Introduction to Thermal Analysis Using MSC.thermal

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Introduction to Thermal AnalysisUsing MSC.Thermal

PAT312 EXERCISE WORKBOOKMSC.Patran Version 2001

P3*V2001*Z*Z*Z*SMPAT312WBK

June 2001

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Copyright 2001 MSC.Software

TABLE OF CONTENTSMSC.Patran

Introduction to Thermal Analysis Using MSC.ThermalPAT312

Exercise Workbook Release 2001

Workshop Title

Exercise 1 Construct Hybrid Microcircuit Geometry . . . . . . . . . . .1-1Geometry Creation

Exercise 2 Hybrid Microcircuit Finite Elements. . . . . . . . . . . . . . . .2-1Meshing

Exercise 3 Equivalence and Verify the Hybrid Mesh . . . . . . . . . . . .3-1FEM Verification Tools

Exercise 4 Materials, Lists and Groups. . . . . . . . . . . . . . . . . . . . . . .4-1Define material properties using lists and groups

Exercise 5 Thermal Analysis using Imported CAD Geometry. . . . .5-1Create and analyze model with imported geometry

Exercise 6 Comparison of Two Heat Sink Designs . . . . . . . . . . . . .6-12D axisymmetric model with simple convection

Exercise 7 An Oven Window Design . . . . . . . . . . . . . . . . . . . . . . . .7-12D planar model with field definition for LBC, simpleconvection

Exercise 8 Temperature Dependent Material Properties. . . . . . . . . .8-12D planar model with field definition for materialproperties

Exercise 9 Thermal Analysis of the Hybrid Microcircuit . . . . . . . . .9-1Create convection and loading LBCs, submit analysisand view results

Exercise 10 Time Dependent Boundary Conditions . . . . . . . . . . . . . .10-1Using microfunctions for transient analysis

Exercise 11 Using Convection Correlations . . . . . . . . . . . . . . . . . . . .11-1Using the convection correlation library

Copyright 2001 MSC.Software

Workshop Title

Exercise 12 Analysis of a Fuel Nozzle Tip . . . . . . . . . . . . . . . . . . . . .12-1Advective, radiative and convective boundaries,convective quads

Exercise 13 A Sprinkler System Hydraulic Analysis . . . . . . . . . . . . .13-1Pressure varying mass flow

Exercise 14 Midterm: Build a Simple 2 Plate Model . . . . . . . . . . . . .14-1Radiation heat transfer, analysis utilities

Exercise 15 User Supplied Subroutines . . . . . . . . . . . . . . . . . . . . . . .15-1User subroutine convection calculations

Exercise 16 A Concentric Tube, Counterflow Heat Exchanger . . . . .16-1Element sweep, gap convection

Exercise 17 Analysis of a Fuel Nozzle Tip Using ConvectionBetween Regions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17-1Advective, radiative and convective boundaries

Exercise 18 Post-processing the Hybrid Microcircuit Resultswith Insight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18-1Insight tools

Exercise 19 Animating Results with Insight . . . . . . . . . . . . . . . . . . . .19-1Insight and Patran animation

Exercise 20 SINDA Translation of a PWB Model . . . . . . . . . . . . . . .20-1Read session file, produce SINDA deck

Exercise 21 Optimizing Performance of RadiationInterchange Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . .21-1Flags and settings to increase run efficiency

Exercise 22 Steady State Radiative Boundary Conditions . . . . . . . . .22-12D planar model with radiation within enclosures

Exercise 23 Your Model Here . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23-1User initiated model

MSC.Patran 312 Exercise Workbook - Release 2001 1-1

WORKSHOP 1

Construct HybridMicrocircuit Geometry

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6 7

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1

X

Y

Z

Objective:n In this exercise you will construct a trimmed surface which

will be the underlying geometry of a 3D Hybrid Microcircuitmodel.

n Create a trimmed surface with interior cutouts forcomponents.

n Create regular surfaces representing component footprints.

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6 7

2 3 4 5

1

1-2 MSC.Patran 312 Exercise Workbook - Release 2001

WORKSHOP 1 Construct Hybrid Microcircuit Geometry


Model Description:In this exercise you will create the required geometry for a 3Dhybrid microcircuit model. You will first construct simple surfaceswhich will define the microcircuit perimeter and the locations ofeight surface mounted devices. From the edges of these simplesurfaces you will create chained curves which define the inner andouter edges (loops) of the microcircuit surface. From these chainedcurves you will create a trimmed surface, the guiding geometry ofthe microcircuit model.

In later exercises you will define the finite element mesh, materialproperties, thermal loads, and boundary conditions for themicrocircuit.

Exercise Overview:n Create a new database named microcircuit.db. Set

the Tolerance to Based on Model, the ApproximateMaximum Model Dimension to 0.02, and theAnalysis Code toMSC/THERMAL.

n Create a simple surface that will form the outsideedge for the microcircuit model. The dimensions areprovided.

n Turn labels on using Tool Bar Show Labels icon.

n Create eight regular surfaces that will define thelocations of the surface mounted devices. Thedimensions are provided.

n Create chained curves on the edges of each surface byusing Create/Curve/Chain.

n Unclutter the display by selectively hiding labels.

n Complete the geometry of the hybrid microcircuit byusing Create/Surface/Trimmed with the OptionPlanar.

n QuitMSC.Patran.

.

Hybrid Microcircuit Dimensions


Exercise Procedure:1. Create a new database named microcircuit.db. Set

the Tolerance to Based on Model, the ApproximateMaximum Model Dimension to 0.02, and theAnalysis Code toMSC/THERMAL.

Within your window environment change directories to aconvenient working directory. Run MSC.Patran by typingp3 in your xterm window.

Next, select File from the Menu Bar and select Newfrom the drop-down menu.

Assign the name microcircuit.db to the new database byclicking in the New Database Name box and enteringmicrocircuit (.db will automatically be appended).Select OK to create the new database.

HybridMicrocircuit

0.02

0.004

0.0094

0.0026

0.004 0.004

0.02

0.002 X 0.002(typical)

0.006 X 0.001(typical)

(All lengths shown in meters)

0.004 0.002

Figure 1 -Board Design

Create anewdatabase



MSC.Patran will open a Viewport and change variousControl Panel selections from a ghosted appearance to abold format.When the New Model Preferences form appearson your screen, set the Tolerance to Based on Model, theApproximate Maximum Model Dimension to 0.02, and theAnalysis Code to MSC/THERMAL. Select OK to closethe New Model Preferences form.

2. Create a simple surface that will form the outsideedge for the microcircuit model.

Select the Geometry toggle in Applications radio button.You will now create a 0.02 X 0.02 surface. Use its outsideedges to form the outer loop for the trimmed surface youwill create in the last part of this exercise.

Set the Action, Object, and Method to Create/Surface/XYZ. Be sure to turn off Auto Execute in all forms in thisexercise. Change the Vector Coordinates List to and select Apply to create the surface. Thecompleted form is shown below.

Create asimplesurface

GeometryAction: Create

Object: SurfaceMethod: XYZ

Surface ID List1

Surface Type

PATRAN 2 Convention

Refer. Coordinate FrameCoord 0

Vector Coordinates List

Auto Execute

Origin Coordinates List[0 0 0]

-Apply-

Turn on labels


3. Turn labels on using Tool Bar Show Labels icon.

Use the Tool Bar Show Labels icon on the menu bar to turnon labels. The correct model is shown below.

4. Create eight regular surfaces that will define thelocations of the surface mounted devices.

Position the left-most square device by changing theVector and Origin Coordinates Lists to and [0.004 0.004 0]. Select Apply to create the surface.

Turn onlabels

X

Y

Z 1

2 3

4

1

Positionthe 8devices



Create three copies of this region by changing the Action,Object, and Method to Transform/Surface/Translate.Enter for the Translation Vector and 3 for theRepeat Count. Click in the Surface List box. SelectSurface 2 in the viewport. Select Apply to create thesurface. The completed Geometry form and current modelshould appear as shown below.

Leaving the Action as Transform change the Object andMethod to Point/Translate. Edit the Translation Vector toread and the Repeat Count to 1. Click in thePoint List box and select Point 5 from the viewport, thelower left corner point of Surface 2. Select Apply to createthe surface. Point 21 should appear to guide layout of theremaining four devices.

