radioss接触非线性分析

HyperWorks Solvers

The purpose of this tutorial is to demonstrate how to carry out nonlinear implicit small displacement analysis in OptiStruct, involving elasto-plastic materials, contact and continuing the nonlinear solution sequence from a preceding nonlinear loadcase.

Model and Loading Description

Figure 1 illustrates the structural model used for this tutorial: Two square solid blocks made of elasto-plastic steel material. The dimensions of the blocks and the material parameters can be obtained in the table below.

In the first nonlinear subcase, pressure loading is be applied to the top solid block, the top corners of which are constrained in X and Y directions. The top solid is in contact with the bottom solid, the bottom corners of which are constrained in X, Y and Z directions. The second nonlinear subcase is

to simulate the un-loading and is a continuation of the nonlinear solution sequence from the previous loading subcase.

Figure 1. Model and Loading Description

Units Length: mm; Time: s; Mass: Mgg; (Force: N; Stress: MPa)

Top block72 mm x 72 mm

Bottom block100 mm x 100 mm

Thickness of

20. mm

blocks

Material Steel, Elasto-plastic

Initial density ():7.90e-9 kg/mm3

Young's modulus (E):210000 MPa

Poisson coefficient (ν):0.3

Yield Stress (0):850.0 MPa

Imposed pressure1000.0 MPa, applied at the center of top block

The following exercises are included in this tutorial:

•Create elasto-plastic material

•Define contact between the two blocks

•Define nonlinear implicit parameters

•Set up NLSTAT analysis for the 1st subcase (loading)

•Set up NLSTAT analysis for the 2nd subcase (unloading)

•Submit job and view result

Exercise

Step 1: Import the model

unch HyperMesh.

2. A User Profiles Graphic User Interface (GUI) will appear, select OptiStruct.

3.Click OK. This loads the User Profile.

4.Click File>Open.

Note:If HyperMesh Desktop was launched, use:File > Open >

Model.

5.Select the file nlstat.hm located in the HyperWorks installation directory under

/tutorials/hwsolvers/optistruct/.

6.Click Open.

Step 2: Create the elasto-plastic material

First, the stress vs plastic strain curve for the material needs to be defined.

1.In the Tab area, click on the Utility menu. If not active, click View > Utility.

2.Click on the TABLE Create tool.

3.Click on Create/Edit Table and select the table type as TABLES1.

4.Click Next.

5.Click the radio button for Create New Table and enter the Name of the table as stress-

strain.

6.Next, populate the X and Y fields of the table, as shown below.

7.Click Apply.