CHAM Seminar PHOENICS 2009 September Computer Simulation of Fluid Flow, Heat Flow, Chemical Reactions and Stress in Solids.

CHAM Seminar Contents This presentation shows some of the new features in PHOENICS 2009 The talk is in five parts: –Pre-processor (VR-Editor) –Post-processor (VR-Viewer) –Solver (Earth) –General improvements (common to all modules) –Highlights of earlier improvements

CHAM Seminar VR Editor Improvements The WIND Object has been extended to add the ground plane as well as the flow and pressure boundaries. VR Editor Improvements This ensures that the surface roughness and surface friction settings are consistent with the inlet profile.

CHAM Seminar VR Editor Improvements Ambient pressure and ambient temperature settings. VR Editor Improvements

CHAM Seminar VR Editor Improvements The ambient settings represent the pressure and temperature outside the domain. They can be used as the initial value, and are the default values at all inlets and openings. The reference density used for buoyancy is also derived from the ambient values. This should ensure that the buoyancy settings are always self consistent. It also makes it easy to change the external temperature at all openings or inlets. VR Editor Improvements

CHAM Seminar VR Editor Improvements This image shows what can happen if the reference density for buoyancy is not right. VR Editor Improvements

CHAM Seminar VR Editor Improvements When the reference density for buoyancy is right. VR Editor Improvements

CHAM Seminar VR Editor Improvements InForm commands can be linked directly to objects, and the dialogs for adding InForm to objects have been improved. The dialog allows such commands to be created with the LOCATION keyword being taken as the name of the current object. InForm commands created in this way are held in the Q1 together with the remaining object attributes. – > OBJ, TYPE, INLET > OBJ, INFSRC_P1, den1*14*yg with area > OBJ, INFSRC_W1, 14*yg with onlyms VR Editor Improvements

CHAM Seminar VR Editor Improvements As an example, the image below shows the settings required to make the inflow mass source and velocity at an INLET a linear function of the height. VR Editor Improvements If the object is copied or arrayed, the InForm commands will also be copied. The ‘classic’ style (source of... would require manual copying.

CHAM Seminar VR Editor Improvements To produce this flow field VR Editor Improvements

CHAM Seminar VR Editor Improvements Patches attached to USER-DEFINED object are now listed by name as part of the object attributes in the Q1 file. – > OBJ, TYPE, USER_DEFINED > OBJ, PATCHES, patch1, patch2, patch3, patch4, patch5 > OBJ, PATCHES, patch6,... patchn The ‘PATCHES’ attribute contains a list of the patch names associated with this object. As many PATCHES lines as needed to hold all the patch names can be used. This makes hand-editing the Q1 much safer, as the patch-object link no longer depends on the object numbers which change when cutting and pasting the object list.

CHAM Seminar VR Editor Improvements The number of sweeps per time step can be set from the Editor Main Menu Numerics panel (has always been possible with InForm). In many transient cases more sweeps are required for the first few steps, and possibly later on when a boundary condition changes - a jetfan switches on or off for example. This provides a convenient way of pre-setting the number of sweeps to be performed on each time step. The number of sweeps can also be changed interactively at run-time.

CHAM Seminar VR Editor / Viewer Improvements Clipping plane objects have been introduced. In the past, it has been awkward to see inside objects. Here the airspace in the car park is subtracted from a solid domain. To see inside, the airspace had to be hidden.

CHAM Seminar VR Editor / Viewer Improvements Clipping plane objects have been introduced. In the past, it has been awkward to see inside objects. The clipping planes remove unwanted parts showing the inside clearly.

CHAM Seminar VR Editor / Viewer Improvements Clipping plane objects have been introduced. In the past, it has been awkward to see inside objects. Clipping can be turned off for vectors and contours.

CHAM Seminar VR Editor / Viewer Improvements Clipping plane objects have been introduced. In the past, it has been awkward to see inside objects. Clipping can be turned off for vectors and contours.

CHAM Seminar VR Editor / Viewer Improvements The font size can be changed in Editor/Viewer. If a dialog is too tall to display on screen, reducing the font size will make it fit. Better attribution of units to plotted variables in Viewer. Where possible, the Viewer will display the units of the plotted variable. The Viewer display can be switched to FPS or cgs units instead of the default SI units. When the domain is scaled, vector heads retain their original scaling. Domain scaling is useful for long thin domains such as tunnels. Not scaling the vector heads improves the appearance of the plot.

CHAM Seminar Earth Improvements Often there is a need to link the flow rate and temperature at one boundary condition to the flow and temperature at another. Typical examples are –Ducting that is not explicitly modelled that joins one part of the domain to another –The intake and exhaust from an Induction Fan –Active chilled beams This can now be achieved by a pair of linked ANGLED-IN objects.

