ws8c-1 workshop 8c tension coupon nas120, workshop 8c, november 2003

WS8C-1

WORKSHOP 8C

TENSION COUPON

NAS120, Workshop 8C, November 2003

WS8C-2NAS120, Workshop 8C, November 2003


Problem Description A tension coupon is constructed from aluminum with E = 10 x 106 psi

and = 0.3

The coupon thickness is 0.125 in

An edge load of 50 lb is applied to the tension coupon


50 lb

10 in

4 in

2.0 DIA Hole


Workshop Objectives Build the tension coupon geometry

Control the mesh by using techniques discussed in class

Compare FEA stress results to theoretical results

From “Stress Concentration Factors” by R. E. Peterson, Figure 86:

max = 432 psi


Suggested Exercise Steps1. Create a new database.

2. Create a geometry model of the tension coupon.

3. Use Mesh Seeds to define the mesh density.

4. Create a finite element mesh.

5. Verify the finite element mesh.

6. Define material properties.

7. Define element properties and apply them to the model.

8. Apply boundary conditions to the model.

9. Apply loads to the model.

10. Submit the model to MSC.Nastran for analysis.

11. Post Process results using MSC.Patran.


a

b c

d

e

f

g

Step 1. Create New Database

Create a new database called tension_coupon.db

a. File / New.

b. Enter tension_coupon_c as the file name.

c. Click OK.

d. Choose Default Tolerance.

e. Select MSC.Nastran as the Analysis Code.

f. Select Structural as the Analysis Type.

g. Click OK.

a


Step 2. Create Geometry

Create two arcs

a. Geometry: Create / Curve / 2D ArcAngles.

b. Enter 0 for the Start Angle.

c. Enter 45 for the End Angle.

d. Enter [5 2 0] for the Center Point List.

e. Click Apply.

f. Repeat the procedure with 45 as the Start Angle and 90 as the End Angle.

a

b

c

d

e



Create two more curves.

a. Geometry: Create / Curve / XYZ.

b. Enter <0 2 0> for the Vector Coordinates List.

c. Enter [7 2 0] for the Origin Coordinates List.

d. Click Apply.

e. Repeat the procedure using <2 0 0> as the vector and [5 4 0] as the origin.

a

b

c

d



Create two surfaces

a. Geometry: Create / Surface / Curve.

b. Screen pick the top curve as shown.

c. Screen pick the upper arc.

d. Screen pick the right curve as shown.

e. Screen pick the lower arc.

f. Turn on display lines.

ab

c

e

d

f



Create an extruded surface

a. Geometry: Create / Surface / Extrude.

b. Enter <3 0 0> as the Translation Vector.

c. Click in the Curve List box, then screen pick the right curve as shown.

a

c b



Mirror the surfaces

a. Geometry: Transform / Surface / Mirror.

b. Set the Mirror Plane Normal to Coord 0.2.

c. For the Offset enter 2.

d. Click in the Surface List box.

e. Rectangular select all the surfaces as shown.

a

c

b

e

d



Mirror the surfaces again

a. Geometry: Transform / Surface / Mirror.

b. Set the Mirror Plane Normal to Coord 0.1.

c. For the Offset enter 5.

d. Click in the Surface List box.

e. Rectangular select all the surfaces as shown.

a

b

ce

d



The mirrored surfaces should look like the picture on the right.

a. Turn off display lines

a


Step 3. Create Mesh Seeds

Create a uniform mesh seed

a. Elements: Create / Mesh Seed / Uniform.

b. Enter 3 for the Number of Elements.

c. Click in the Curve List box.

d. Screen pick each of the four edges on the left and right sides of the circle as shown.

a

b

c

d



a

b

c

d

Create a biased mesh seed

a. Elements: Create / Mesh Seed / One Way Bias.


c. Enter 4 for L2/L1.

d. Click on the Curve List box.

e. Screen pick three of the remaining edges on the circle as shown. e



Create a biased mesh seed

a. Elements: Create / Mesh Seed / One Way Bias.


c. Enter 0.25 (or -4) for L2/L1.

d. Click on the Curve List box.

e. Screen pick the 1 remaining edge on the circle.

f. Screen pick the horizontal edge to the right of the circle.

a

b

c

d

e

f


The mesh seeds should agree with the picture on the right.



