workshop 13 cantilevered beam using 1d or 2d … · pat301, workshop 13, december 2005...

WS13-1PAT301, Workshop 13, December 2005Copyright© 2005 MSC.Software Corporation

WORKSHOP 13CANTILEVERED BEAM USING 1D OR

2D ELEMENTS, AND ANALYSIS


Workshop ObjectivesCreate two models of a cantilevered beam. The models are for 1D (bar elements) or 2D (plate elements). Compare the results from the analysis for the models.

Problem DescriptionCompare the deformation and stress results for the two types of models.Piston material: Aluminum with E = 10 x 106 psi and ν = 0.3Force on tip of beams = 10 lbf

Software VersionMSC.Patran 2005r2MSC.Nastran 2005r2b


Key Concepts and Steps:Database: create a database with Analysis Code = MSC.Nastran and Analysis Type = StructuralGeometry: create a 5 x 1 x 1.5 parametric solidElements: create 2D Quad4 mesh on the four long sided faces of the solidLoads/BCs: apply concentrated force at free end of cantilevered beam. Constrain cantilevered end of beam.Materials: create material properties for beam; use aluminum properties.Properties: create properties for Quad4 elements. They include both bending and membrane properties.Analysis: Solution Type = Nastran Linear Static, Solution Sequence = 101, Method = Full RunAnalysis: access analysis results by attaching the XDB file to databaseResults: view both the deformation and stress results


Key Concepts and Steps: (continued)Database: create a database with Analysis Code = MSC.Nastran and Analysis Type = StructuralGeometry: create a <5 0 0> curveElements: mesh the curve with 1D Bar2 elements. Create a rigid link (MPC) for force application at the free end of the cantilevered beam.Loads/BCs: apply a concentrated force at the free end of the MPCMaterials: create material properties for beam; use aluminum properties.Properties: create properties for Bar2 elements. Use the Beam Library and select the rectangular cross-section option.Analysis: Solution Type = Nastran Linear Static, Solution Sequence = 101, Method = Full RunAnalysis: access analysis results by attaching the XDB file to databaseResults: view both the deformation and stress results Results: compare the 2D and 1D model results


Step 1. Create a Database for 2D Element Model

Create a new database for 2D element model.

a. File / New.b. Enter cant_beam_2D 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

b

e

f

d

c g


Step 2. Create Solid Geometry

a. Geometry: Create / Solid / XYZ.

b. Select on Vector Coordinates List and enter < 5 1 1.5 >.

c. Apply.d. Change view to Iso 1 View.

a

b

c

d


Step 3. Create 2D Element Mesh

a. Elements: Create / Mesh / Surface.

b. Element Shape: Quad. c. Mesher: IsoMesh.d. Topology: Quad4.e. Click on Surface List and

select the four long faces of the solid, not including the end faces.

f. Uncheck Automatic Calculation.

g. Enter 0.5 for Global Edge Length.

h. Apply.

a

g

h

fe

bcd


Step 4. Display Free Edges

a. Elements: Verify / Element / Boundaries.

b. Display Type: Free Edges.c. Apply.d. As shown in the figure,

yellow lines along the solid edges should appear

a

b

c


b

Step 5. Connect the Elements Together

a. Elements: Equivalence / All / Tolerance Cube.

b. Apply.

Notice that magenta colored circles are drawn where nodes are equivalenced.

a


Step 6. Display Free Edges Again

a. Elements: Verify / Element / Boundaries.

b. Display Type: Free Edges.c. Apply.

No longer do the yellow lines in the long direction appear. This means that the adjacent 2D quad elements are connected.

a

b

c


Step 7. Apply a Force at One End

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

b. Select on New Set Nameand enter force.

c. Input Data.d. Enter <0 -10 0> for Force

<F1 F2 F3 >.e. OK.f. Select Application Region.g. Geometry Filter: Geometry.h. Click on Select Geometry

Entities.i. Select Point or Vertex icon

from the Pick Menu.

a

bc

d

ef

g

h

i


Step 7. Apply a Force at One End (cont.)

a. Turn on the Point labels.b. Select on the point (Point 7)

as shown in the figure.c. Add.d. OK.e. Apply.

Close-Up

bc

d

a

Note that selecting Point 7 and Vertex Solid 1.2.2.2 is equivalent.


Step 8. Create Constraints

Constrain beam at other end, fixing all six degrees of freedom at all nodes.

