Web directory, archive
Search web-archive-uk.com:

Find domain in archive system:
web-archive-uk.com » UK » C » CHAM.CO.UK

Total: 682

Choose link from "Titles, links and description words view":

Or switch to "Titles and links view".
  • PHOENICS Newsletter Archive

    Original URL path: http://www.cham.co.uk/newsletter_archive.php (2016-02-15)
    Open archived version from archive

  • Terms for Performance of Consultancy Work
    best available scientific techniques the execution of all consultancy contracts are undertaken on a best efforts basis CHAM uses best practices in the creation and application of the CFD models it employs based upon data supplied and reasonable assumptions agreed with the client Whilst the results generated are reasonable in both qualitative and quantitative terms they cannot be relied upon in their entirety in isolation from physical testing practices which may highlight variance in or omission of boundary and other operational conditions from those specified within the CFD model Limitation of liability The total liability of CHAM associated with consultancy work whether consequential or otherwise will be limited to the total amount received by CHAM during the course of the contract or a twelve calendar month period whichever is the less It is the responsibility of the Client to ensure that all information provided to CHAM is accurate and is supplied before the starting date of the project CHAM will do all in its power to accommodate late alterations but reserves the right to pass on to the Client any costs incurred due to such changes or to any delay in the supply of data CHAM reserves the right to

    Original URL path: http://www.cham.co.uk/consultancy_TandC.php (2016-02-15)
    Open archived version from archive

  • PHOENICS/ FLAIR - Introductory Training Course
    library cases Running Modules PHOENICS VR Editor Handset functions Main menu functions Object types and dialogs PHOENICS VR Viewer Handset functions Saving animations Workshop 14 00 16 30 Creation of user geometries Shapemaker AC3D Importing geometries from CAD Importing STL files Importing DXF files Repairing defective geometries Workshop Close Day 2 09 30 13 00 Theory Mathematical basis of PHOENICS Solution techniques Convergence control Meshing Setting grids Interaction with PARSOL

    Original URL path: http://www.cham.co.uk/introcourse.php (2016-02-15)
    Open archived version from archive

  • PHOENICS Fire-related Case Studies and Demonstration Examples
    temperatures In addition it can predict effects of smoke movement or any other gaseous pollutant helping to achieve safe design of buildings underground systems aircraft or train cabins etc FLAIR can also be used by various regulatory bodies and safety consultants The following provide links to a variety of supportive material The role of PHOENICS FLAIR CFD software for improving the capabilities of Fire Brigades in the analysis and prognosis of fire and chemical release hazards CHAM UK PDF document 392kb Further images from FLAIR case studies PDF document 812kb PHOENICS FLAIR Product Description CHAM UK PDF document 834kb CHAM Case Study Airport Fire Test Example PDF document 643kb PHOENICS FLAIR 3 6 1 presentation PHOENICS User Meeting Eindhoven May 2005 CHAM UK Powerpoint presentation 1 41mb Fire Smoke Simulation in a Multi Storey Underground Car Park PDF document 154kb Fire in an Underground Railway Station PDF document 305kb Fire in an Underground Car Park RUCON The Netherlands Wembley Stadium fire study PDF document 118kb CFD Applications of PHOENICS on Building Environment and Fire Safety Design Ove Arup Australia Powerpoint presentation 1 70mb PHOENICS in Safety Analysis of Offshore and Underground Constructions FlowConsult Norway Powerpoint presentation 3 66mb Validation of PHOENICS 3 5 for modelling Tunnel Ventilation Systems under Fire Conditions Stephen Grubits Assoc Australia PDF document 223kb Car Park Fire CHAM UK PDF document 535kb Fire in a Room PHOENICS 3 5 Demonstration Study NIST USA Underground Garage Ventilation and Fire Study Van Hooft The Netherlands Multi storey Car Park Fire Study Van Hooft The Netherlands Madrid Xanadu Shopping Mall Fire Study CHAM UK Memorial Tunnel Fire Ventilation System ENEA Italy Fire in a Building PHOENICS 3 1 Demonstration Case CHAM UK Train Fire in a Tunnel Effect of Tunnel Ventilation Flowsolve UK A Fire Safety Study Rome Metro