Geometry

Surface ID List3

Type of TransformationCartesian in Refer. CFCurvilinear in Refer. CF


Translation ParametersRepeat Count3

Delete Original SurfacesAuto ExecuteSurface List

-Apply-

Translation Vector

uuu

Surface 2

Action: TransformObject:Method:Object: Surface

Translate

1

2 3

4

5

6 7

8 9

10 11

1213

14 15

16 17

18 19

20

1

3 4 52

X

Y

Z

Position the 8 devices


Set the Action, Object, and Method to Create/Surface/XYZ. Position the first rectangular device by changing theVector Coordinates List to , clicking in theOrigin Coordinates List box, and selecting Point 21 fromthe viewport. Select Apply to create the surface.

After constructing Surface 6 use the Transform/Surface/Translate operations twice to complete theremaining three device locations. Forms are shownbelow.

GeometryAction: CreateObject: SurfaceMethod: XYZ

Surface ID List6Surface Type

PATRAN 2 Convention


Vector Coordinates List

Auto ExecuteOrigin Coordinates ListPoint 21

-Apply-

Geometry

Surface ID List7

Type of TransformationCartesian in Refer. CFCurvilinear in Refer. CF




-Apply-

Translation Vector

uuu

Surface 6


Translate

Geometry

Surface ID List8Type of Transformation

Cartesian in Refer. CFCurvilinear in Refer. CF




-Apply-

Translation Vector

uuu

Surface 6 7


Translate



Your model should now appear as shown below.

5. Create chained curves on the edges of each surface.

In order to facilitate picking, use Preferences/Picking...and set Rectangle/Polygon Picking to Enclose entireentity. Select Close. Next, Change the Action, Object, andMethod to Create/Curve/Chain. Turn off the DeleteConstituent Curves option. To create the perimeter chainclick in the Curve List box and then click in the Edgeselection icon (third from the top) in the Select Menu.While holding the key down select the four outeredges of Surface 1. The completed form should now looklike the one shown below.

Select Apply to complete the function.

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14 15

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26 27

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Y

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Createchainedcurves

GeometryAction: CreateObject: CurveMethod: Chain

Curve ID List1

Auto Chain...Delete Constituent Curves

Curve List

-Apply-

Surface 1.1 1.2 1.3 1.4

Unclutter the display


To create the 8 interior chained curves click in the CurveList box and drag a rectangle around Surface 2 (the lowerleft-most device location). The 4 edge identifiers forSurface 2 should replace the previous Curve List box entry.Select Apply to complete the function. Repeat this stepfor the remaining seven device surfaces.

6. Unclutter the display by hiding some labels.

To simplify the displayed image of your model selectDisplay from the Menu Bar and select Entity Color/Label/Render... from the drop-down menu. When theEntity Color/Label/Render Display form appears select HideAll Entity Labels and turn on only Curve, Surface, andTSurf labels. Select Apply then Cancel to complete thefunction.

Your model should now appear as shown below.

7. Complete the geometry of the hybrid microcircuit.

Create the trimmed surface that surrounds themicrocircuits devices. Set Action, Object, and Method toCreate/Surface/Trimmed. Select Option as Planar. Turnoff theDelete Outer and Inner Loops switches. Click in theOuter Loop List databox, click in the Curve selection icon(second from the top) in the Select Menu and select

Unclutterthedisplay

2 3 4 5

6 7

8 9

1

X

Y

Z

8 9

6 7

1

2 3 4 5

Create atrimmedsurface



Curve 1. Next, click in the Inner Loop List databox anddrag a rectangle around Curves 2 through 9. Thecompleted Geometry form is shown below for yourreference.


Your model should now appear as shown on the front panelof this exercise.

If it does not, selectViewing from theMenu Bar and selectFit View from the drop-down menu.

8. Quit MSC.Patran.To stopMSC.Patran select File on theMenu Bar and selectQuit from the drop-down menu.

GeometryAction: Create

Object: SurfaceMethod: Trimmed

Option:

Surface ID List10

Surface TypePATRAN 2 Convention

Planar

Auto Chain...Use All Edge VerticesDelete Outer Loop

Outer Loop List

Delete Inner Loops

Inner Loop List

-Apply-

Curve 1

Curve 2:9

QuitMSC.Patr

Quit MSC.Patran



WORKSHOP 2

Hybrid Microcircuit FiniteElements

Objective:n In this exercise you will mesh the 3D Hybrid Microcircuit

model in two steps.

n You will use both the IsoMesh and Paver mesher options tocreate a surface mesh. These surface elements will then beswept into solid elements.

WORKSHOP 2 Hybrid Microcircuit Finite Elements


Model Description:In this exercise you will create a mesh for the 3D hybridmicrocircuit model. You will use a finite element constructionmethod called 2 1/2 D-meshing to create your 3D finite elementmodel. This algorithm is an extension to the IsoMesh or Paveralgorithms because it will create elements where no geometryexists.

The mesh will be created in a two step process. First the surfacegeometry will be meshed using both the IsoMesh and Paveroptions. The resulting surface elements will be used as a templateto create a solid mesh of hexahedral elements. Finally thequadrilateral surface elements are deleted.

Exercise Overview:n Open the existing database namedmicrocircuit.db.

n Using Show/Surface/Normal verify that all surfacenormals point in the +Z direction. If necessary, editnormals using Edit/Surface/Reverse.

n Delete Surface 1 by using Delete/Any and selectingSurface 1.

n Mesh the regions containing the devices usingCreate/Mesh/Surface and the IsoMesh Mesher.

n Sweep/Element/Normal to create device hexelements.

n Switch to the Paver Mesher and mesh the remainingtrimmed surface geometry.

n Sweep/Element/Normal with One Way Bias in the- Z direction from all surface quads to createsubstrate hex elements.

n Use Finite Elements/Delete/Any and the SelectMenu filter to delete all surface quad elements.

n Unclutter the display by hiding labels.

n QuitMSC.Patran.

.

Open an existing database


Exercise Procedure:1. Open the existing database named microcircuit.db.

Within your window environment change directories to themicrocircuit.db working directory. Run MSC.Patran bytyping p3 in your xterm window.

Next, select File from the Menu Bar and select Openfrom the drop-down menu. Select the namemicrocircuit.db from the Database List box.Select OK toopen the database.

MSC.Patran will open a Viewport and change variousControl Panel selections from a ghosted appearance to abold format.

From the Menu Bar select Viewing/Named ViewOptions... Select isometric_view then Close. SelectViewing/Fit View to readjust the display, if necessary.This will provide a convenient view for verifying normalvectors.

2. Verify that surface normals point in the +Z direction.

Select the Geometry Applications radio button. Set theAction, Object, and Method to Show/Surface/Normal.Select Set Normal Vector Length and enter a NormalVector Length of 0.01. Click in the Surface List box anddrag a rectangle around all the displayed geometry. SelectApply.

All normal vectors should point in the global +Zdirection.

Open anexistingdatabase

Verifysurfacenormals



If some surfaces have incorrect normal vectors use Edit/Surface/Reverse in the Geometry form, as shown below, topoint the normals in the +Z direction.

3. Delete Surface 1.

Set the Action and Object to Delete/Any. Click in theGeometric Entity List box and select Surface 1 from theviewport. Use the shift-right mouse button to cycle pickbetween Surface 10 and Surface 1 or select Surface 1 fromthe Selection list window, if necessary. Select Apply todelete Surface 1. Repaint the screen with the RefreshGraphics paint brush icon.

GeometryAction: EditObject: SurfaceMethod: Reverse

Reverse AssociatedElements

Surface List

Draw Normal VectorsReset Graphics

-Apply-

Auto Execute

DeleteSurface 1

IsoMesh device regions


4. Mesh the device regions with an IsoMesh.

Select the Finite Elements Applications radio button. Setthe Action, Object, and Type to Create/Mesh/Surface. SettheGlobal Edge Length to 0.0012. Click in the Surface Listbox and while holding down the key select theeight interior device surfaces with the left mouse button.The completed form is shown below.

Select Apply to complete the meshing function. Thedisplay should appear as shown above. If it does not, selectthe undo icon and analyze the error to a resolution.

IsoMeshdeviceregions

Finite ElementsAction: CreateObject: MeshType:Type: Surface

Output IDsNode ID List1

Element ID List1

Global Edge Length0.0012

Element Topology

Quad5Quad8

MesherIsoMesh Paver

IsoMesh Parameters...

Node Coordinate Frames...

