MSC StudentenwettbewerbWintersemester 2012/13

Nastran - Patran

Aufgabe

Software Version

Patran 2011

MSC/MD Nastran 2011

Files Required

strut.xmt

Wie groß ist die maximale Verschiebung ?

3

TUTORIAL

Problem Description– A landing gear strut has been designed for a new fighter jet. Determine

if the landing gear strut has been designed properly to withstand the landing load.

– E = 30 x 106 psi � ν =0.3– Landing Load = 7,080 lb

Suggested Exercise Steps 1. Create a new database and name it strut.db2. Import the strut geometry from strut.xmt3. Mesh the strut to create solid elements with global edge length = 0.5

Use Tet4 Elements instead of Tet10 (Limitation in N odes)1. Fix the cylindrical hole at the bottom of the strut2. Apply a total load of 7080 lb in the negative Y direction to the circular

surface at the top of the strut3. Create an isotropic material with elastic modulus = 30e6 and Poisson's

ratio = 0.34. Create a physical property, applying your isotropic material to the entire

solid5. Run a linear static analysis.6. Attach the results.7. Plot the Von Mises stress on the deformed shape.

Step 1. Create New Database

Create a new database called strut.db:a. Under the Home tab, click New

in the Defaults group.b. Enter strut as the file name.c. Click OK.d. Select Based on Model for

Tolerance.e. Select MSC.Nastran as the

Analysis Code.f. Select Structural as the

Analysis Type. g. Click OK.

a

b c

d

fg

e

Step 2. Import Geometry

Import the parasolid file:a.File : Import… .b.Select the file strut.xmt .c.Click Apply .d.Click OK.

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d

b c

f

b

cd

e

a

Step 3. Mesh the Solid

Create a solid mesh:a. Under the Meshing tab,

click Solid in the Meshersgroup.

b. Select the solid, Solid 1 .c. Deselect Automatic

Calculation under Global Edge Length.

d. Enter 0.5 for the Global Edge Length Value .

e. Click Apply .f. Under the Home tab, click

the Iso2 View icon in the Orientation group.

Tet4

Step 4. Apply Boundary Conditions

Create a fixed boundary condition:a.Under the Loads/BCs tab, click Displacement Constraint in the Nodal group.b.Enter hub cylinder as the New Set Name.c.Click on Input Data .d.Enter <0 0 0> for Translations. e.Click OK.

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c

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a

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f

d

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Step 4. Apply Boundary Conditions (Cont.)

Apply the boundary condition:a.Click on Select Application Region .b.For Geometry Filter, select Geometry .c.Set the Selection Filter to Surface or Face and select the cylinder at the bottom of the strut, as shown.d.Click Add .e.Click OK. f.Click Apply .

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d

e

a

f

c

d

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Step 5. Apply Loads

Create a load:a. Click Total Load in the Element

Uniform group.b. Enter landing load as the New

Set Name.c. Click on Input Data .d. Enter <0 -7080 0> for Load. e. Click OK.

b

a

c

e

d

b

c

Step 5. Apply Loads (Cont.)

Apply the load:a.Click on Select Application Region .b.For the Geometry Filter, select Geometry .c.Select the upper circular surface at the top of the strut, as shown.d.Click Add .e.Click OK. f.Click Apply .

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f

d

f

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c

g

Step 6. Create Material Properties

Create an isotropic material:a.Under the Properties tab click Isotropic in the Isotropic group.b.Enter steel for the Material Name.c.Click on Input Properties .d.Enter 30e6 for the Elastic Modulus.e.Enter 0.3 for the Poisson Ratio.f.Click OK. g.Click Apply .

a

a

b

ce

Step 7. Create Physical Properties

Create physical properties:a.Click Solid in the 3D Properties group.b.Enter strut as the Property Set Name.c.Click on Input Properties .d.Select steel as the material.e.Click OK.

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c

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b

a

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Step 7. Create Physical Properties (Cont.)

Apply the physical properties:a.Click on Select Application Region .b.Select the solid.c.Click Add .d.Click OKe.Click Apply .

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d

e

b

Step 8. Run Linear Static Analysis

Analyze the model:a.Under the Analysis tab click Entire Model in the Analyze group.b.Click on Solution Type .c.Select Linear Static as the Solution Type.d.Click OK.e.Click Apply .

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a

b

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Step 9. Attach the Results

Attach the results file:a.Click XDB in the Access Results group.b.Click on Select Results File .c.Select the results file, strut.xdb .d.Click OK. e.Click Apply .

c

d

Step 10. Plot Stress and Displacement

Create a quick plot:a.Under the Results tab, clickFringe/Deformation in the Quick Plot group.b.Select Stress Tensor as theFringe Result.c.Select Displacements, Translational as the Deformation Result.d.Click Apply .e.Right-click in the viewport andselect Model Orientation > Isometric > Iso1 View from thecontext menu.

This completes the workshop.

a

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d

c

b

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19

Die Lösung bitte bis zum

31. März 2013 an

university.de@mscsoftware.com