    Original URL path: http://www.cham.co.uk/casestudies/fireapps.php (2016-02-15)
    Open archived version from archive

  • PHOENICS Building-related Case Studies & Demonstration Examples
    Swimming Pool complex PDF document 290kb CHAM Case Study Natural Convection in a Nuclear Waste Storage Warehouse PDF document 383kb PHOENICS validation for German Industry Standard DIN 1005 4 Zimmermann Becker GbmH Powerpoint presentation 2 79mb English translation Powerpoint presentation 2 58mb CHAM Case Study Urban Wind Flows AVA study PDF document 2 38mb CHAM Case Study Urban Wind Flows Building geometry created using AC3D PDF document 265kb PHOENICS FLAIR 3 6 1 presentation PHOENICS User Meeting Eindhoven May 2005 CHAM UK Powerpoint presentation 1 41mb New ways of Modelling with Phoenics M W Zander Germany PDF document 7 65mb Ventilation of an Opera House ShenZhen Architecture Research Institute China PDF document 195kb Internal flow within a multi storey building CHAM UK PDF document 332kb Applying CFD to Environmental Flows Connell Wagner Australia Word document 2 33mb Methodology for the Evaluation of Natural Ventilation in Buildings Using a Reduced Scale Air Model Massachusetts Institute of Technology USA PDF document 2 20mb Advances in combined Building Thermal Simulation and Prediction of Air Flows with PHOENICS Peutz The Netherlands Powerpoint presentation 11 6mb Development of End User Computing System for the design of HVAC Tokyo Gas Japan Powerpoint presentation 667kb Ventilation System design for a Roadway Tunnel in Acapulco Mexico Vortex de Mexico Mexico Powerpoint presentation 9 12mb Modelling the performance of WECS installed into Residential Towers American University of Cairo Egypt Powerpoint presentation 476kb CFD Simulation of Turbulent Flows and Pollutant Dispersion around Groups of Buildings VIPAC Australia Powerpoint presentation 2 89mb The Risk Assessment of an Ammonia Intoxication caused by the Wreck of a Plant in Town Conditions Moscow State Institute of Steel Alloys Russia Demonstration Case Ventilation of a Bus Terminal Interchange CHAM UK Wind effects around a Bus Canopy Flowsolve UK Passive slab Pre cooling of a new

    Original URL path: http://www.cham.co.uk/casestudies/hvacapps.php (2016-02-15)
    Open archived version from archive

  • Additional Presentations
    Natural convection in a warehouse Natural convection in a nuclear reactor Transient simulation in a vapour turbine Overview of Twenty Case Studies Powerpoint presentation 21 4mb Convection with rotational motion Rotating paddles in a tank Sliding grid case Mixing flow in a chamber Air plane Flat frame burner Metal melting furnace Mixing chamber Oil droplet in a pipe Natural convection in a crucible furnace Fire an a tunnel Boil over

    Original URL path: http://www.cham.co.uk/casestudies/additionalcases.php (2016-02-15)
    Open archived version from archive

