PAT312, Section 61, December 2006 S61-1 Copyright 2007 MSC.Software Corporation SECTION 61 VIEWFACTOR RESULTS AND FILES

PAT312, Section 61, December 2006 S61-2 Copyright 2007 MSC.Software Corporation

PAT312, Section 61, December 2006 S61-3 Copyright 2007 MSC.Software Corporation VIEWFACTOR FILES l Use default filenames for use with Patran Thermal l Input files l vfin.dat (text) l Enclosure definitions l vf.ctl (text) l Viewfactor run control parameters l template.dat.apnd (text) l VFAC templates

PAT312, Section 61, December 2006 S61-4 Copyright 2007 MSC.Software Corporation l Intermediate files l vf.msg (text) l Viewfactor run status l vf.diag (text) l Viewfactor sums l vfraw.dat (binary) l Raw data for viewfactors and resistors l vfrestart.dat (scratch) l vfrestart.stat (scratch) l Output files l vfnode.dat (text) l Radiosity node definitions l vfres.dat (binary) l Radiation resistors VIEWFACTOR FILES (Cont.)

PAT312, Section 61, December 2006 S61-5 Copyright 2007 MSC.Software Corporation VIEWFACTOR FILE SIZES l Upper bound estimate on the size of resources required for a viewfactor run l Any enclosure containing more than 1,000 surfaces will begin to tax system resources l System demand is not a function of MSC.Patran efficiency but of the nature of computing viewfactors themselves l Viewfactor computation uses /tmp as a repository of scratch files l Write to /tmp is hard-wired and not affected by environment variable TMP l Total demand on /tmp and local disk space are essentially the same except that when viewfactor computation is complete the /tmp space is released

PAT312, Section 61, December 2006 S61-6 Copyright 2007 MSC.Software Corporation VIEWFACTOR FILE SIZES (Cont.) l Disk storage (both in /tmp and local) required is l The sum of the space required for vfres.dat and vfraw.dat l Space required for vfres.dat l The sum over all enclosures of (# of element surfaces in enclosure i * 4)**2.0 * 45 bytes l Space required for vfraw.dat l The sum over all enclosures of (# of element surfaces in enclosure i * 4)**2.0 * 68 words * # of bytes per word l # of bytes per word is typically 4 but sometimes 8. l This is an upper bound since the multiplier 4 on the "# of element surfaces in enclosure i" assumes a nonexistant or noneffective collapse flag. Using the collapse flag will reduce this factor to somewhere between 1 and 4. Smaller files are not summed in the resource demand since computation is an upper bound on the files which clearly dominate the demand. l The amount of memory required (usually virtual, i.e, swap) is given in Appendix C of the MSC.Thermal Viewfactor Manual (available online in the Document Library)

PAT312, Section 61, December 2006 S61-7 Copyright 2007 MSC.Software Corporation * Sample VFCONTROL file. * * Pathname $PATH: * Message file name $MESSAGE_FILE: vf.msg * Diagnostic data file name $DIAGNOSTIC_FILE: vf.diag * Title $TITLE: 'INTERIOR OF HEATED CYLINDER RADIATING TO SPACE.' * Input data file name $IN_DATA: vfin.dat * Template file name $TEMPLATE_FILE: template.dat * Raw view factor data file name $RAW_DATA: vfraw.dat * Radiation resistor file name $OUT_DATA: vfres.dat * Radiosity node file name $RAD_NODE_FILE: vfnode.dat * $STATUS_FILE: vfrestart.stat * $RESTART_FILE: vfrestart.dat * 0 = full run, 1 = view factors only, 2 = resistors only $RUN_CONTROL: 0 * $RESTART_FLAG: 0 * $CONVERGE: -1.0 $ZERO: 0.0 $APPROX_CURVE: 0.1 * Contour Double_area Weighting $GAUSS_ORDER: * minimum maximum $AXISYM_SURFACE: 5 13 $EOF: SAMPLE VFCONTROL FILE

PAT312, Section 61, December 2006 S61-8 Copyright 2007 MSC.Software Corporation REVIEWING VIEWFACTOR OUTPUT l *.LOG FILE l VFMSG FILE l CONTROL DATA ECHO l REPORTS ON VIEWFACTOR l CALCULATIONS l REPORT ON RESISTOR CALCULATIONS l SUCCESSFUL EXECUTION COMPLETED l VFDIAG FILE l SURFACE CLOSURE DATA ID F1- F 0 NODAL SUBAREA F l STATISTICAL DATA l MAXAVGSDAVG || ||SD || ||

PAT312, Section 61, December 2006 S61-9 Copyright 2007 MSC.Software Corporation CHANGING SURFACE PROPERTIES AFTER VIEW FACTORS ARE CALCULATED l Change VFAC Templates l Changing material definitions in QTRAN'S MATDAT FILE (no need to make new resistors if templates are not changed) l Change in VFCTL l $RUN_CONTROL: 2 l Submit new MSC.Thermal VIEWFACTOR Job

PAT312, Section 61, December 2006 S61-10 Copyright 2007 MSC.Software Corporation

PAT312, Section 61, December 2006 S61-11 Copyright 2007 MSC.Software Corporation

PAT312, Section 61, December 2006 S61-12 Copyright 2007 MSC.Software Corporation