CHAM Seminar Earth Improvements One ANGLED-IN, set to extract flow, acts as a ‘donor’. The immediately-preceeding or immediately-following ANGLED-IN takes the flow rate from the ‘donor' and uses it as the inflow: –The temperature, smoke and other scalars are taken as the mass-averaged average values at the ‘donor' object. –The density is evaluated at the average temperature and ambient pressure. –The velocity is deduced from the mass flow rate (taken from the ‘donor’), the flow area and the deduced density. –The turbulence values are computed from the turbulence intensity, velocity and hydraulic diameter. The linking happens in pairs, so that a linked pair can be copied or arrayed. The correct objects will stay linked.

CHAM Seminar Earth Improvements Here a pair of linked ANGLED-Ins are used to represent a duct joining the left and right-hand sides of the domain.

CHAM Seminar Earth Improvements Here a pair of linked ANGLED-Ins are used to represent a duct joining the left and right-hand sides of the domain.

CHAM Seminar Earth Improvements Here a pair of linked ANGLED-Ins are used to represent an induction fan.

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements From 2008 the RESULT file ‘Nett source' echo showed the average value of scalars at mass boundaries. This worked well for inlets, but at outflow boundaries produced unreliable values unless the flow was entirely out (or in). In many cases the fixed pressure boundaries are partially inflow and partially outflow so this was not a satisfactory state. We now calculate and print the inflow and outflow components at pressure boundaries, and deduce the average scalar values for each.

CHAM Seminar Earth Improvements The induction fan example shown earlier has this in RESULT: The mass source is reported as: – Nett source of R1 at patch named: OB2 (B3 ) = E+00 – Nett source of R1 at patch named: OB3 (B4 ) = E+00 – Nett source of R1 at patch named: OB4 (B5 ) = E+00 (Mass Out E+00 In E+00) – Nett source of R1 at patch named: OB5 (B6 ) = E+00 (Mass Out E+01 In E+00) – Nett source of R1 at patch named: FIR1 (B8 ) = E-01 – pos. sum= neg. sum= – nett sum= E-05 B3 and B4 are the linked ANGLED-INs, so the mass sources are equal and opposite. B5 and B6 are pressure boundaries, and the in/out split can be seen.

CHAM Seminar Earth Improvements The TEM1 source is reported as: – Nett source of TEM1 at patch named: OB2 (B3 ) = E+05 (Average E+01) – Nett source of TEM1 at patch named: OB3 (B4 ) = E+05 (Average E+01) – Nett source of TEM1 at patch named: OB4 (B5 ) = E+06 (Ave Out E+02 In E+01) – Nett source of TEM1 at patch named: OB5 (B6 ) = E+06 (Ave Out E+01 In E+01) – Nett source of TEM1 at patch named: FIR1 (B8 ) = E+04 (Average E+01) – Nett source of TEM1 at patch named: FIR1A (B8 ) = E+05 – pos. sum= E+06 neg. sum= E+06 – nett sum= E+05 At B3 and B4 the average temperature is the same. At B5 and B6 the average temperature of the outgoing air is seen. Incoming air is at ambient.

CHAM Seminar Earth Improvements In transient cases, the time-variation part of the mass error is printed. – Transient contribution to R1 nett source = E+00 (Mass Out E+01 In E+01) – Nett source of R1 at patch named: OB1 (B1 ) = E+00 – pos. sum= neg. sum= – nett sum= E-03 From this one can see that there is an overall mass balance. It will make judging convergence of transient cases easier.

CHAM Seminar Earth Improvements Users have been requesting multiple monitor points for assessing convergence. There are also many cases where it is of interest to monitor the time-variation of a quantity. The TIME-HISTORY object partially fulfils these needs, but not in all cases. It is now possible to use InForm to create a table of any variables as a function of sweep or time. Each table is written to a separate file, there can be as many tables as needed, and each table can contain any number of columns.

CHAM Seminar Earth Improvements The format of the InForm table-making command is very simple. It is: (TABLE in file_name is GET(var1,var2,...,varn) with HEAD(col1,col2,...,col3)!sweep) where –File_name is the name of the file to write –var1,var2,...,varn are the variables to write. These can be any valid InForm expression. –col1,col2,...,coln are headings to use in the table. –!sweep states that the table is to be added to at the end of each sweep. For a transient table, the line would end !time. The file is written in Comma-Separated-Variable format, so if it is given a.csv extension, it will read straight into Excel.