Surface ListSurface 2:9

-Apply-

u uu

Quad4

X

Y

Z

1

2 3 4 5

67

89

10

2 3 4 5

67

89



5. Create device hex elements.

Set the Action, Object, and Method to Sweep/Element/Normal. (If the Mesh Control form appears click OK toaccept the defaults.) Change the Normal Length to 0.001.Click in the Base Entity List box and drag a rectanglearound the eight sets of quad elements. Select Apply tocomplete the meshing function. The completed form andresultant display are shown below.

6. Mesh the remaining trimmed surface with Paver.

Set the Action, Object, and Method to Create/Mesh/Surface. The Global Edge Length should be set to 0.0012.Select Paver as the Mesher option. Click in the SurfaceList box and select the remaining unmeshed trimmedsurface, Surface 10. SelectApply to complete the function.If you experience any problems selecting Surface 10, usePreferences/Picking.../(Single Picking) Centroid.

Createdevicehexelements

Finite ElementsAction: SweepObject:Method:

ElementNormal

Output IDsElement ID List37

Node ID List85

FE Parameters...

Mesh Control...Normal Length0.001

Offset0.0

Reverse Normal Direction

Delete Original Elements

Base Entity ListElm 1:36

-Apply-

1

2 3 4 5

67

89

10

X

Y

Z

Create thesubstratePaver

Create the substrate hex mesh


7. Sweep a one-way-biased mesh of hex elements inthe - Z direction from all surface quads.

Set the Action, Object, and Method to Sweep/Element/Normal. (If the Mesh Control form does not appear click onMesh Control...) In the Mesh Control form change theMethod to One Way Bias set Number to 3 and L2/L1 to 4.Select OK to close the Mesh Control form.

In the Finite Elements form set Normal Length to 0.005 andturn on Reverse Normal Directions. Click in the BaseEntity List box and drag a rectangle around all of theelements in the viewport. (The default Select Menu filterwill allow selection of only the quad/tri elements.) Theform should appear as shown below.

Select Apply to complete the meshing function. Theresultant display is shown above.

Create thesubstratehex mesh

Finite ElementsAction: SweepObject:Method:

ElementNormal

Output IDsElement ID List400

Node ID List611

FE Parameters...

Mesh Control...Normal Length0.005

Offset0.0

Reverse Normal Direction

Delete Original Elements

Base Entity ListElm 1:36 109:424

-Apply-

Mesh ControlMethod:One Way Bias

Mesh Control Data

Num Elems and L2/L1L1 and L2

Number = 3L2/L1 = 4

OK

L2L1

uuu

1

2 3 4 5

67

89

10

X

Y

Z



8. Delete all surface quad elements.

In the Finite Elements form set Action and Object toDelete/Any.

Click in the Finite Element Entity List box. In the SelectMenu choose the quad element filter icon (third from thetop), in the second level Select Menu choose the quadelement filter (fifth from the top), and drag a rectanglearound all entities displayed in the viewport. The formshould now appear as shown below.


Delete allquadelements

Finite Elements

Action: Delete

Object: Any

DeleteNode and Related

Empty GroupsElement and Related

NodeEmpty Groups

MPC'sNodeEmpty Groups

Auto ExecuteFinite Element Entity ListElm 1:36 109:424

-Apply-

Unclutter the display


9. Unclutter the display by hiding labels.

To simplify the display of your model select Display fromtheMenu Bar and select Plot/Erase... from the drop-downmenu. When the Plot/Erase form appears select PostedEntities/Geometry:Erase. Select OK to close the form.

Select Display from the Menu Bar and select EntityColor/Label/Render from the drop-down menu. Whenthe Entity Color/Label/Render form appears select Hide AllEntity Labels. Click in the Render Style: box and selectHidden Line or use Hide Labels and Hidden Line iconsshown to the right. Select Apply then Cancel to completethe function.

Your model should now appear as shown on the front panelof this exercise. Reset the Render Style toWireframe.

10. Quit MSC.Patran.Select File on theMenu Bar and selectQuit from the drop-down menu.

Unclutterthedisplay

QuitMSC.Patr


WORKSHOP 3

Equivalence and Verify theHybrid Mesh

X

Y

Z

Objective:n In this exercise you will equivalence the 3D Hybrid

Microcircuit model mesh.

n You will sample the finite element verification functions toexamine the aspect ratio, skewness, and taper of the meshelements.

WORKSHOP 3 Equivalence and Verify the Hybrid Mesh


Model Description:The hybrid microcircuit is monolithic: all material interfaces havenegligible resistance to heat transfer. Hence, there are no contactresistances modeled in the structure and the entire model ismaterially continuous. In this exercise you will identify anyincongruities, cracks, in the finite element mesh and equivalenceto eliminate them.

You will examine the completed mesh with quantitativeverification tools. You will evaluate the mesh element aspect ratio,taper, and skewness. These are generally useful in qualitativelyassessing the accuracy of results and identifying problem areas forconvergence to a solution.


n Use Finite Element/Verify/Element/Boundaries toidentify any cracks which remain as artifacts fromthe geometry creation and meshing process.

n Equivalence/All/Tolerance Cube to eliminateduplicate nodes and eliminate cracks in the mesh.

n Verify/Hex/Aspect to identify elements with aspectratios greater than 3.0.

n Verify/Hex/Face Skew to identify elements withface skew angles greater than 110 degrees.

n Verify/Hex/Face Taper to identify elements withhighly tapered faces.

n QuitMSC.Patran.

Open an existing database


Exercise Procedure:1. Open the existing database


Next, select File from the Menu Bar and select Open...from the drop-down menu. Select the namemicrocircuit.db from the Database List box.

Select OK to open the database.

MSC.Patran will open a Viewport and change variousControl Panel selections from a ghosted appearance to abold format.

2. Identify any cracks which remain as artifacts fromthe geometry creation and meshing process.

To identify mesh boundaries select the Finite ElementsApplications radio button. Set the Action, Object, and Testto Verify/Element/Boundaries. Select Apply. Thedisplay should appear as shown below.

3. Equivalence nodes to eliminate duplicate nodes andeliminate cracks in the mesh.

Set the Action, Object, and Method to Equivalence/All/Tolerance Cube. Select Apply to complete the function.


Identifycracks inmesh

X

Y

Z

Equivalence meshnodes



The nodes bounding the interior cracks will be circled inthe display and the Command Line will indicate that anumber of nodes are deleted.

Reexamine the mesh boundaries after equivalencing withVerify/Element/Boundaries. Your model should appearas shown on the front panel of this exercise.

4. Identify elements with aspect ratios greater than 3.0.

In the Finite Elements form set the Action, Object, and Testto Verify/Hex/Aspect. Change the Aspect Ratio toapproximately 3.0. Select Apply. Since the paver mesherwas used your results may vary from those shown below.Now select Plot Failed Elements Only. The completedform and resultant display are shown below.

Evaluateelementaspect

Finite ElementsAction: VerifyObject:Object: HexType: Aspect

Reliability Threshold

Normalize

Analysis Code:MSC/THERMAL

20.0.

Element Plot OptionsColor Code Elements

Plot Failed Elements Only

Fringe Attributes...

Apply Reset

3.07

Aspect Ratio

h2h1h2h1

Reset Graphics

Evaluate element face skewness


MSC.Thermal is reliable in converging to a solution evenwith elements of relatively high aspect ratio. However it isleft to the analyst to decide whether too large a gradient isresolved across the long dimension of a high aspect ratioelement. If this is so then resolving the mesh to a loweraspect ratio in that area will yield more accuracy.

5. Identify elements with face skew angles greater than110 degrees.

In the Finite Elements form set the Action, Object, and TesttoVerify/Hex/Face Skew. Change the Face Skew Angle toapproximately 20.0. Select Apply. Since the paver mesherwas used your results may vary from those shown below.Now select Plot Failed Elements Only. The completedform and resultant display are shown below.

Evaluateelementface

Finite ElementsAction: VerifyObject:Object: HexType: Face Skew


Normalize


90.0.




Apply Reset

20.05

Face Skew Angle

(90 )-

Reset Graphics



The finite element formulation of an R-C network inMSC.Thermal has been developed to provide a higherorder accuracy to the resultant temperature distributionthan is available with the traditional lumped mass/elementcentroid technique. Hence, even meshes with skewedelements yield results which do not contain artifacts of themesh geometry.

6. Identify elements with highly tapered faces.

In the Finite Elements form set the Action, Object, and Testto Verify/Hex/Face Taper. Change the Face Taper toapproximately 0.90. Select Apply. Since the paver mesherwas used your results may vary from those shown below.Now select Plot Failed Elements Only. The completedform and resultant display are shown below.

Evaluateelementface taper

Finite ElementsAction: VerifyObject:Object: HexTypet: Face Taper


Normalize


1.0.



