S5-1 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation SECTION 5 TRANSIENT THERMAL ANALYSIS (SOL 159)

S5-2 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n This project comes from example 7c in the MSC.Nastran Thermal User Guide. n Objective: apply time varying volumetric heating to a single 1x1x1 CHEXA element. n HGEN=10.0 n Also, convect to ambient temperature at 0 degree C with a constant h of n Initially the solid is at zero degree

S5-3 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Specify QVOL as a function of time u Create a Non Spatial field named qvol_time

S5-4 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create a 1x1x1 solid. n IsoMesh the solid u Hex8 topology u GEL = 1.0

S5-5 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create a material property set for aluminum u K u Cp u Rho

S5-6 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Change the Constitutive Model to Heat generation n 10.0 is the factor by which the heat generation is multiplied

S5-7 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create 3D element property set u Aluminum u Solid 1

S5-8 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n To create a time dependent thermal load(e.g. applied heating) it is necessary to first create a time dependent load case. When this is done the LBC form in MSC.Patran will have the necessary entry lists for the transient inputs.

S5-9 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n The QVOL function is equal to * qvol_time(non spatial time dependent field)

S5-10 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create convection to ambient temperature u Constant convection coefficient h=100 u Ambient temperature is 0 C u No time function is used

S5-11 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) nPick all the faces at one time

S5-12 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME)

S5-13 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create a subcase under Subcases… u A subcase is automatically created for each load case that is created. They both have the same name. u It may be necessary to change some of the subcase settings, e.g. change some of the settings under Subcase Parameters… u It is possible to create a new subcase using the available load cases. When this is done specify the values for the various subcase parameters.

S5-14 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Under Subcase Select… select the subcase named tran for the transient analysis

S5-15 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Access the transient thermal analysis results by attaching the.xdb file to the MSC.Patran database.

S5-16 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) n Create a plot of temperature versus time at a node(s) n After selecting the result case (SC1:TRAN), result type(temperatures), X: Global Variable Time, then select the second icon at the top of the form Target Entities

S5-17 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME)

S5-18 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) SOL 159 TIME 600 CEND ANALYSIS = HEAT TITLE = MSC/NASTRAN job created on 08-Jul-98 at 16:41:04 ECHO = SORT MAXLINES = SPC = 1 IC = 1 SUBCASE 1 $ Subcase name : tran SUBTITLE=tran TSTEPNL = 1 DLOAD = 2 THERMAL(SORT2,PRINT)=ALL FLUX(SORT2,PRINT)=ALL Extracted from MSC.Nastran model.DAT file

S5-19 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) PSOLID CHEXA B + B 8 7 $ Referenced Material Records $ Material Record : alum $ Description of Material : Date: 08-Jul-98 Time: 16:15:34 MAT $ Nodes of the Entire Model GRID GRID GRID GRID GRID GRID GRID GRID Extracted from MSC.Nastran model.DAT file

S5-20 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) $ Loads for Load Case : tran TLOAD DLOAD $ Fixed Temperatures of Load Set : conv SPC $ Volumetric Heat Generation of Load Set : qvol QVOL $ Scalar Points SPOINT 9 $ Dynamic Load Table : qvol_time TABLED1 1 + C + C D + D ENDT Extracted from MSC.Nastran model.DAT file

S5-21 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) $ Initial Temperatures from Temperature Load Sets TEMP $ Default Initial Temperature TEMPD 1 0. $ CHBDYG Surface Elements CHBDYG 1 AREA4 + E + E CHBDYG 2 AREA4 + F + F CHBDYG 3 AREA4 + G + G CHBDYG 4 AREA4 + H + H CHBDYG 5 AREA4 + I + I CHBDYG 6 AREA4 + J + J Extracted from MSC.Nastran model.DAT file

S5-22 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) $ Convection to Ambient of Load Set : conv PCONV CONV CONV CONV CONV CONV CONV $ Free Convection Heat Transfer Coefficients MAT Extracted from MSC.Nastran model.DAT file

S5-23 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) 0 SUBCASE 1 POINT-ID = 3 T E M P E R A T U R E V E C T O R TIME TYPE VALUE 0.0 S E+01 S E E+01 S E E+01 S E E+01 S E E+01 S E E+01 S E E+01 S E E+01 S E E+01 S E E+02 S E E+02 S E-01 TSTEPNL ADAPT UPW n Deactivate the automatic adjustment(adaptivity) Extract from MSC.Nastran ASCII Results File Extracted from MSC.Nastran model.DAT file

S5-24 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation PROJECT 6 QVOL(TIME) $TITLE = MSC/NASTRAN JOB 49 $SUBTITLE=TRAN 50 $LABEL = 51 $DISPLACEMENTS 52 $REAL OUTPUT 53 $SUBCASE ID = 1 54 $TIME = E TEMP* E TEMP* E TEMP* E TEMP* E TEMP* E TEMP* E TEMP* E TEMP* E TEMP* E Extract from MSC.Nastran ASCII Punch File n Results in SORT1 format in punch file.

S5-25 NAS104, Section 5, March 2004 Copyright 2004 MSC.Software Corporation n Perform Workshop 8 Transient Thermal in the exercise workbook. n Perform Workshop 9 Transient Thermal Analysis of a Cooling fin in the exercise workbook. n Perform Workshop 10 Holman example 4-14, Radiation heating and cooling of ceramics in the exercise workbook. n Perform Workshop 11 Heating a block of ice cream in the exercise workbook EXERCISES