULTIPLY X MULTIPLY Y SHIFT X SHIFT Y DO LOOPS in PIL 1 DO loops are implemented in PIL by the commands DO DO loop counter low value high value increment pil statements ENDDO DO loop counter is a name to which the value of the DO loop counter is assigned Within the scope of a DO loop the DO loop counter can be accessed like any other Integer variable The DO loop counter must not have been defined previously as a PIL variable low value and high value define the range over which the DO loop counter runs they are Integer expressions increment is the optionally specified increment to the DO loop counter and is an integer expression which can be positive or negative If it is not specified it defaults to 1 ENDDO denotes the end of the DO loop For example for NX 2 NY 8 and NZ 12 the following DO loops are valid and execute 6 times DO II 1 6 DO II NY NX 1 DO II NX NY 2 NZ 2 2 ENDDO ENDDO ENDDO DO loops can be nested to a maximum depth of 20 The FORTRAN 77 convention for zero trip loops has been followed Thus for example DO II 2 1 ENDDO will not be executed at all 2 Examples of use a The following statements DO JJ 1 3 PATCH INL JJ NORTH 1 1 JJ JJ 1 1 1 1 ENDDO are equivalent to PATCH INL1 NORTH 1 1 1 1 1 1 1 1 PATCH INL2 NORTH 1 1 2 2 1 1 1 1 PATCH INL3 NORTH 1 1 3 3 1 1 1 1 b The following command sequence sets the inflow at the IY NY boundary of a POLAR case over the first section of the circumference and puts a fixed pressure over the remainder GROUP 13 Boundary conditions and special sources Inlet REAL UEXT UIN VIN ANGU ANGV INTEGER IM1 UEXT 1 0 DO II 1 IX1 ANGU XULAST XFRAC II UIN UEXT SIN ANGU IF II EQ 1 THEN ANGV 5 XFRAC II XULAST ELSE IM1 II 1 ANGV ANGU 5 XFRAC II XFRAC IM1 XULAST ENDIF VIN UEXT COS ANGV INLET IN II NORTH II II NY NY 1 1 1 1 VALUE IN II P1 VIN RHO1 VALUE IN II U1 UIN VALUE IN II V1 VIN ENDDO 3 See also the Encyclopaedia entry for CASE DMPSTK PIL logical default T The default setting ensures that on exit from the SATELLITE Q1 is overwritten by the contents of the stack and not COPYQ1 as was the case in PHOENICS V1 4 This means that any DO loop and other flow control constructs will be preserved When set to F Q1 will be overwritten with COPYQ1 which contains the processed PIL which results from the execution of the stack DO Advanced PIL command DO loops may be included in Q1 files The syntax is exemplified by DO II 1 NX 1 XC II 1 1 II 1 ENDDO Do All Menus Photon Help Do takes the current setting and draws the plotting element on the screen DO Photon Help DO var start value end value inc value PHOTON commands ENDDO The DO command enables a series of PHOTON commands to be repeated over a range of values The syntax is similar to a DO loop in FORTRAN however there is no label nor it is possible as yet to do nested DO loops It is available under both command mode and use files As in FORTRAN the increment value is optional For example to plot vectors over each of the Z planes DO IZ 1 M VEC Z IZ SH ENDDO When plotting contours it is necessary to provide additional values eg a sub division size with the fill option These must be supplied on the same record otherwise the DO loop will fail So that DO IX 1 M 5 CON TEM1 X IX FILL 0 01 ENDDO will provide colour fill contours but DO IX 1 M 5 CON TEM1 X IX FILL 0 01 ENDDO will cause an error However if the subdivision size is ommitted then the user will be prompted for it when the line is processed Dollar name patches If a PATCH name begins name where name is the four character name of a solved or stored variable a corresponding COVAL for variable PHI will introduce a source of PHI equal to VAL PHI CO NAME where CO is the third argument of the COVAL VAL is the fourth argument of the COVAL and NAME stands for the local value of the variable having the name which has been referred to DOMAIN Command group 6 DOMAIN is a 6 argument command used for the specification of sub domains for the purpose of generating a body fitted grid The 6 arguments are for integers Ifirst to Ilast Jfirst to Jlast and Kfirst to Klast in the corner coordinate nomenclature described under the BODY F entry Typically DOMAIN is used to define lines areas enclosed by 4 lines and volumes enclosed by 6 areas A DOMAIN command should always be followed by commands which fill in the grid coordinates within the sub domain defined For example the following commands will cause one edge of the domain to fall on a straight line the end points of which are the cartesian coordinates 1 0 1 0 1 0 and 10 0 10 0 10 0 SETPT 1 1 1 1 1 1 SETPT 1 1 NZ 1 10 10 10 DOMAIN 1 1 1 1 1 NZ 1 SETLIN XC XF XL XF LNK SETLIN YC YF YL YF LNK SETLIN ZC ZF ZL ZF LNK The SETPT commands set the cartesian coordinates of the end points of the line defined by DOMAIN and the SETLIN commands set the cartesian coordinates of the cell corners on this line to vary linearly with the K index from one end to the other Here LNK signifies linear in K ie it equals K KF KL KF See SETPT and SETLIN for further information DOMAIN Photon Help DO main prompts for the extent of the domain in Cartesian coordinates It is used when PHOTON is run without PHI or XYZ files attached in order to develop geometry files The default domain extent is 0 0 1 0 in X Y and Z DONACC the donor acceptor method DONACC is defaulted to F It is active only for transient two phase