Reset Graphics

Apply Reset

.90

Face Taper

a4 aA


Quit MSC.Patran


The verification functions in MSC.Patran provide a toolfor quantifying the geometric quality of a finite elementmesh. The criteria which determine the performance of themesh in a numerical analysis remain the province of theanalyst and his or her experience with the particularanalysis.

Click Reset Graphics in the Finite Elements Verify form.

7. Quit MSC.Patran.To stopMSC.Patran select File on theMenu Bar and selectQuit from the drop-down menu.

QuitMSC.Patr


WORKSHOP 4

Materials, Lists, and Groups

Objective:n In this exercise you will define material properties and apply

them as element properties on the hybrid microcircuit mesh.

n You will also use lists and groups as tools to more easilymanipulate your model.

WORKSHOP 4 Materials, Lists, and Groups


Model Description:In this exercise you will define several groups which will containsubsets of model entities. These groups can facilitate modelmanipulation. You will define materials by entering the datamanually based on the information provided These materials willbe applied as element properties. Lists will be used to demonstratetheir utility in completing the application and verification ofelement properties.

As you progress, carefully review your steps to ensure that youhave repeated each step, if necessary, for each material, group, andproperty definition.


n Use Create//Isotropic/Manual Input to define thefive materials used in this model.

n UseGroup/Create to define a group containing onlygeometry, another containing only FEM entities, andtwo more groups dividing the substrate FEM and thedevice FEM.

n Use Properties/Create/3D/Thermal 3D Solid toapply the material properties to 4 of the 5 materialregions; intentionally ignore the silicon region.

n Use List/Create... and List/Boolean...to identifyelements which have not had a material propertyapplied.

n Complete application of material properties using thelistc contents as input.

n QuitMSC.Patran.

.

Hybrid Microcircuit Materials


HybridMicrocircuit

A B

C D E

Material Conductivity (w/m-C)SiliconSolderAluminaMolybdenumKovar

148.035.730.1139.013.9

Table 1-Material Information

Figure 1-Material Location

(A)(B)(C)(D)(E)

DevicesSubstrate Layers

A B

& Solder



Exercise Procedure:1. Open the existing database


Next, select File from the Menu Bar and select Openfrom the drop-down menu. Select the namemicrocircuit.db from the Database List box.

Select OK to open the database.

MSC.Patran will open a Viewport and change variousMain Form selections from a ghosted appearance to a boldformat.

2. Define the five materials used in this model.

Define a material by selecting the Materials Applicationsradio button. Set the Action, Object, and Method toCreate/Isotropic/Manual Input. Enter the MaterialName Silicon and select Input Properties... to enter thedata. In the Input Options form enter the value provided inTable 1 for Thermal Conductivity. Enter 1.0 for Densityand Specific Heat; these are inert values which are requiredin the form but not used in a steady-state analysis. Thecompleted form should look as follow.


Definematerials

Define materials


Select Apply to define the material.

Without closing the Input Options form edit the MaterialName and repeat the steps for the remaining fourmaterials renaming them appropriately, Solder,Alumina, Molybdenum, and Kovar. Each time enter thecorrect thermal conductivity without changing the densityor the specific heat. Hit Apply with completion of eachmaterial. Select Cancel to close Input Options.

After completing the material definitions deselect theMaterial Application radio button.

Materials

IsotropicManual Input

Filter*Existing Materials

SiliconMaterial NameMaterial

Date: 15-Nov-95Description

Code:Type:

MSC/THERMALThermal

Input Properties...Change Material Status...

Object:Method:

Time: 09:48:33

Input Options

Thermal PropertiesConstitutive Model:

Property Name Value

Time, Temperature or Constant Fields:

-Apply- Clear Cancel

Thermal Conductivity =Density =

[Phase change temperature][Latent Heat] =

Specific Heat = 1.01.0

148.0

Current Constitutive Models:

CreateAction:



3. Divide the geometry and FEM into working groups.

Select Group from the Menu Bar and select Createfrom the drop-down menu. Click in the New Group Namebox and enter hybrid_geom; click in the Group Contents:menu and select Add All Geometry. The completed formis shown below.


Reselect Group/Create, if necessary. Click in the NewGroup Name box enter hybrid_fem click in the GroupContents:menu and select Add All FEM. Turn on UnpostAll Other Groups. Select Apply to complete the function.

From the Menu Bar select Viewing/Named ViewOptions... Select side_view then Close. Select Viewing/Fit View to readjust the display. This is a convenient viewfor creating the next two groups.This can also beaccomplished using the Tool Bar Right Side View icon.

Definegeometryand FEMgroups

Group Create

default_viewportCurrent Viewport

*

Existing Group Names

hybrid_geomNew Group Name

Make Current

Unpost All Other Groups

Add All GeometryGroup Contents:

default_group

Filter

-Apply- Cancel

CreateAction:

Define geometry and FEM groups


Reselect Group/Create, if necessary. Click in the NewGroup Name box enter substrate_fem. Click in theGroupContents:menu and select Add Entity Selection. Turn offMake Current, Posted, and Unpost All Other Groups.From the Select Menu select the Select any FEM entityfilter, third icon from the top; from the next level SelectMenu select the Element filter, also third from the top;finally, in the third level Select Menu select the Hexelement filter, eighth from top. Drag a rectangle around theperimeter of the substrate selecting only the 3 layers ofsubstrate hex elements. The form is shown below.


Repeat these steps dragging a rectangle around onlythe device area and solder to create the last groupnamed device_and_solder.

After all groups are defined, Cancel the Group Function.

Group Create

default_viewportCurrent Viewport

*

Existing Group Names

substrate_femNew Group Name

Make Current

Unpost All Other Groups

Add Entity SelectionGroup Contents:

Elm 425:1480Entity Selection

default_group

Filter

-Apply- Cancel

hybrid_geomhybrid_fem

Posted

CreateAction:



4. Apply the material properties to 4 of the 5 materialregions; intentionally ignore the silicon region.

Select the Properties Applications radio button. Set theAction, Dimension, and Type to Create/3D/Thermal 3DSolid. Enter Property Set Name prop_kovar. Select theInput Properties... box. In the Input Properties form, click inthe Material Name box and select Kovar from theMaterial Properties Sets list. SelectOK to close the form.

Click in the Select Members box. From the at the bottom ofthe screen select the Select a Solid element filter, secondicon from the top, and drag a rectangle around the lowestlayer of hex elements, region E in Figure 1. The completedform is shown below. Select Add then Apply to completethe function.

Repeat these steps for the next three layers of elementsnaming the properties prop_moly, prop_alumina, andprop_solder. Be certain to select the appropriatematerial for each layer. Omit assigning elementproperties to the silicon devices. Refer to Figure 1 formaterial locations.

Applyelementproperties

Element PropertiesCreateAction:3DDimension:

Thermal 3D SolidType:

FE hex, tet, wedgeOption(s):

Existing Property Sets

Property Set Name

Input Properties...

Elm 1129:1480Select Members

Add RemoveApplication Region

Application Region

-Apply-

prop_kovar

Input Properties3D SOLIDProperty Name Value Value Type

OK

[Material orient.-X] Real ScalarMaterial Name Mat Prop Name

[Material orient.-Y] Real Scalar[Material orient.-Z] Real Scalar

Material Property SetsSiliconSolderAluminaMolybdenumKovar

m:Kovar

Using lists to find elements


We are intentionally omitting the application of a materialproperty to some elements. However, it is not unusual inpractice to inadvertently omit assigning an elementproperty to some elements. Use lists to recover them.

5. Identify elements which do not have a materialproperty applied.

Select Tools from the Menu Bar and select List from thedrop-down menu and Create from the submenu. Set theModel, Object, and Method to FEM/Element/Association. In the Association frame scroll to and selectGroup. In the Existing Groups frame select hybrid_fem.Select Apply. All elements will be listed in listacontents:.

Find Target List at the bottom of the Create List form selectB. Set theModel,Object, andMethod to FEM/Element/Attribute. In the Attribute list select Material. In theExisting Materials list drag through all listed materials andselect all materials. Select Apply. Elements with definedmaterials are listed in listb contents:.

The resulting forms are shown below.

Usinglists tofind

Create ListFEMModel:ElementObject:AttributeMethod:

Attribute

AB

Target List

Select

Apply Cancel

uu

Existing Materials

Fringe Value

*

Filter Specification

Filter

Property SetMaterial

SiliconSolder

Kovar

List A`lista` contents:

Add To Group...