  • CONWIZ : The 'Convergence-Promoting Wizard' for PHOENICS
    convergence is more probable for CONWIZ makes conservative rather than optimal choices Obviously however this play safe policy has led to no serious ill consequence in the present case The next two monitor plots show what happens when the van velocity is multiplied by 100 0 As before and for all pairs of pictures below the standard settings are above and those of conwiz below conw 100 Evidently the standard settings which procured convergence for the original case were not able to do the same for the increased velocity CONWIZ by contrast was able to cope with the changed input data quite well Library case 492 the gas turbine combustor A somewhat tougher test of the capabilities of CONWIZ is provide by this case also a veteran by reason of its more numerous active physical processes including turbulence and chemical reaction Once again the effects of the standard and CONWIZ settings are compared by way of the graphical monitor plots which may be displayed by clicking below This time the slower convergence of CONWIZ is more noticeable However it is gratifying to observe that convergence gas been achieved with CONWIZ T as the only setting which the user has had to make It should also be remarked that although the maximum absolute corrections appear to fluctuate more wildly for CONWIZ their actual values are extremely small Library case w802 the nuclear steam generator CONWIZ has not yet been taught anything specific about two phase flow it is therefore interesting to see what happens when it is presented with another classic case This is the nuclear steam generator which was the application which long ago led to both to the invention of the IPSA algorithm and to the creation of PHOENICS itself CONWIZ is being asked to tackle this problem without even being given a hint by way of FIINIT STEAM about the expected volume fractions of steam and water in the generator The next two pictures show the relevant monitor plots Not bad for a beginner one might conclude although the levelling off of some residuals requires examining Since the selection of relaxation parameters for two phase flow is notoriously difficult this first time success of CONWIZ is especially encouraging Library case b524 the Mizuki impeller CONWIZ has been kept in equal ignorance of the specific features of body fitted coordinate calculations which it therefore treats in the same way as those with cartesian or polar coordinates The results for the veteran Mizuki impeller problem are shown in the next two graphical monitor plots Convergence is good for both the standard and the CONWIZ settings but the episode at the end of the CONWIZ run raises the question why However this question is as much about the credibility of the residual plots as it is about the success of CONWIZ Also interesting is what happens when the rotation speed is increased tenfold This is shown by the next pair of plots Evidently CONWIZ handles the change without difficulty but the standard settings no longer procure convergence Library case i205 temperatures in a computer room Convergence is particularly difficult to procure for flows with natural convection for sometimes differing false time steps may be required for the vertical direction velocity the horizontal velocities the temperature If CONWIZ can handle them well users of FLAIR the HVAC version of PHOENICS will be much relieved The next two pictures provide some encouraging evidence in respect of library case i205 It appears that CONWIZ performs quite as well as the standard settings 5 How does CONWIZ work The main features of CONWIZ are as follows It starts by making guesses about reference values of length velocity density and temperature From these it deduces and sets some initial values of variables including the DVELDPs i e the rates of change of velocity with pressure difference at every point It sets linear under relaxation factors for all variables including the DVELDPs It sets maximum values to the increments per sweep for some variables In some circumstances it can improve its settings in the course of the computation 6 How reliable is CONWIZ Does CONWIZ always work No However as the above examples have shown it often does pretty well When CONWIZ has failed to procure complete convergence it has sometimes transpired that there is some special instability promoter in the way in which the problem has been set up Fires represented as fixed heat sources regardless of flow conditions have led to solutions which not even CONWIZ can persuade to settle down CONWIZ has been in existence only since February 2004 and has not been receiving full time attention too much should therefore not yet be claimed for it Nevertheless to set CONWIZ T is certainly a wise thing to do at the start of a new calculation 7 How can users participate in the promotion of convergence Although CONWIZ is ready to tackle any problem on its own it will respect user s settings and accept their assistance If users prefer to use false time step relaxation for any variable other than velocity CONWIZ will print a message questioning their wisdom but it will not change the settings It will however insist on using linear relaxation for velocities Any user set linear relaxation factor will be used in preference to its own User set VARMINs and VARMAXs will also be respected even if being too narrowly defined they distort the final solution 8 How can CONWIZ be further developed There is much scope for CONWIZ to improve its performance for example as follows By systematically inspecting all geometry affecting settings and all boundary and physically significant initial conditions so as to make better estimates of reference lengths velocities and densities By increasing horizontal direction vertical velocity coefficients in regions where un balanced horizontal gradients of gravity are likely to provoke large vertical velocity corrections By detecting regions in which corrections exhibit periodicity and applying appropriate damping By examining the special features of body fitted coordinates

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_lecs/conwiz/conwiz.htm (2016-02-15)
    Open archived version from archive