Step 4. Create Mesh

Create a finite element mesh

a. Elements: Create / Mesh / Surface.

b. Set the Element Shape to Quad, Mesher to IsoMesh, and Topology to Quad4.

c. Click in the Surface List box.

d. Rectangular pick the surfaces as shown.

e. Enter 0.5 as the value for Global Edge Length.

f. Click Apply.

a

b

c

f

e

d


Step 4. Create Mesh

Equivalence the model

a. Elements: Equivalence / All / Tolerance Cube.

b. Click Apply.a

b


Step 5. Verify Mesh

Verify the quality of the finite elements

a. Elements: Verify / Quad / All.

b. Click Apply.

c. Review the summary table.

a

b

c


Step 5. Verify Mesh

Perform specific quality tests on the elements.

a. Elements: Verify / Quad / Aspect.

b. Click Apply.

c. Review the fringe plot.

d. Repeat for Warp, Skew, and Taper tests.

e. Reset Graphics.

a

b

c

d

e


Step 5. Create Material Properties

Create an isotropic material

a. Materials: Create / Isotropic / Manual Input.

b. Enter aluminum as the Material Name.

c. Click Input Properties.

d. Enter 10e6 for the elastic modulus and 0.3 for the Poisson Ratio.

e. Click OK.

f. Click Apply.

a

b

c

d

fe


Step 6. Create Element Properties

Create element properties

a. Properties: Create / 2D / Shell.

b. Enter plate as the Property Set Name.

c. Click Input Properties.

d. Click on the Select Material Icon.

e. Select aluminum as the material.

f. Enter 0.125 for the thickness.

g. Click OK.

a

b

c

d

f

g

e


Step 6. Create Element Properties

Select application region

a. Click in the Select Members box.

b. Rectangular pick the surfaces as shown.

c. Click Add.

d. Click Apply.

ac

d

b


Step 7. Apply Boundary Conditions

Create the boundary condition

a. Loads/BCs: Create / Displacement / Nodal.

b. Enter fixed as the New Set Name.

c. Click Input Data.

d. Enter <0 0 0> for Translations and <0 0 0> for Rotations.

e. Click OK.

a

b

d

e

c



Apply the boundary condition

a. Click Select Application Region.

b. Select the Curve or Edge filter.

c. Select the bottom left edge of the surface.

d. Click Add.

e. Select the top left edge of the surface.

f. Click Add.

g. Click OK.

h. Click Apply.

ag

h

b

c

e

d f



The boundary condition should agree with what’s shown on the right


Step 8. Apply Loads

Create the load

a. Loads/BCs: Create / Total Load / Element Uniform.

b. Enter force as the New Set Name.

c. Set the Target Element Type to 2D.

d. Click Input Data.

e. Enter <50 0 0> for the Edge Load.

f. Click OK.

d

b

c

a

e

f


Apply the load

a. Click Select Application Region.

b. For the application region select the right edge of the top right surface as shown.

c. Click Add.

d. Select the right edge of the bottom right surface.

e. Click Add.

f. Click OK.

g. Click Apply.

Step 8. Apply Loads

a

b

c

f

g

ed


Step 8. Apply Loads

The loads and boundary condition should agree with what’s shown on the right.


Step 9. Run Linear Static Analysis

Analyze the model

a. Analysis: Analyze / Entire Model / Full Run.

b. Click Solution Type.

c. Choose Linear Static.

d. Click OK.

e. Click Apply.

a

e

b

d

c


Step 10. Post Process with MSC.Patran

Attach the results file

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

b. Click Select Results File.

c. Choose the results file tension_coupon_c.xdb.

d. Click OK.

e. Click Apply.

a

b

c

e

d



Erase geometry

a. Display: Plot/Erase.

b. Under Geometry click Erase.

c. Click OK.

a

b

c



Create a Quick Plot of X Component Stress

a. Results: Create / Quick Plot.

b. Select Stress Tensor as the Fringe Result.

c. Select X Component as the Fringe Result Quantity.

d. Click Apply.

e. Record the maximum X component stress.

Max X Stress = ________

a

b

c

d



Turn off averaging

a. Results: Create / Fringe.

b. Select Stress Tensor as the Fringe Result.

c. Select X Component as the result quantity.

d. Click on the Plot Options Icon.

e. Change the Coordinate Transformation to CID.

f. Select Coordinate 0.

g. Change the Averaging Definition Domain to None.

h. Click Apply.

a

b

c

d

g

h

f

e

ws8c-1 workshop 8c tension coupon nas120, workshop 8c, november 2003

Documents