WORKSHOP 22 STEADY STATE RADIATIVE BOUNDARY CONDITIONS

WS22-2 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation

WS22-3 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Model Description In this exercise you will construct a model with two separate radiation enclosures, one for gray body radiation and the other for wave length dependent radiation. No material (e.g. air) will be defined in the enclosure therefore only Radiation heat transfer can transfer heat energy across the enclosures. In the enclosure where it is assumed that the surfaces are gray the emissivity will be constant regardless of the surface temperatures. The other enclosure will incorporate wave length dependent radiation which is a significant extension of the gray body theory. Normal radiosity is divided into discrete frequency bands with emissivity and transmissivity assumed to be constant within these frequency bands. Enclosure Emissivity Information Enclosure 1 Gray =0.9 Enclosure 2 For ( )=0.9 =0.4 For 5.0< ( )=0.2 =0.4

WS22-4 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Objectives Create a 2D model that incorporates two enclosures. Define separate radiative boundary conditions for gray body and wave length dependent radiation within the enclosures. Perform the Steady State thermal analysis and post process the analysis results with MSC.Patrans Result and Insight tools. Exercise Overview 1. Create a new database named exercise_22.db. Set Tolerance to Default and the Analysis Code to MSC/Thermal. 2. Create a plate geometry. 3. Mesh the surface with an IsoMesh of quad4 elements, global edge length of Equivalence nodes to eliminate duplicate nodes and eliminate cracks in the mesh. 5. Create a fixed temperature boundary nodes. 6. Apply Temperature boundary conditions. 7. Apply View Factor boundary conditions. 8. Define the Element Properties for the models Iron material. 9. Prepare and submit the model for analysis. 10. Read and plot results. 11. Create Temperature and Insight Contours. 12. Quit MSC.Patran.

WS22-5 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 1: Create a New Database Create a new database called exercise_22.db. a. File: New. b. Enter exercise_22 as the file name. c. OK. d. Choose Default Tolerance. e. Select MSC.Patran Thermal as Analysis Code. f. Select Thermal as Analysis Type. g. OK. a b c d e f g

WS22-6 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 2: Create Plane Geometric Surfaces Create plane geometric surfaces. a. Geometry. b. Create/Surface/XYZ. c. Enter for Vector Coordinate List. d. Deselect Auto Execute. e. Apply. f. Enter for Vector Coordinate List. g. Select Point 4 for Origin Coordinates List. h. Apply. i. Enter for Vector Coordinate List. j. Select Point 6 for Origin Coordinates List. k. Apply. b c d e a

WS22-7 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 2: Create Plane Geometric Surfaces (Cont.) Create plane geometry surfaces. (continued) a. Geometry. b. Transform/Surface/Mirror. c. Enter Coord 0.1 for Define Mirror Plane Normal. d. Enter 1.0 for Offset Parameters. e. Select Surface 1:2 for Surface List. f. Apply. g. Enter Coord 0.2 for Define Mirror Plane Normal. h. Enter 0.8 for Offset Parameters. i. Select Surface 1:5 for Surface List. j. Apply. a b c d e f

WS22-8 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Continue to create a plate geometry. a. Create/Surface/Curve. b. Select Surface 1.2 for Starting Curve List. c. Select Surface 6.3 for Ending Curve List. d. Apply. e. Select Surface 3.2 for Starting Curve List. f. Select Surface 8.3 for Ending Curve List. g. Apply. h. Select Surface 9.2 for Starting Curve List. i. Select Surface 4.3 for Ending Curve List. j. Apply. a b c d Step 2: Create Plane Geometric Surfaces (Cont.)

WS22-9 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Check surface normals to verify that they are all in the +Z direction. a. Change to Iso 1 View. b. Geometry. c. Show/Surface/Normal. d. Select all surfaces for Surface List. e. Apply. f. If there are any surfaces pointing in the -Z direction change them by using Edit/Surface/ Reverse. g. Select any surface that needs to be reversed for Surface List. h. Apply. b c d e a Step 2: Create Plane Geometric Surfaces (Cont.)

WS22-10 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 3. Mesh the Geometric Surfaces Mesh the surfaces using IsoMesh with Quad4 elements. a. Finite Elements. b. Create/Mesh/Surface. c. Enter for Global Edge Length. d. Select Surface 1:13 for Surface List. e. Apply. f. Return to the front view and turn off all labels using the following icons. a b c d e f

WS22-11 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 4. Equivalence the Nodes Equivalence nodes to connect adjacent elements at geometric interfaces. a. Equivalence/All/Tolerance Cube. b. Apply. c. Verify/Element/Boundaries. d. Apply. a c d a

WS22-12 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 5: Create a Boundary Node Create a fixed temperature boundary node. a. Finite Elements. b. Create/Node/Edit. c. Enter 1000 for Node ID List. d. Deselect Associate with Geometry. e. Enter [ ] for Node Location List. f. Apply. g. Increase the size of the node markers. a b c d e f g

WS22-13 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 6: Apply Temperature Boundary Conditions Apply temperature boundary conditions. a. Loads/BCs. b. Create/Temperature/ Nodal. c. Select Fixed for Option. d. Enter Temp_Part_Med for New Set Name. e. Click Input Data… f. Enter 200 for Fixed Temperature. g. OK. h. Click Select Application Region… i. Select FEM Filter. j. Select Node 1000 for Select Node. k. Add. l. OK. m. Apply. a b c d e f g h i j l m k