calculations that is for STEADY F and for ONEPHS F Under these circumstances DONACC T selects the so called donor acceptor scheme for formulating the volume fraction R1 and R2 equations The DONACC T setting is appropriate for calculations in which the two phases are separated by a distinct continuous interface as for example when the motion of a wave on a liquid surface or that of a large gas bubble in a body of liquid is to be considered The alternative two phase situation for which DONACC should remain F occurs when the two phases are finely dispersed at least as compared with the grid size examples are the steam water mixture and finely distributed fuel particles or droplets which are suspended in the gases within a furnace or combustion chamber The job of DONACC is to ensure the maintenance of the sharpness of the interface as it moves about in time Thus DONACC T involves special interpolation rules for determining the volume fraction used in the calculation of cell face mass fluxes For DONACC T RLOLIM sets the value of the phase 1 volume fraction ie R1 below which each cell is regarded as full of phase 2 fluid The value of R1 above which the cell is regarded as full of phase 1 fluid is RUPLIM A suitable value for RLOLIM is of the order of 0 001 to 0 01 Flows exhibiting a sharp interface may also be treated as single phase flows with discontinuities of properties See GALA and HOL Donor acceptor method see DONACC Dongle A hardware device which is used sometimes for locking PHOENICS to a machine DOS Disk Operating System Operating system used by PC s DOT Autoplot Help DO T n i j Plots data elements i j

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  • CHAM.INI Configuration File
    off zplanes off This sets the initial setting of the zplanes control in the graphical monitor The setting can be either on or off on means that in a 3D case the current Z plane number is displayed and updated during the calculation Time on This sets the initial setting of the Time indicator in the graphical monitor The setting can be either on or off on means that the current elapsed time and estimated time to completion are displayed and updated during the calculation Linewidth npixels This option sets the width of lines in pixels used for the graphical monitor The default value for npixels is 1 The larger the integer value the thicker the lines will appear on plots The image below shows three monitor plots with LineWidth 10 4 and 2 VRTOCFD Comments on Allows additional settings to be written to FACETDAT for early versions of MOFOR Multirun off The Editor will normally treat all lines after the STOP in Q1 as lines to be read just before writing EARDAT This allows settings made by the Editor to be overwritten or added to should the user so desire It also prevents the Editor from working in a multi run fashion Setting Multirun on will prevent the Editor from reading beyond the STOP of the current run Note that this can only be done for cases run in silent mode as interactively Editor will only see the first run of a multi run Similarly the Viewer can only see the first run of a multi run To run in silent mode open a command prompt by clicking on the CHAM icon labelled WINDF cd to the working directory if other than phoenics d priv1 then issue the command sil to run the Pre processor then runear to run the Solver NewCADconversion on When set to on Editor will use a set of readers from the OpenSceneGraph libraries to read files in the following formats and convert them to the PHOENICS VR geometry format STL Stereolithography file This is available in many popular CAD programs as an export format DXF Drawing Exchange Format File AutoCAD 3DS Autodesk 3ds Max WRL Virtual Reality Modelling Language file DW Files generated by DesignWorkshop from Artifice AC Files generated by AC3D from Invis IV Files generated by Open Inventor When set to off Editor will use the earlier on board converters for STL and DXF files The remaining data formats will be unreadable This should only be used as a fall back position should there be insurmountable problems with the OpenSceneGraph readers If the line is absent on is assumed Polargeom off When set to off Editor will write the cartesian coordinates of the facet corners to the FACETDAT file When set to on it will write the polar coordinates From 2012 Earth requires the cartesian coordinates so if the line is absent off is assumed Graphics In PHOENICS versions prior to 2009 this section was headed FTN386 This heading will still be

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  • Release Notes PHOENICS 2009: TR327