Remove From Group...

Highlight ClearPrevious Cancel

Element 37:108 425:1480

List B`listb` contents:

Add To Group...

Remove From Group...

Highlight ClearPrevious Cancel

Element 37:72 425:1480

Create ListFEMModel:ElementObject:

AssociationMethod:

Association

AB

Target List

Surface

Apply Canceluu

Face

Group

u

SolidNode

Existing Materials

*

Filter Specification

Filter

default_groupdevice_femhybrid_femhybrid_geomsubstrate_fem

Alumina

u



Since Lista A contains all elements and List B contains allelements with a material attribute, subtracting List B fromList A will yield List C which will contain all elementswhich do not have material attributes.

Select Tools/List from the Menu Bar and selectBoolean from the submenu. The Boolean List form willoffer several options for Boolean operations, choose the A-B icon. The variable listc now contains the desiredelement list. Select Cancel to exit the Boolean List andselect Cancel again to exit the Create List form. Thecontents of lista, listb, and listc are retained.

MSC.Patran supplies a set of utilities collected under thename Utilities. When installed, Utilities provides a utility,Utilities/Group/Group Elements with No Properties...,which accomplishes the preceding steps in three mouseclicks. We will discuss and use Utilities in later lecturesand exercises.

6. Complete application of material properties usingthe listc contents as input.

To complete element properties return to Create/3D/Thermal 3D Solid. Input the Property Set Nameprop_silicon. Complete the Input Properties form byselecting Silicon from the Material Property Sets. In theSelect Members box type listc (use reverse apostrophes).Notice that listc is evaluated in the Application Region.Select Add then Apply to complete the function.

From the Menu Bar select Viewing/Named ViewOptions... from the drop-down menu. Selectisometric_view then Close. Or use Tool Bar Iso 1 Viewicon.

In the Element Properties form set Action as Show, inExisting Properties selectMaterial Name, and in DisplayMethod select Scalar Plot. Select Groups as hybrid_femand select Apply. The model should now appear as on thefront panel of the exercise.

7. Quit MSC.PatranTo stopMSC.Patran select File on theMenu Bar and selectQuit from the drop-down menu.

Completetheelement

QuitMSC.Patr

Quit MSC.Patran



WORKSHOP 5

Thermal Analysis usingImported CAD Geometry

Objective:n In this exercise you will complete a thermal analysis of a

model created from imported CAD geometry.

WORKSHOP 5 Thermal Analysis using Imported Geometry


Model Description:In this exercise analyze an oven lid clamp. The clamp geometry (incentimeters) will be imported as ProEngineer geometry; from it, create a B-rep solid. Use the Auto TetMeshMesher to mesh the solid. Apply boundaryconditions, complete the analysis and review the results.

This stainless steel (MID 364) clamp is used to clamp the perimeter flangeon a pressurized processing oven lid. The oven lid surface can reach 300oCfor several days. The lid is insulated; the insulation is sometimes pierced bythe clamp edge. The clamp mounting boss is fastened with two bolts andthermal grease (total contact h = 0.01 w/oC-cm2) to a room temperature(20oC) water cooled sink.Determine both that the bracket mounting boss will remain at or below 50oCto ensure safe handling during disassembly and that the spring tab knee andboss transition areas remain at or below 150oC to prevent loss of clampingforce due to creep.

This exercise will introduce a different format for guiding data entry,keystrokes, and mouse operations. Though all actions and entries requiredto accomplish a given step are provided some additional synthesis may berequired by the user since exact images of the entry forms are not provided.

Exercise Overview:n Open a new database named exercise_05.db.

n Import Pro/ENGINEER primitive geometry from a filenamed oventab.geo.

n Create a B-rep solid from these surfaces and delete theoriginal surfaces in the process.

n Mesh the solid with the TetMesh Mesher using Tet4elements, a global edge length of 2.5..

n Define an element property over all the solid elementsusing a material name of 364.

n Create a boundary sink node 999 below the mountingboss and not associated with geometry.

n Change the view for application of boundary conditions

n Apply a 20oC fixed temperature to the sink node.

n Apply a fixed temperature of 300oC to the edge of thesolid in contact with the lid.

Open a new database


n Apply a convection boundary condition of 0.01 w/oC-cm2 to the underside of the mounting boss.

n Select thempidcgs.bin file in the P/Thermal TranslationParameters form in order to select the correct materialproperty units.

n Run the analysis and read the results into the database.

n Fringe plot the temperature results and evaluate themagainst the requirements.

n QuitMSC.Patran.

Exercise Procedure:1. Open a new database named exercise_05.db.

Within your window environment change directories to a convenientworking directory. Run MSC.Patran by typing p3 in your xterm window.

Next, select File from theMenu Bar and select New from the drop-downmenu. Assign the name exercise_05.db to the new database by clicking inthe New Database Name box and entering exercise_05 (.db willautomatically be appended).Select OK to create the new database.

MSC.Patran will open a Viewport and change various Control Panelselections from a ghosted appearance to a bold format. When the New ModelPreferences form appears on your screen, set the Tolerance to Default, andthe Analysis Code toMSC/THERMAL. Select OK to close the New ModelPreferences form.

File

New...New Database Name exercise_05

OK

Tolerance u DefaultAnalysis Code MSC/THERMAL

OK

Open anewdatabase



2. Import Pro/ENGINEER primitive geometry from a file namedoventab.geo.

Select File from the Menu Bar and select Import from the drop-downmenu. Change the Object, Source, and File Type list boxes as shown below.It may be necessary to select a path and use the Filter button to locate theoventab.geo file which should be contained in your home directory.

The model geometry will be imported. A Pro/ENGINEER Model ImportSummary form will provide statistics on the entity type and quantityimported. Click OK to close this form.

The display should appear as shown below.

File

Import...Object ModelSource Pro/ENGINEERFile Type Primitive GeometryPro/ENGINEER Files oventab.geo

Apply

OK

ImportCADgeometry

Import CAD geometry


Select Viewing from the Menu Bar or use the Tool Bar Iso 1 View con tochange to an isometric_view.

Or, use the Tool Bar Iso 1 View Icon.

The model should appear as shown below.

Preference

Graphics...Auto Fit View

ApplyCancelViewingNamed View Options...Select Named View isometric_view

Close

X

Y

Z



3. Create a B-rep solid from these surfaces and delete the originalsurfaces in the process.

Select the Geometry Applications radio button. Create a B-rep solid usingthe following Action, Object, andMethod.

A message window will request confirmation of deletion. Select Yes.

B-rep solid 1 is displayed as white in the viewport.

4. Mesh the solid with the TetMeshMesher using Tet4 elements,a global edge length of 2.5.

Select the Finite Elements Applications radio button. Set the Action,Object, and Type to Create/Mesh/Solid. The Isomesh Mesher is used onregular parametric solids. In order to mesh this B-rep solid use the TetMeshMesher. Use the default Tet4 topology and adjust the Global Edge Lengthand TetMesh Parameters to reduce the mesh resolution for this analysis.

u GeometryCreate/Solid/B-rep

Delete Original Surfaces

Auto Execute

Surface List Apply

Yes

u Finite ElementsCreate/Mesh/SolidGlobal Edge Length 2.5Mesher u TetMeshInput List Apply

Create a B-rep solid

TetMeshthe B-repsolid

Apply element properties to the elements


Your model should appear as shown below.

5. Define an element property over all the solid elements using amaterial MID of 364.

Select the Properties Applications radio button. Set the Action,Dimension,and Type toCreate/3D/Thermal 3D Solid. In the Input Properties form enteran MID of 364 for the Material Name and select Solid 1 as the SelectMember region.

u PropertiesCreate/3D/Thermal 3D SolidProperty Set Name Stainless_steelInput Properties...Material Name 364

OKSelect Members AddApply

X

Y

Z

Applyelementpropertiesto the



6. Create a boundary sink node 999 below the mounting boss andnot associated with geometry.

Select the Finite Elements Applications radio button. Create a boundarynode which is not associated with geometry. The node is numbered 999.Locate the node at [0 -5 0] centered below the mounting boss.

7. Increase node display size and change the view to a Y-Z,side_view. Rotate the view to show the bottom surface of themounting boss.

Increase the display size of nodes to facilitate the application of boundarycondition. Use either Display/Finite Elements... or the associated Tool Baricon to change the node size.