WS22-14 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 6: Apply Temperature Boundary Conditions (Cont.) Assign fixed temperature to the top and bottom geometry edges of the model. a. Enter T_top for New Set Name. b. Click Input Data… c. Enter 1500 for Fixed Temperature. d. OK. e. Click Select Application Region… f. Select Geometry Filter. g. Select the top edges for Select Geometry Entities by using the Curve or Edge icon in the select menu. h. Add. i. OK. j. Apply. a b c d e f g i j h

WS22-15 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 6: Apply Temperature Boundary Conditions (Cont.) Assign fixed temperatures to the top and bottom geometry edges of the model. (continued) a. Enter T_bottom for New Set Name. b. Click Input Data… c. Enter 0 for Fixed Temperature. d. Click OK. e. Click Select Application Region… f. Select Geometry Filter. g. Select the bottom edges for Select Geometry Entities by dragging a box around the entities. h. Add. i. OK. j. Apply. c a j g h d b i f e

WS22-16 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 7: Apply Radiation Boundary Conditions Apply radiation boundary conditions. a. Loads/BCs. b. Create/Radiation/Element Uniform. c. Select Template,View Factors for Option. d. Enter Encl_101 for New Set Name. e. Select 2D for Target Element Type. f. Click Input Data… g. Enter 1 for Enclosure ID. h. Enter 100 for VFAC Template ID. i. OK. j. Click Select Application Region… k. Select the Geometry Filter. l. Referring to the diagram of this page, drag a box around the interior surface edges corresponding to Label 101. m. Add. n. OK. o. Apply. a b c d e f g h i j k n o l l m

WS22-17 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Apply View Factor boundary conditions. a. Enter Encl_201 for New Set Name. b. Select 2D for Target Element Type. c. Click Input Data… d. Enter 2 for the Enclosure ID. e. Enter 200 for VFAC Template ID. f. Select Node 1000 for Participating Media Node ID. g. OK. h. Click Select Application Region… i. Select the Geometry Filter. j. Referring to the diagram on this page, drag a box around the interior surface edges corresponding to Label 201. k. Add. l. OK. m. Apply. a b c h m i k l d e f g j j Step 7: Apply Radiation Boundary Conditions (Cont.)

WS22-18 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 8: Model With all Boundary Conditions

WS22-19 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 9: Create File template.dat.apnd Complete the view factor definitions by using Analysis: Build Template form. a. Analysis. b. Build template c. Create Template File… d. Create/VFAC/Data Entry. e. Enter 100 for VFAC ID. f. Enter 0.9 for Emissivity. g. Enter 0 for [Collapse Flag ID]. h. Apply. i. When the spreadsheet form is displayed, Cancel. j. Select Wavelength Dependent. k. OK. l. Enter 200 for VFAC ID. m. Click Advanced Options… n. Enter 2 for No. Wavebands. o. Enter 0.9 for Ec, press Enter. p. Enter the remaining information for the TID 200 row from the table. q. OK. r. Apply. s. Write File… t. Enter template.dat.apnd. u. OK. v. Cancel. w. Cancel. id 1 2 K flagCollapse E600 TIDNBANDS 2002 d e f g h n o

WS22-20 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 10: Define Element Properties Define the element properties for the models Iron material. a. Properties. b. Create/2D/Thermal 2D. c. Enter Iron for Property Set Name. d. Click Input Properties… e. Enter 18 for Material Name. f. OK. g. Select Surface 1:13 for Select Members. h. Add. i. Apply. a b c d e f g i h

WS22-21 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 11: Prepare and Run Analysis Prepare and submit the model for analysis. a. Analysis. b. Analyze/Full Model/Full Run. c. Click Translation Parameters… d. Select 2D Plane Geometry, XY Co- ordinate (Unit Thickness in Z). e. OK. f. Click Solution Type… g. Select Perform Viewfactor Analysis. h. OK. i. Click Solution Parameters… j. Select Celsius for Calculation Temperature Scale. k. OK. l. Click Output Requests… m. Select Celsius for Units Scale for Output Temperatures. n. OK. o. Submit Options… p. Select Create Viewfactor Control File and Execute Viewfactor Analysis. q. OK. r. Apply. a b c d f g i j l m o r

WS22-22 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 12: Read and Plot Results Read and plot the results. a. Analysis. b. Read Result/ Result Entities. c. Click Select Results File… d. Under directories, find the path the leads to exercise_22. e. Under available files select nr0.nrf.01. f. OK. g. Click Select Rslt Template File… h. Select pthermal_1_nodal. res_tmpl. i. OK. j. Apply. a b c d f g h i j e

WS22-23 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Read and Plot the results. a. Results. b. Set to Create/Quick Plot. c. Select Time: D+ 00S…for Select Result Cases. d. Select Temperature for Select Fringe Result. e. Reduce the Node size. f. Select the Fringe Attributes icon. g. Select Element Edges for Display. h. Click Label Style. i. Select Fixed for Label Format. j. Use the slider bar to select 4 Significant figures. k. OK. l. Apply. a e i j k b g h l Step 12: Read and Plot Results (Cont.)

WS22-24 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 12: Read and Plot Results (Cont.)

WS22-25 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 13: Create Temperature Contours Create temperature contours. a. Reset Graphics. b. Results. c. Create/Contour/Lines. d. Results Selection… e. Select the result case. f. Select Temperature g. Apply. a b c g d e f

WS22-26 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Create Cursor. a. Reset Graphics. b. Create/Cursor/Scalar. c. Apply d. The cursor summary form appears e. Click within the viewport to display cursor results. b c g Step 14: Create Temperature Cursor Plot a d

WS22-27 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation Step 15: Quit MSC.Patran Quit MSC.Patran. a. Select File. b. Click Quit from the drop down menu.

WS22-28 PAT312, Workshop 22, December 2006 Copyright 2007 MSC.Software Corporation