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

b. Select on New Set Name: and enter fix_end.

c. Select Input Data.d. Enter <0 0 0> for

Translations <T1 T2 T3 >and Rotations <R1 R2 R3>.

e. OK.f. Click on Select Application

Region.g. Select Geometry for

Geometry Filter.h. Click on Select Geometry

Entities.i. Select Curve or Edge icon

for the picking.

a

b

c

d

ef

g

h

i


a. Select the four solid edgesas shown in the figure.

b. Add.c. OK.d. Apply.

Step 8. Create Constraints (Cont.)

Select these edges a

b

c


Step 9. Create Material Properties

a. Materials: Create / Isotropic / Manual Input.

b. Select on Material Nameand enter aluminum.

c. Select Input Properties.d. Enter:

Elastic Modulus: 10e6.Poisson Ratio: 0.3.

e. OK.f. Apply.

a

b

c

d

ef


Step 10. Create Element Properties for the 2D Quad Topology

a. Properties: Create / 2D / Shell.

b. Option(s): Homogeneous / Standard Formulation.

c. Select Property Set Nameand enter alum_2D.

d. Select Input Properties.e. Click on Material Property

Name icon and select aluminum under Select Existing Material.

f. Thickness: 0.1.g. OK.

a

b

c

d

e

f

g


Step 10. Create Element Properties for the 2D Quad Topology (Cont.)

a. Click on Select Members.b. Select the four long solid

faces. c. Add.d. Apply.e. Turn off the Point labels.

a

b

c

d


Step 11. Check Assignment of Loads and BC’s to Load Case

a. Load Cases: Modify.b. Select Default in Select

Load Case to Modify.c. Check that all Loads and

BC’s are selected.d. Cancel.

a

b

c

d


Step 12. Run the Analysis

Run the analysis of the model.a. Analysis: Analyze / Entire

Model / Full Run.b. Select Solution Type.c. Choose LINEAR STATIC for

Solution Type.d. OK.e. Apply.

b

c

d

a


Step 13. Read Results Under Analysis

Attach the .xdb file to read the results.

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

b. Click on Select Results File.

c. Select and attach cant_beam_2D.xdb.

d. OK.e. Apply.

c

d

a

b

e


Step 14. View Results

a. Results: Create / Deformation.

b. Select Results icon.c. Select A1:Static Subcase

under Select Result Cases.d. Select Displacements,

Translational under Select Deformation Result.

e. Show As: Resultant.f. Apply.

a

b

c

d

e


Step 14. View Results (Cont.)

a. Results: Create / Fringe.b. Select A1:Static Subcase

under Select Result Cases.c. Select Stress Tensor under

Select Fringe Result.d. Quantity: X Component.e. Select Plot Options button.f. Coordinate Transformation:

Global.g. Apply.

a

b

c

d

e

f


Step 15. Stress Results and Save a Copy of the Database

Display X component of stress fringe plot. Save a copy of this database for use later for a transient simulation.

a. File / Save a Copy as...b. File name:

cant_beam_transient.db.c. Save.d. File / Quit.

a

d


Step 16. Create a New Database for 1D Element Model

Create a new database for 1D element model.

a. File / New.b. Enter cant_beam_1D 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

b

e

f

d

cg


Step 17. Create Curve Geometry

a. Geometry: Create / Curve / XYZ.

b. Select on Vector Coordinates List and enter < 5 0 0 >.

c. Apply.d. Change view to Iso 1 View.

a

b

c

d


Step 18. Create 1D Element Mesh

a. Elements: Create / Mesh / Curve.

b. Topology: Bar2.c. Click on Curve List and select

the curve.d. Enter 0.5 for Global Edge

Length.e. Apply.

a

b

c

d

e

c


Step 19. Create a Rigid Link at Force End

Create a rigid link at the end of the beam where the load will be applied. That will offset the load so it will be applied equivalent to that for the prior 2D model.

a. Turn on the node labels.b. Elements: Create / Node /

Edit.c. Select on Node Location List

and enter [5, 0.5, 0.75].d. Apply.

This will give Node 12, where the load will be applied.

b

d

a

c


Step 19. Create a Rigid Link (Cont.)

a. Elements: Create / MPC / RBE2.

b. Select Define Terms.c. Select Create Dependent.d. Turn off Auto Execute.e. Click on Node List and

select Node 11 from the figure.

f. DOFs: specify UX, UY, UZ, RX, RY, RZ.

g. Apply.

a

bc

de

f

g


Step 19. Create a Rigid Link (Cont.)

a. Notice that Create Independent is active now.

b. Click on Node List and select Node 12 from the figure.

c. Apply.d. Cancel.e. Apply.