CHAM Seminar Earth Improvements For example, adding the lines SAVE19BEGIN (TABLE in MONPLT1.CSV is GET(P1[1,3,3],P1[NX,3,3],P1[1,3,NZ-5]) WITH HEAD(P1_1,P1_2,P1_3)!SWEEP) (TABLE in MONPLT2.CSV is GET(W1[1,3,3],W1[NX,3,3],W1[1,3,NZ-5]) WITH HEAD(W1_1,W1_2,W1_3)!SWEEP) SAVE19END to a library case will produce two additional files called MONPLT1.CSV and MONPLT2.CSV.

CHAM Seminar Earth Improvements The first few lines of MONPLT1.CSV are: ISWEEP, P1_1, P1_2, P1_3 1, E+00, E+00, E+00 2, E+01, E+01, E+01 3, E+01, E+01, E+00 4, E+01, E+01, E+01 5, E+01, E+01, E+01 6, E+01, E+01, E+01 7, E+02, E+01, E+01 8, E+02, E+02, E+02 9, E+02, E+02, E+02 10, E+02, E+02, E+02 11, E+02, E+02, E+02 This can then be brought into Excel to create a scatter plot

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements As any valid InForm formula can be tabulated, the method can be used to track –average values, –min/max values –Sums –Anything!

CHAM Seminar Earth Improvements PHIDA=T is now the default. This makes the saved files smaller, and also quicker to read and write. The format of the PBCL.DAT file has been changed to make the writing process more efficient. When PHIDA=T in PREFIX, PBCL.DAT is also unformatted. Old-style PBCL.DAT files are still accepted by Earth and Viewer. If the main F-array size is increased at the start of a run, the increased size is written to a local CHAM.INI file to remove the need for expansion on the next run.

CHAM Seminar Earth Improvements The Earth solver can now output files in VTK format. These files are compatible with the ParaView post- processor available for free download on the web.

CHAM Seminar Previous highlights Here follow some improvements made in the previous release which are worth mentioning again, in case they have been missed. PHENICS Today

CHAM Seminar VR Editor Improvements The Flair DIFFUSER objects can be freely rotated about any axis. If they are rotated out of the plane of the grid, they must lie on the face of a blockage, as they use the ANGLED_IN code for implementation. The cells adjacent to the diffuser must be not more than half the diffuser depth in that direction, else the boundary condition will not be picked up.

CHAM Seminar VR Editor Improvements For all OUTLET, OPENING or ANGLED_OUT objects, a quadratic loss coefficient K can be specified. The loss coefficient represents the loss of dynamic head through the exit. ∆P = 0.5KρVel 2

CHAM Seminar VR Viewer Improvements Visibility reduction can be estimated from the Beer-Lambert law The intensity reduction ratio LR in % is computed from: LR = 100.*Iz/I0 = 100.*exp ( -  C s *  *K m *dz ) where K m =smoke extinction coefficient (7600 m^2/kg),  =fluid mixture density (kg/m^3),  C s =particle smoke concentration (kg/kg),

CHAM Seminar VR Viewer Improvements If reduction is greater than 0.015%, the looked- at location is not visible

CHAM Seminar VR Viewer Improvements The View Centre can be jumped to the probe, Minimum location or maximum location.

CHAM Seminar VR Viewer Improvements The View Centre can be jumped to the probe, Minimum location or maximum location. The probe can be jumped to the Minimum location or maximum location. The Viewer dialog shows the minimum and maximum values and their locations.

CHAM Seminar VR Viewer Improvements The View Centre can be jumped to the probe, Minimum location or maximum location. The probe can be jumped to the Minimum location or maximum location. This is an easy way to find where the biggest and smallest values are.

CHAM Seminar Earth Improvements Simple thin-plate treatment introduced. BLOCKAGE objects made from material 299 have following properties: –Cells with cut faces are blocked to flow –Open cells are filled with domain material This allows many shapes to be represented well enough for practical purposes.

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements

CHAM Seminar Earth Improvements Update monitor to allow: o Change of LSWEEP

CHAM Seminar Earth Improvements Update monitor to allow change of: o Change of LSWEEP o Change of CONWIZ maximum increment o Change between linear and false-timestep relaxation

CHAM Seminar Earth Improvements Update monitor to allow change of: o Change of LSWEEP o Change of CONWIZ maximum increment o Change between linear and false-timestep relaxation o Change of monitor mode

CHAM Seminar Single STL object repaired by FacetFix General Improvements Can give detection problems if too many inter- penetrating volumes in one object

CHAM Seminar General Improvements Divided into individual objects Will be detected correctly Import by Group can also read DAT files

CHAM Seminar