Select Viewing from the Menu Bar to change to a side_view of the model.Alternately, this step can be completed using the Tool Bar Right Side Viewicon.

u Finite ElementsCreate/Node/EditNode ID List 999

Associate with Geometry

Node Location List [0 -5 0]Apply

DisplayFinite Elements...Node Size (use slider bar) 6ApplyCancel

ViewingNamed View Options...Select Named View side_view

Close

Create aboundarysink node

Increasenode sizeandchange to

Increase node size and change to a Y-Z view


Using Viewing/Transformations... from the drop down menu to changethe view point by tilting the 15o around the -Z axis to show the bottomsurface of the mounting boss.

The model should appear as shown below. Note location of Node 999.

ViewingTransformations...

Options...Rotation increment (deg) 15 OK

OK

Node 999



8. Fix the boundary node temperatures at 20.0oC.

Begin applying boundary conditions. Select the Loads/BCs Applicationsradio button. Create a fixed 20.0oC nodal boundary named Sink.

In the Input Data form define the fixed temperature.

In the Select Applications Region form pick node 999.

In order to facilitate applying the next two boundary conditions change thedisplay. SelectDisplay thenEntity Color/Label/Render ...Change RenderStyle to Shaded/Flat or use the Tool Bar Smooth Shaded icon to affect thechange.

u Loads/BCsCreate/Temperature/NodalOption: FixedNew Set Name Sink

Input Data...

Fixed Temperature 20.0

OKSelect Application Region...

u FEMSelect Nodes

Add

OKApply

DisplayEntity Color/Label/Render...Render Style Shaded/Flat

ApplyCancel

Fix nodalboundarytemperature

Fix nodal boundary temperature


The display should appear as shown below. The lower contact edge of thespring tab, and the bottom of the mounting boss should now be visible.

Apply the fixed edge temperature. Enter a New Set Name Edgewith a fixedtemperature of 300.0oC applied to lower edge of the spring tab.

New Set Name Edge

Input Data...Fixed Temperature 300.0

OKSelect Application Region...u GeometrySelect Geometry Entities

Add

OKApply

Bottom of mounting boss

Lower spring tab edge



The display should highlight each node and append the fixed temperature.On some displays the symbol and value may be difficult to discern.

9. Apply contact heat transfer coefficient.

Create the contact heat transfer coefficient boundary conditions with theTemplate, Convection option and the heat transfer coefficient provided,0.01 w/oC-cm2. Name the set contact and apply the boundary condition tothe surface on the bottom of the mounting boss.

In the Input Data form provide the heat transfer coefficient and fluid node.Leave the Template ID field blank.

In the Select Applications Region form select the bottom face of the mountingboss. When selecting the surface the surface chosen will be highlighted. Ifthe incorrect surface is selected simply reselect closer to the centroidallocation of the bottom mounting boss surface. The centroid is locatedbetween the mounting holes and centered on the width of the surface.

u Loads/BCsCreate/Convection/Element UniformOption: Template, ConvectionNew Set Name contact

Target Element Type 3D

Input Data...

Convection Coefficient 0.01Fluid Node ID OKSelect Application Region...

uGeometrySelect Solid Faces Add

OKApply

Applycontactheattransfer

Prepare and run analysis


With boundary conditions applied the model should appear as shown below.

10. Prepare and submit the model for analysis.

Reset the model to an isometric_view. Select Viewing from the Menu Barto change to a isometric_view of the model. Alternately, this step can becompleted using the Tool Bar Iso 1 View icon.

Reset the graphics using the Reset Graphics icon.

Reduce node size using the Node Size icon.

ViewingNamed View Options...Select Named View isometric_view

Close

Prepareand runanalysis



Select theAnalysis Applications radio button to prepare the analysis. Thereare five parameter forms. Change the Translation Parameters... as shownbelow. The analysis will be submitted by selecting Apply in the Analysisform.

11. Read results file and plot results.

From within MSC.Patran the only indication that the analysis hassuccessfully finished is the existence of an nrX.nrf.01 results file in asubdirectory one level below your working directory.

Recall that p3 was initiated from a working directory which contained theexercise_05.db database file. The analysis, initiated from withinMSC.Patran, created a new subdirectory with the same name as the JobName; it should be named exercise_05/. By using Read Result in theAnalysis form and Selecting Results File... you can filter down to the JobName subdirectory and check for the existence of the results file.

u AnalysisAnalyze/Full Model/Full RunTranslation Parameters...File to Extract Undefined Materials: 4, mpidcgs.bin (CGS Units)OKSolution Parameters...Calculation Temperature Scale u CelsiusOKOutput Requests...Units Scale for Output Temperatures u CelsiusOKApply

u AnalysisRead Results/Result EntitiesSelect Results File...Directories /exercise_05

Filter

Read andplot results

Quit MSC.Patran


To plot the results to posted FEM use the Results Application radio button.

Select the Fringe Attributes icon.

The model should now appear as shown on the front panel of this exercise.

What is the maximum reported temperature on the mounting boss? Is it ator below the required maximum of 50oC?

Do the spring tab knee and mounting boss transition temperatures meet therequirement of 150oC?

12. Quit MSC.PatranTo stop MSC.Patran select File on the Menu Bar and select Quit from thedrop-down menu.

Available Files nr0.nrf.01

OKSelect Rslt Template File...Files pthermal_1_nodal.res_tmpl

OKApply

u ResultsCreate/Quick PlotSelect Result Cases TIME: 0.0000000000D+00 S...

Select Fringe Result Temperature,

Display: Element EdgesLabel Style...Label Format: Fixed

Significant figures 4 OKApply

QuitMSC.Patr


WORKSHOP 6

Comparison of Two HeatSink Designs

Objective:n Model two competing finned heat sinks.

n These will be 2D axisymmetric slices.

WORKSHOP 6 Comparison of Two Heat Sink Designs


Model Description:In this exercise you will model a section of a finned heatsink in order tocompare the effect of using different materials.

The model is a representative fin section of a compressor cylinder casing.The maximum total heating on the casing interior has been determined. Achoice of materials is open; the casing can be either aluminum or 1020 steel.Other than cost the only remaining discriminator is temperature; the interiorcasing surface must not exceed 212oF. If both materials keep this surface ator below 212oF steel will be used otherwise aluminum would be thematerial of choice. This analysis will determine the material choice.

Figure 1: Slice Through Compressor Cylinder Casing

R = 2.00 in.

1.0 in. 3.0 in.

0.30 in.

0.30 in.

q/A = 3,400 Btu/hr-ft2 h =2.0 Btu/hr-ft2

Model this section to simplifyboundary conditions

Tambient = 80oF

Materials:

Aluminum: MID = 11020 Steel MID = 353

Open a new database


Exercise Overview:n Create a new database named exercise_06.db. Set Tolerance

to Default, and the Analysis Code toMSC/THERMAL.

n Create the five surfaces which define the heat sink geometry.

n Transform the geometry to create the second heat sink.

n Mesh the surfaces with an IsoMesh.

n Create an ambient node 999.

n Equivalence the nodes at the mating surface edges.

n Apply element properties to the elements using the MIDsprovided. These are 2D Thermal Axisymmetric elements.

n Apply temperature, flux and convection boundary conditions.

n Prepare and submit the model for analysis specifying that it isan Axisymmetric Geometry model, that a units conversion isrequired, and that the direct solver will be used for analysis.

n Read the results file and plot results.

n Check the results against the requirement of 212oF.

n QuitMSC.Patran.



Next, select File from the Top Menu Bar and select New from the drop-down menu. Assign the name exercise_06.db to the new database byclicking in the New Database Name box and entering exercise_06.

Select OK to create the new database.

File

New ...New Database Name exercise_06

OK

Open anewdatabase



MSC.Patran will open a Viewport and change variousMain Form selectionsfrom a ghosted appearance to a bold format. When the New ModelPreferences form appears on your screen, set the Tolerance to Default, andthe Analysis Code toMSC/THERMAL. Select OK to close the New ModelPreferences form.

2. Create the five surfaces which define the model geometry.

Select the Geometry Applications radio button. Create a surface using thefollowing Action, Object, andMethod. Click in the appropriate list boxes toedit the default values and change them to values listed below.

Surface 1 will appear in the viewport. As shown below

Tolerance u DefaultAnalysis Code MSC/THERMAL

OK

u GeometryCreate/Surface/XYZVector Coordinate List Origin Coordinates List [2 0 0]Apply

Create theheat sinksurfaces

Create the heat sink surfaces


Remaining in the Geometry form change the Action, Object, and Method toTransform the existing surface into the required geometry. The TranslationVector entries are easily determined from Figure 1 and are included in theform entries below.