Notice that a magenta colored line was drawn from Node 11 to Node 12. This represents the rigid RBE2 MPC.

a

b

c d


Step 20. Create a Concentrated Force

Apply a force at the free end of the MPC.

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

b. Select on New Set Nameand enter force-1D.

c. Input Data.d. Enter <0 -10 0> for Force

<F1 F2 F3 >.e. OK.f. Select Application Region.g. Geometry Filter: FEM.h. Click on Select Nodes and

select Node 12.i. Add.j. OK.k. Apply.

a

b

c

d

ef

g

h

i

j


Step 21. Apply Constraints at Other End

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

b. Select on New Set Name: and enter fix_it.

c. Select Input Data.d. Enter <0 0 0> for

Translations <T1 T2 T3 >and Rotations <R1 R2 R3>.

e. OK.f. Click on Select Application

Region.g. Select FEM for Geometry

Filter.h. Click on Select Nodes and

select Node 1.i. Add.j. OK.k. Apply

a

bc

d

ef

g

h

i

j


Step 22. Create Material Properties

a. Materials: Create / Isotropic / Manual Input.

b. Select on Material Nameand enter aluminum2.

c. Select Input Properties.d. Enter:

Elastic Modulus: 10e6.Poisson Ratio: 0.3.

e. OK.f. Apply.

a

b

c

d

ef


Step 23. Create Element Properties for the 1D Beam Topology

a. Properties: Create / 1D / Beam.

b. Option(s): General Section / Standard Formulation.

c. Select Property Set Name and enter alum_1D.

d. Select Input Properties.e. From the Material Property

Sets, select aluminum2 for Material Name.

f. Select Create Sections Beam Library.

a

b

c

d

e

f


Step 23. Create Element Properties for the 1D Beam Topology (Cont.)a. In New Section Name:

cross_sect.b. Select the rectangular cross-

section button and enter: W = 1.5, H = 1.0, t1 = 0.1, t2 = 0.1.

c. Calculate / Display.d. OK.e. Enter < 0 1 0 > in Bar

Orientation.f. OK.g. Click on Select Members and

select Curve 1.h. Add.i. Click Apply.j. Display the cross-section to

scale under Display / Load/BC /Elem. Props…using Beam Display / 3D: FullSpan + Offsets.

k. Click Apply.

a

b

c

Notice that the name “cross_sect” now appears in the Input Properties form under Section Name. Area, Inertia and Torsional Constant have values. The values are ghosted out so that to change them it is necessary to use the Create Section button.

d

e

f

b


a. This is the entire 1D model. A representation of the cross-section is shown, even though the geometry is only 1D.

Step 23. Create Element Properties for the 1D Beam Topology (Cont.)


Step 24. Check Assignment of Loads and BC’s to Load Case

a. Load Cases: Modify.b. Select Default in Select

Load Case to Modify.c. Check that all Loads and

BC’s are selected.d. Cancel.

a

b

c

d


Step 25. Run Analysis for 1D Beam

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

b. Select Solution Type.c. Choose LINEAR STATIC for

Solution Type.d. OK.e. Apply.

b

c

d

a


Step 26. Read Results Under Analysis

Attach the .xdb file to read the results.

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

b. Click on Select Result File.c. Select and attach the

cant_beam_1D.xdb.d. OK.e. Apply.

c

d

a

b

e


Step 27. View Results

Create a Deformation plot .a. Results: Create /

Deformation.b. Select Results icon.c. Select A1:Static Subcase

under Select Result Cases.d. Select Displacements,

Translational under Select Deformation Result.

e. Show As: Resultant.f. Apply.

a

b

c

d

e


Step 27. View Results (Cont.)

a. Results: Create / Fringe.b. Select A1:Static Subcase

under Select Result Case(s).c. Select Stress Tensor,

Bending under Select Fringe Result.

d. Quantity: X Component.e. Apply.

a

b

c

d


a. Compare Results.b. This ends this exercise.

Step 28. Compare 2D and 1D Model Results

workshop 13 cantilevered beam using 1d or 2d … · pat301, workshop 13, december 2005...

Documents