    reading Q1 a check is made to see if PATCH commands are attached to objects which have USER DEFINED or CELLTYPE types For all other object types an error message is displayed This situation can only arise when a user edits a Q1 by hand and makes an error in assigning PATCH commands to objects Phoenics December 2006 InForm gives error message if VOLU AREA or WHOLE flags are used for non VR patches When changing object type from USER DEFINED to any other dialog offers option to delete all user set patches for this object Cuboid objects which don t fit the grid e g because of large tolerance treated as faceted This allows Earth to scale any source correctly Phoenics October 2006 Allow hardware acceleration to be turned off from CHAM INI file full acceleration sometimes causes incomplete refresh of screen GROUP object allowed in middle of object list used to cause sequence error in locating objects in Solver Editor warns if ANGLED IN OUT object used with PARSOL F When using a volume object for an area type or vice versa allow dimension change from warning dialog Error in reading ASSEMBLY objects corrected Missing Endfacet lines added to optional STL output Allow more than 25 ARC lines in BFC mesh generator Allow more than 25 mouse points in BFC mesh generator Non integer object sizes and positions trapped for BFC and error message issued LSTEP no longer truncated to 9999 Improve poor behaviour when too many cells or time steps requested Setting now abandoned as soon as limit reached so error message is only displayed once Default geometries are not looked for unless an object of that type is read or created Correct sequencing error when cuboid object completely outside domain Get correct cell locations for cuboid object partially or wholly outside the domain Repair error which prevented friction patches being generated around a 198 blockage for BFC GCV When an InForm source is attached to a patch having the same name as an object 3 6 ignored the patch and attached the source to the object The source is now attached to the patch as it was in earlier versions Allow for comment lines longer than 68 characters in Q1 Prevent infinite loop when evaluation of variable in in OBJ line fails Improved accuracy of reporting line numbers of errors found in Q1 Speed of writing EARDAT for large cases improved File names can be 256 characters long Editor issues warning if INFORnBEGIN does not have matching INFORMnEND Number of times grid is matched during reading of Q1 reduced Radiating plate source corrected for cuboid object CCV collocated velocity solver removed as not used Corrected Errors and Improvements in Viewer Phoenics September 2009 Better error trapping for non existent files when changing time steps Phoenics August 2009 Better handling of contour scale range and variable name when moving between saved steps sweeps These could sometimes get lost Macro can advance by user set number of steps FILE n Near plane depth saved to macro file Better attribution of units to plotted variables Contour scale display can be switched to FPS or cgs units When domain is scaled vector heads retain original scaling Correction to display of polcu geometries used for moving objects in MOFOR or ROTOR Phoenics November 2008 Reduce number of time objects are redrawn Add macro ANIMATE FILE keyword to specify name of animation file to be written Phoenics September 2008 Make compatible with new PBCL DAT format whilst maintaining compatibility with previous format Allow saving of window image as JPG file FLAIR Calculate Beer Lambert visibility reduction as post processing option Allow View Centre to be set to position of minimum or maximum value from Probe Location dialog Phoenics August 2008 When Cancel is pressed on Macro dialog further attempts to run or save macros fail until Editor is shut and restarted Corrected Phoenics June 2008 Correction to surface contour Now strictly obeys contour averaging on off switch so raw unaveraged data can be saved to surface value and profile data files Surface contours redawn automatically when contour averaging switched on or off and when contour colour scale inverted Correction to contour plotting in cut cell when facet passes directly through bottom left and top right corners of cell If solid part was to right fluid and solid parts were plotted reversed Phoenics February 2008 Selection of multiple streamlines in streamline management dialog speeded up Added handling of PHOTON style PLINE elements Save image as jpg file Phoenics August 2007 Create line plot of any variable between two points Improve behaviour of F7 F8 keys when final solution selected from F6 Now goes to last step sweep previously went to first Scan RESULT for data pertaining to time step sweep being plotted for Show result Change object profile and surface file format to comma separated and file extension from prf srf to csv for easier input to Excel Adjustment of internal tolerance when contour plotting in cylindrical polar coordinates with PARSOL Allow free choice of variables for generating vectors Add dialog to control lighting of scene Error message displayed if no data found in RESULT for time history Viewer could hang Reorganise Contour Vector Surface Options dialogs Phoenics April 2007 Allow choice of Total X Y X Z or Y Z components for vectors Allow for user set colour palette Corrections to contour plotting for PARSOL in cylindrical polar coordinates when cut cell lies in ve Y quadrants Allow vector plotting to omit one velocity component to display secondary flow Allow animation of phase 2 vectors Phoenics December 2006 Viewer allows vectors to be plotted in a single colour Viewer allows EPOT variable to be plotted inside participating solids Viewer reads cut cell data file PBCL DAT using fixed format allowing for larger number of cut cells Viewer does not use OBID to blank cells if MOFOR is not active Under some circumstances F8 in Viewer advanced to the last step instead of

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