Use Show Label icon to display labels.

Complete the fin by transforming the newly created Surface 2. Note that theRepeat Count is adjusted to 3 to create the full fin length.

u GeometryTransform/Surface/Trans-lateTranslation Vector

Auto Execute

Surface List Apply

u GeometryTransform/Surface/Trans-lateTranslation Vector Repeat Count 3Surface List Apply



The resulting model is shown below.

3. Transform the geometry to create the second heat sink.

Duplicate the entire heat sink cross section by transforming all the existingsurfaces. Note that the Repeat Count is adjusted back to 1 to create the asingle copy of the heat sink. The completed geometry is shown below.

u GeometryTransform/Surface/Trans-lateTranslation Vector Repeat Count 1Surface List Apply

X

Y

Z

1

2 3

4

5 6 7

8

9

10

11

121

2 3 4 5

Create thesecondheatsink

IsoMesh the surfaces


The display should now appear as shown below.

4. Mesh the surfaces with an IsoMesh.

Select the Finite Elements Applications radio button. Set the Action,Object, and Type toCreate/Mesh/Surface. Accept the Global Edge Lengthof 0.1 and select all surfaces for inclusion in the Surface List.

Use Hide Label Icons to turn off all labels.

u Finite ElementsCreate/Mesh/SurfaceSurface List

Apply

X

Y

Z

12 3

4

5 6 78

910

1112

1314 15

16

17 18 1920

2122

2324

12 3 4 5

67 8 9 10

IsoMeshthesurfaces




5. Create an ambient node 999.

Using the Finite Elements form create a boundary node which is notassociated with geometry. The node is numbered 999. Locate the node at[6.2 0.9 0] to the right of and between the two models.



Node Location List [6.2 0.9 0]Apply

X

Y

Z

Create anambientnode

Equivalence nodes


Increase the display size of nodes to facilitate the application of boundarycondition. Use either Display/Finite Elements... or the associated Tool BarNode Size icon to change the node size. The model should now appear asshown below.

6. Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action/Object/Method toEquivalence/All/Tolerance Cube and select Apply to eliminate duplicatenodes created at geometric entity edges.

7. Apply element properties to the elements using thetwo material properties MIDs, 1 and 353.

DisplayFinite Elements...Node Size 6

ApplyCancel

u Finite ElementsEquivalence/All/Tolerance CubeApply

X

Y

Z

Equivalence nodes

Applyelementproperties



In a typical modelling sequence the Materials Application radio buttonwould be the next stop to define a material for application in ElementProperties. However, MSC.Thermal includes a Material PropertiesDatabase which contains 970 materials with thermal properties alreadydefined. Use this database to facilitate the analysis.

Select the PropertiesApplications radio button. Set the Action, Dimension,and Method to Create/2D/Thermal Axisymmetric. Enter Property SetName Steel. Select the Input Properties... box. In the Input Properties form,click in the Material Name box and enter 353. Select OK to close theform.Click in the Select Members box and drag a rectangle around the lowermodel in the viewport. SelectAdd thenApply in the Element Properties formto complete the element property definition.

Perform the same steps for upper model using, Aluminum, for theProperty Set Name, and 1 for theMaterial Name.

8. Apply the temperature, convection, and fluxboundary conditions to the model.

Begin applying boundary conditions. Select the Loads/BCs Applicationsradio button. Create a fixed 80.0oF nodal boundary named Ambient In theInput Data form define the fixed temperature. In the Select Applications Regionform pick node 999.

u PropertiesCreate/2D/Thermal AxisymmetricProperty Set Name Steel

Input Properties...Material Name 353

OKSelect Members

Add

Apply

u Loads/BCsCreate/Temperature/NodalOption: Fixed

Applyboundaryconditions

Apply boundary conditions


Create the heat transfer coefficient boundary conditions with the Template,Convection option, set name Air, and a heat transfer coefficient of 2.0 Btu/oF-hr-ft2. Apply the boundary condition to the exposed edges of bothfinned heat sinks as shown in Figure1. The same boundary condition isapplied to both heat sink models.

In the Input Data form provide the heat transfer coefficient and fluid node.

New Set Name Ambient

Input Data...Fixed Temperature 80.0

OKSelect Application Region...Geometry Filter u FEMSelect Nodes Add

OKApply

u Loads/BCsCreate/Convection/Element UniformOption: Template, ConvectionNew Set Name AirTarget Element Type 2D

Input Data...

Convection Coefficient 2.0Fluid Node ID OKSelect Application Region...



In the Select Applications Region form select the right facing and bottomfacing exposed edges of the finned heat sinks. Switch to the Select an Edgeicon in the Select Menu form.When selecting the edges the edge chosen willbe highlighted. Hold down the key and use the left mouse button tocollect all the edges in the Select Surfaces or Edges box.

Create a set name Flux of 3400 Btu/hr-ft2. Apply the boundary conditionto the left facing edges of both finned heat sinks as shown in Figure1. Thesame boundary condition is applied to both heat sink models.

In the Select Applications Region form select the left facing exposed edges ofthe finned heat sinks. Switch to the Select an Edge icon, if necessary, in theSelect Menu form. When selecting the edges the edge chosen will behighlighted. Hold down the key and use the left mouse button tocollect all the edges in the Select Surfaces or Edges box.

Geometry Filter uGeometrySelect Menu Select an Edge icon

Select Surfaces or Edges

Add

OKApply

u Loads/BCsCreate/Heating/Element UniformOption: Flux, FixedNew Set Name FluxTarget Element Type 2D

Input Data...Heat Flux 3400

OK

Select Application Region...

Prepare and run analysis


With boundary conditions applied the model should appear as shown below

9. Prepare and submit the model for analysis.

Select theAnalysis Applications radio button to prepare the analysis. Selectthe parameter forms reviewing and changing the settings as shown below.The analysis is submitted by selecting Apply in the Analysis form.

Geometry Filter uGeometrySelect Menu Select an Edge icon

Select Surfaces or Edges

Add

OKApply

u Analysis

X

Y

Z

2.000

2.000

2.000 2.000

2.000

2.000

2.000 2.000

2.000

2.000

2.000 2.000

2.000

2.000

2.000 2.000 99980.00

3400.

3400.

3400.

3400.

3400.

3400.

Prepareand runanalysis



Analyze/Full Model/Full RunTranslation Parameters...Model Dimensionality u Axisymmetric Geometry, R Z

Co-ordinates

Radial, R Co-ordinate u X axisCenterline, Z Co-ordinate u Y axis

Perform Geometry UnitsConversion

From Units inchesTo Units feetFile to Extract Undefined Materials: 3,mpidfph.bin (Btu-feet-lbm..OKSolution Parameters...Calculation Temperature Scale u FahrenheitSolver Option 2, Direct SolverRun Control Parameters...Initial Temperature 212.0Initial Temperature Scale u FahrenheitOKOKOutput Requests...Units Scale for Output Temperatures u FahrenheitUnits Definition for Time Label Hours

OKSubmit Options...OKApply

Read and plot results


While waiting for the analysis to finish. Reset Graphics and reduce nodesize.

10. Read results file and plot results.

From within MSC.Patran the only indication that the analysis hassuccessfully finished is the existence of an nrX.nrf.01 results file in asubdirectory one level below your working directory.

P3 was initiated from a working directory which contained theexercise_06.db database. The analysis created a new subdirectory with thesame name as the Job Name; exercise_06/. By using Read Result in theAnalysis form and Selecting Results File... you can filter down to the JobName subdirectory and check for the existence of a results file.

To plot the results to posted FEM use the Results Application radio button.

u AnalysisRead Results/Result EntitiesSelect Results File...Directories /exercise_06

FilterAvailable Files nr0.nrf.01

OKSelect Rslt Template File...Files pthermal_1_nodal.res_tmpl

OKApply

u ResultsCreate/Quick PlotSelect Result Cases TIME: 0.0000000000D+00 S...

Select Fringe Result Temperature,

Read andplot results



Select the Fringe Attributes icon.

The model should now appear as shown on the front panel of this exercise.

Which material will be chosen for the cylinder casing?

11. QuitMSC.PatranTo stop MSC.Patran select File on the Top Menu Bar and select Quit fromthe drop-down menu.

Display: Element EdgesLabel Style...Label Format: Fixed

Significant figures 4 OKApply

QuitMSC.Patr

Quit MSC.Patran



WORKSHOP 7

An Oven Window Design

Objective:n Model a 2D planar slice of an oven window.

n Learn how to initiate and use Utilities.