  • fluisol.htm
    PHOENICS PHOENICS 3 6 has three ways to compute the forces and moments on a body namely To place an imbalance patch around the object in question with appropriate COVAL specifying only which velocity and therefore direction is in question this gives print out of both forces and moments To set PARSOL T and thereby automatically activate print out of pressure and friction forces on facetted objects To set NAMGRD F1 and thereby print out of pressure forces calculated as though for a formula 1 racing car The three methods ought to agree but at the present moment they do not always do so as illustrated by the following extract from data relating to case 805 flow past a sphere next Method 1 three differently sized imbalance patches Forces on patch IMBL3 2 Z wise force 2 508054E 00 Forces on patch IMBL4 3 Z wise force 2 503020E 00 Forces on patch IMBL5 4 Z wise force 2 495262E 00 Forces on patch IMBL810 Z wise force 2 872604E 00 Forces on patch IMBL815 Z wise force 2 300270E 00 Method 2 Integrated force on object B3 Total in Z 3 097499E 00 Pressure 3 097499E 00 Friction 0 000000E 00 The differences between the imbalance and integrated force calculations are rather great The reason for them is being sought the coarseness of the grid being the prime suspect next Summary of PHOENICS capabilities It appears wise to conclude that although PHOENICS does now have easy to activate means of calculating forces exerted by fluids on immersed bodies more research is required into their satisfactoriness for aerodynamic purposes On the other hand if the question is Will x kg of dynamite exploded at point A break the windows in building B at a distance y PHOENICS will certainly be able to give an answer of accuracy commensurate with that with which window strength is known In the modern world security authorities and insurance companies would be wise to turn engage CFD savvy consultants for advice before the bomb goes off next back or contents 4 Fluids induce mechanical and thermal stresses on solids at rest SFTA Solid Fluid Thermal Analysis To know the total force on a body is often not enough the distribution of stress i e force per unit area within the body may be of even more interest and these may be caused by temperature gradients as well as by pressure and friction PHOENICS has long possessed its unique means of computing the internal stresses whether thermally or mechanically induced This method has relied on the supposition that the velocity with which the solid moves is negligible so that the storage space allocated to the velocity components can be used for the displacements instead It has exploited also the fact that the equations governing the displacements are so similar in form to the momentum equations that PHOENICS can solve for both simultaneously Click here for an early demonstration next Three shortcomings and their remedy As originally implemented the method failed to take into account the effects of bending moments convergence was slow and extreme care had to be taken with the coding so as to ensure that velocities and displacements were properly distinguished from one another at all cell faces Recently a new algorithm has been devised which converges rapidly because the u v and w equations are no longer linked by the equivalent of pressure includes the bending moment terms click here for an example and since it no longer depends on calculating the dilatation from a modified pressure correction equation no longer requires the velocities and displacements to be stored contiguously The last point is fortunate because as will be argued below the need can already be foreseen for being able to calculate both velocities and displacements for the same locations next Work in progress Some of the interesting features of SFTA can be explained by reference to the Q1 file of a current project and by inspecting a PHOTON vector plot vectors at ix 1 and 23 The run giving rise to the latter plot was one in which the only influence was the internal pressure of the hydrogen gas and the question was do the solutions for displacements in the metal conform to expectations The answer is not quite for the vectors for ix 1 are not identical with those for ix 23 and the axial direction vectors are inexplicably small near the axis Why Incomplete convergence Inaccurate display Incorrect setting of boundary conditions Imperfections in the internal coding The answer will be found after the proper study This is work in progress next Probably the main reaction after inspection of the Q1 file is How different is the world of the PHOENICS developer from that of the PHOENICS user The later uses the VR Editor and VR Viewer but the developer can not because he is working in territory that the GUI knows nothing about Fortunately he does have the facilities of PIL at his disposal but he activates them by hand editing of the Q1 In due course it will become possible to set up SFTA problems via the GUI and to display displacements separately from velocities but only after the developer has finished his work Today one can cross Australia from South to North in a comfortable train but only because the pioneers of 150 years ago made the same journey by foot next back or contents 5 Fixed shape solids in prescribed motion influence fluid flow Applications Practically important phenomena pertaining to the above heading are very numerous They include fans blow air piston cylinder crankshaft mechanisms compress it inter meshing helix and other positive displacement machines do the same the Space Shuttle leaves is launching pad a ski jumper takes off a rotating paddle stirs liquid in a chemical reactor liquid in a half filled tank sloshes as a consequence of tank motion and many more Current capabilities The PHOENICS moving frame of reference technique i e

    Original URL path: http://www.cham.co.uk/phoenics/d_polis/d_lecs/fluisol/fluisol.htm (2016-02-15)
    Open archived version from archive


web-archive-uk.com, 2017-12-19