WS10-1 WORKSHOP 10 TRANSIENT ANALYSIS WITH RADIATION SOURCE AND CONVECTION NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation

WS10-2 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation

WS10-3 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation n Problem Description u A ceramic wall(3 cm x 3 cm) is initially at a uniform temperature of 20 C(293 K), and has a thickness of 1.0 cm. It is suddenly exposed to a radiation source on the right side at The emissivity and absorbtivity are equal to 0.8. The left side is exposed to room air at 20 C with h=1.92e-4*DT**0.25 Watt/(cm**2*C). Properties of the ceramic are k=3.0e-2 Watt/(cm*C), density= kg/cm**3, and specific heat=800 joule/(kg*C). Determine the temperature distribution in the plate over time.

WS10-4 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation n Suggested Exercise Steps 1. Create a database. 2. Create a geometric surface for subsequent meshing 3. IsoMesh the surface with four noded elements 4. Define material property 5. Define element property 6. Create a transient load case 7. Create Loads/BCs for radiation to ambient space 8. Create Loads/BCs for convection to ambient 9. Perform the thermal analysis 10. Attach XDB file 11. View the temperature results 12. Create XY plot for temperature versus time 13. Quit MSC.Patran

WS10-5 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 1: Create a Database Create a database. a.File/New… b.Enter tran_radsrce for File name. c.Click OK. d.Click Default for Tolerance in New Model Preferences. e.Specify MSC.Nastran Thermal f.Click OK. a f d b c

WS10-6 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 2: Create a Geometric Surface for Subsequent Meshing Create a surface to represent a wall. a.Geometry: Create/Surface/XYZ. b.Enter for Vector Coordinates List. c.Enter [0 0 0] for Origin Coordinates List. d.Click Apply. a b c d

WS10-7 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 3: IsoMesh the Surface With Four Noded Elements IsoMesh the surface with Quad4 topology.. a.Elements: Create/Mesh/Surface. b.Select Quad for Elem Shape. c.Select IsoMesh for Mesher. d.Select Quad4 for Topology. e.Select Surface 1 for Surface List. f.Enter 0.25 for Global Edge Length. g.Click Apply. a b c e f g d

WS10-8 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 4: Define Material Property Define the wall material. a.Materials: Create/ Isotropic/Manual Input. b.Enter wall for Material Name. c.Click Input Properties… d.Enter 0.03 for Thermal Conductivity. e.Enter 800 for Specific Heat. f.Enter for Density. g.Click OK h.Click Apply. a b c e f g d h

WS10-9 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 5: Define Element Property Create the 2D element property set. a.Properties: Create/2D/Shell. b.Enter ceramic for Property Set Name. c.Click Input Properties… d.Click in the Material Name and select wall under Material property sets. e.Enter 1 for Thickness. f.Click OK. g.Select Surface 1 for Select Members. h.Click Add. i.Click Apply. a b c e f d g h i

WS10-10 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 6: Create a Transient Load Case Create time dependent load case. a.Load Case: Create b.Enter tran for Load Case Name. c.Select Make Current. d.Select Time Dependent. e.Click Apply. a b d e c

WS10-11 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 7: Create Loads/BCs for Radiation to Ambient Space Create loads/BCs for radiation. a.Loads/BCs: Create/Radiation/Element Uniform. b.Select Ambient Space for Option. c.Enter rad for New Set Name. d.Select 2D for Target Element Type. e.Click Input Data. f.Enter 0.8 for Edge Emissivity g.Enter 0.8 for Edge Absorptivity. h. Enter 1273 for Ambient Temperature. i.Enter 1 for View Factor. j.Click OK. k.Click Select Application Region.. l.Select Surface 1.3 for Select Surfaces or Edges. m.Click Add. n.Click OK o.Click Apply a b c f g h e i j k l m o n d

WS10-12 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step: 8: Create Loads/BCs for Convection to Ambient Create loads/BCs for convection. a.Loads/BCs: Create/Convection/Element Uniform b.Select To Ambient for Option. c.Enter conv for New Set Name. d.Select 2D for Target Element Type. e.Click Input Data… f.Enter 1.92e-4 for Edge Convection Coef. g.Enter 293. for Ambient Temperature. h.Enter 0.25 for Convection Exponent. i.Click OK. j.Click Select Application region… k.Select Surface 1.1 for Select Surface or Edges. l.Click Add. m.Click OK. n.Apply. a b c e f g d h i j k l m n

WS10-13 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 9: Perform the Thermal Analysis Analyze the model. a.Analysis: Analyze/Entire Model/ Full Run. b.Enter t414 for Job Name. c.Click Solution Type. d.Select TRANSIENT ANALYSIS e.Click Solution Parameters… f.Enter 293 for Default Init Temperature. g.Click Radiation Parameters… h.Select E-12 WATTS/CM2/K4 i.Click OK 3 times. j.Click Subcases… k.Continued a b c e f g d h i j

WS10-14 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 9: Perform the Thermal Analysis (Cont.) a.Select tran for Available Subcases b.Select tran for Available Load Cases. c.Click Subcase Parameters. d.Enter 2 for Initial Time Step. e.Enter 100 for Number of Time Steps. f.Click Fixed Time Steps. g.Click OK. h.Click Apply/Cancel i.Click Subcase Select. j.Select tran for Subcases For Solution Sequence: 159. k.Click OK. l.Click Apply. e f g d a b c h i j k l

WS10-15 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 10: Attach XDB File Attach XDB results file. a.Analysis: Attach XDB/Result Entities/Local. b.Click Select Results File… c.Select t414.xdb. d.Click OK. e.Click Apply. a b c e d

WS10-16 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 11: View the Temperature Results View the temperature results. a.Results: Create/Quick Plot. b.Select SC1 TRAN, AT Time=108 for Select Result Cases. c.Select Temperature for Select Fringe Result d.Click Apply. a b c d

WS10-17 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 12: Create XY Plot for Temperature Versus Time Create temperature versus time plots. a.Results: Create/Graph/ Y vs. X b.Select all the result cases under Select Result Case(s). c.Select Temperature for Select Y Result. d.Click Target Entities. e.Enter Node for Select Nodes. f.Click Apply. a b c e f d

WS10-18 NAS104, Workshop 10, March 2004 Copyright 2004 MSC.Software Corporation Step 13: Quit MSC.Patran Quit MSC.Patran a.Select File on the Menu Bar and select Quit from the drop down menu a