14 anchor analy pat301

WS15-1PAT301, Workshop 15, December 2005Copyright© 2005 MSC.Software Corporation

WORKSHOP 15ANCHOR ANALYSIS


Workshop ObjectivesPerform a linear static MSC.Nastran analysis. Display structuraldeformation and element stress. Use several display attributes.

Problem DescriptionDeformation: wireframe for render, show with undeformed or notElement stress: stress tensor, von Mises, element edge, target entities, inter-element averaging or none, derive/average, intra element shape fn. or average

Software VersionMSC.Patran 2005r2MSC.Nastran 2005r2b


Key Concepts and Steps:Database: open existing MSC.Patran database Anchor.dbAnalysis: Solution Type = Nastran Linear Static, Solution Sequence = 101, Method = Full RunAnalysis: access analysis results by attaching the XDB file to databaseDeformation:

Plot displacement results using defaultsPlot displacement results w/o undeformed shape and no geometry

Element stress:Plot von Mises stress, and show element edgesPlot von Mises stress, show element edges, and use a subset of elementsZoom into a select area to view the stressRepeat, and use no inter-element averaging (None), Derive/Average, and use Shape Fn. for intra-elementRepeat, and use inter-element averaging (All Entities), Derive/Average, and use Average for intra-element


Step 1: Open Database

Open existing database Anchor.db

a. File/Open.b. Select Anchor.db.c. Click OK.

a

b

c


Step 2: Check Load Case

Check the load casea. Click on the Smooth

shaded icon.b. Load Case : Modifyc. Select Default for Select

Load Case to Modify.d. Check to see that the

correct Loads/BCs have been assigned.

e. Click Cancel.

b

c

d

e

a


Step 3: Set-up for the Analysis

Set-up for the analysis.a. Analysis : Analyze / Entire

Model / Full Run.b. Click Translation

Parameters…c. Select XDB and Print for

Data Output.d. Click OK.e. Click Solution Type.f. Select Linear Static for

Solution Type.g. Click OK.h. Click Apply.

a

b

c

d

e

f

gh


Step 3: Set-up for the Analysis (Cont.)

Set-up for the Analysisa. Click Subcases…b. Select Default for

Available Subcases. Default should be selected automatically for Available Load Cases.

c. Click Apply d. Click Cancel.e. Click Subcase Select to

see that Default is selected under Subcases Selected.

f. Click OK.g. Click Apply to run

MSC.Nastran.a

b

c d

f

eg

e


Step 4: Make MSC.Nastran Results Accessible to MSC.Patran

Make MSC.Nastran results accessible to MSC.Patran.

a. Analysis: Access Results / Attach XDB / Result Entities.

b. Click Select Results File…

c. Select Anchor.xdb.d. Click OK.e. Click Apply.

a

b

c

d

e


Step 5: View the Deformation

View the deformation results under Results.

a. Result: Create/Deformation.

b. Select SC1 DEFAULT…for Select Result Case(s).

c. Select Displacements, Translational for Select Deformation Result.

d. Click Apply.

a

b

c

d


Step 6: View Only the Deformed Shape

View only the deformed shape.a. Click Display Attributes. b. Select Wireframe for

Render Style.c. Deselect Show

Undeformed.d. Click Plot/Erase Icon.e. Click Erase for Geometry.f. Click OK.g. Click Apply.

This display will produce the deformed shape without both the model geometry and undeformed finite element model.

a

b

c

d

e

g

f


Step 7: View the von Mises Stress

View the Von Mises stress results shown on the deformed shape.

a. Results: Create/ Fringe.b. Select SC1:DEFAULT,

A1:Static Subcase under Select Result Case(s).

c. Select Stress Tensor for Select Fringe Result.

d. Under Quantity select von Mises.

e. Click Display AttributesIcon.

f. Select Element Edgesfor Display.

g. Click Apply.

f

g

a

c

eb

d


Step 8: Show a Fringe Plot for a Subset of Elements

Show a fringe plot for a subset of the elements.

a. Click Target EntitiesIcon.

b. Select Elements for Target Entity.

c. See Figure for Select Elements.

d. Click Apply.

ab

c

d

c


Step 9: Zoom to Higher Stressed Region

Zoom in to see if there are sufficient tet10 elements to represent the stress gradient.

a. Click View Corner Icon.b. See Figure to select the

region. c. Use Mouse Rotate XY

Icon to see the stress more clearly.

a

b

c

c


Change how the Von Mises stress is shown on the elements under Plot Options/ Averaging Definition.

a. Click on Iso 3 view, then Fit view icon.

b. Results: Create / Fringe.c. Select Plot Options Icon.d. Select None for Domain.e. Select Derive/Average for

Method.f. For Intra-element (within an

element) select Shape Fn. for Extrapolation.

g. Select the Target Entitiesicon and set the entity to Current Viewport.

h. Click Apply.

Step 10: Use Inter-element Averaging for von Mises Stress

b

c

def

h

a

g

The results are different, but do not differ greatly


Step 11: Use Average Extrapolation Within Each Element

Use average extrapolation to see the difference.

a. Results: Create/Fringe.b. Select Plot Options.c. Select All Entities for Averaging

Definition, Domain.d. Select Derive/Average for Method.e. Select Average for Extrapolation

(intra-element).f. Click Apply.

Under Extrapolation see how using Average (Patran averages results within each element and uses them at the respective element nodes) produces different results from using the default setting Shape Fn. (the shape function for each element is used to determine results at the respective element nodes)

cde

a

f

b


Step 12: Quit MSC.Patran

Quit MSC.Patrana. Select File on the Menu Bar

and select Quit from the drop down menu

a

14 anchor analy pat301

Documents