WORKSHOP 7 An Oven Window Design


Model Description:In this exercise you will model a 2D planar section of an oven window. Youwill learn how to initiate and use Utilitieswhich facilitate this task.

A manufacturer of appliances is proposing a self cleaning oven design thatuses a composite window separating the oven cavity from room air. Thecomposite consists of two high temperature plastics (A &B) whose physicaland thermal attributes are shown below. The combined convection/linearized radiation heat transfer parameters for inside and outside of theoven are also shown. (Note: Radiation will be linearized and is include inthe heat transfer coefficient). The design specification for safe operationrequires an outside oven temperature of 50C or less.

The following assumptions can be made for the model:

n Steady-state conditions exist.

n The oven door can be modeled as a 2-dimensional slice.

n Contact resistance is negligible.

n Each plastic is homogeneous with constant properties.

Air

Air

Composite Window

T= 24o C

hambient = 13 W/m2C

Oven CavityToven = 345o Choven = 16 W/m2C

Ambient

0.2 m

LA

Trequired 50C

A B

kA = 0.13 W/mC

kB = 0.07 W/mC

LA = 0.050 m

LB = 0.030 m

LB

Figure 1


Information on Utilities:Utilities refer to a set of tools which facilitate the use of MSC.Patran. Thesetools are supplied with MSC.Patran. In version 9.0 they are located on eachCD ROM.

Utilities are written or supplied by MSC.Software software developers,applications engineers, and anyone within MSC who has a good idea forimproving MSC.Patran functionality. Sometimes Utilities are the vehiclefor implementing an improvement which for organizational reasons will notbe officially implemented within a reasonable release horizon.

Utilities are written in PCL, MSC.Patran Command Language. SinceUtilities are developed from the personal initiative of individuals and not aspart of theMSC.Software corporate software development strategy, they arenot subjected to any formal quality assurance testing. Hence, they aresupplied by MSC.Software as a courtesy but they are officially notsupported by MSC.Software. Most Utilities are supplied with the authorsname, an e-mail address, and telephone number. If you have a problem witha Utilities tool you may contact the author if ownership data is available.You may report suspected or identified problems with Utilities to theMSC.Patran support line but no obligation to fix the Utilities problem isincurred by MSC.Software. That being said, Utilities are generally reliableand quite handy. Most intermediate and advanced user of MSC/PATRANinstall and use Utilities.

Load the MSC.Patran CD in the CD-ROM drive and mount the CD-ROMdrive Installation instructions are listed in Installing PCL Utilities andMSC.Software Institute Files on Unix, p. 43 of MSC.Patran Installationand Operations Guide. Instructions for Windows NT are found on p. 65.

If the user has installed MSC.Patran with the FULL install option utilitiesare loaded automatically. If user selects CUSTOM installation, then PCLUtilities must be selected as an option under the MSC.Patran CoreApplications.

When loaded (installed) Utilities are initiated by copying the p3epilog.pclfile from /shareware/msc/unsupported/utilities (e.g.,/patran/patran3/shareware/msc/unsupported/utilities/p3epilog.pcl), into ausers home directory (for user-by-user access) or the P3_HOME directory(for a system wide access). Once the p3epilog.pcl file is in place Utilities isavailable as a pick on the Menu Bar after re-starting MSC.Patran.



Exercise Overview:n Create a new database named exercise_07.db. Set

Approximate Maximum Model Dimension to 0.20, and theAnalysis Code toMSC/THERMAL.

n Create two surfaces which define the oven window geometry.

n Mesh the surfaces with an IsoMesh, Global Edge Length of0.003.

n Create two fluid nodes 9998 and 9999 for the oven interior andambient conditions respectively.

n Equivalence the nodes at the mating surface edges.

n Define the two material properties for the plastics.

n Apply element properties to the elements using the definedmaterials. These are Thermal 2D elements.

n Use the Fields Form to define the temperature distribution atthe interior pane upper edge.

n Apply temperature and convection boundary conditions.

n Visualize and verify the convection LBCs using Utilities/Thermal/Thermal BC Display...

n Prepare and submit the model for analysis specifying that it isa 2D Plane Geometry model and that theWeakly NonlinearSolution solver will be used for analysis.

n Read the results file and plot results.

n Check the results against the requirement of 50oC.

n QuitMSC.Patran.

Open a new database




Next, select File from theMenu Bar and select New from the drop-downmenu. Assign the name exercise_07.db to the new database by clicking inthe New Database Name box and entering exercise_07.

Select OK to create the new database.

MSC.Patran will open a Viewport and change variousMain Form selectionsfrom a ghosted appearance to a bold format. When the New ModelPreferences form appears on your screen, set the Approximate MaximumModel Dimension to 0.20, and the Analysis Code to MSC/THERMAL.Select OK to close the New Model Preferences form.

2. Create two surfaces which define the oven window geometry.

Select the Geometry Applications radio button. Create a surface using thefollowing Action, Object, andMethod. Click in the appropriate list boxes toedit the default values and change them to values listed below.

File

New ...New Database Name exercise_07

OK

Approximate Maximum Model Dimen-sion:

0.20

Analysis Code MSC/THERMAL

OK

u GeometryCreate/Surface/XYZVector Coordinate List

Apply

Open anewdatabase

Create theovenwindow



Turn on labels using the Show Labels icon.

Create the second surface from the same Action/Object/Method but changethe Vector Coordinate List to . Modify theOrigin CoordinatesList by clicking in the list box and selecting Point 4 from the viewport.

The model will appear as shown below.

u GeometryCreate/Surface/XYZ

Auto Execute

Vector Coordinate List Origin Coordinates List Apply

IsoMesh the surfaces


3. Mesh surfaces with an IsoMesh, global edge length of 0.003.

Select the Finite Elements Applications radio button. Set the Action,Object, and Type toCreate/Mesh/Surface. Change theGlobal Edge Lengthto 0.003 and select both surfaces for inclusion in the Surface List.

Turn off labels using Hide Labels icon.

4. Create two fluid nodes 9998 and 9999 for the oven interior andambient conditions respectively.

Using the Finite Elements form create a boundary nodes which are notassociated with geometry. The node numbers are 9998 and 9999. Locate thenodes at [-0.03 0 0] and [0.11 0 0], to the left and right of model.The spatial location of the boundary nodes is irrelevant to the analysis; but,these locations facilitate display and verification of LBCs.

u Finite ElementsCreate/Mesh/SurfaceGlobal Edge Length 0.003Surface List

Apply



Node Location List [ -0.03 0 0]ApplyNode Location List [0.11 0 0]Apply

IsoMeshthesurfaces

Create anambientnode



Increase the display size of nodes to facilitate the application of boundarycondition. Use either Display/Finite Elements or the associated ToolbarNode Size icon to change the node size. The model should now appear asshown below.


DisplayFinite Elements...Node Size 6

ApplyCancelor,

Equivalence nodes


5. Equivalence the nodes at the mating surface edges.

Using the Finite Elements form set the Action, Object, and Method toEquivalence/All/Tolerance Cube and select Apply to eliminate duplicatenodes created at geometric entity edges.

6. Define the two material properties for the plastics.

Since this will be a steady state analysis, thermal conductivity is the onlymaterial property used in the solution. Thermal conductivity values areprovided in Figure 1; however, the Input Options form also requires data forDensity and Specific Heat. Enter a value of 1.0 in each of these fields.The Apply button is selected from within the Input Options form. The formdoes not close upon hitting Apply. This is a convenient, if unintended,feature since one needs only to enter a new material name inMaterial Nameand proceed with entering new material data in the Input Options form.

After each Apply the new material should appear in the Existing Materialslist box on the Materials form.

u Finite ElementsEquivalence/All/Tolerance CubeApply

u MaterialsCreate/Isotropic/Manual InputMaterial Name ka

Input Properties...Thermal Conductivity = 0.130Density = 1.0Specific Heat = 1.0

OKApplyMaterial Name kbThermal Conductivity = 0.07Density = 1.0Specific Heat = 1.0

Equivalence nodes

Define twomaterials



7. Apply element properties to the elements using thedefined materials. These are Thermal 2D elements.

Select the Properties Applications radio button. Set the Action,Dimension,and Type to Create/2D/Thermal 2D. Enter Property Set Nameinterior_pane. Select the Input Properties... box. Click in the MaterialName box and select ka from theMaterial Property Sets list box. SelectOKto close the form.Click

Introduction to Thermal Analysis Using MSC.thermal

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