Simulation of sphere pressing on a plate using ANSYS Workbench

OBJECTIVE:

To simulate a sphere pressing on a plate using ANSYS Workbench. The following objectives have to be satisfied.

To simulate using the material structural steel for sphere and structural steel non-linear for the plate. The plastic deformation has to be captured.

PROCEDURE FOR CASE SETUP:

1. Open ANSYS >> Drag and drop static structural in the project schematic window.

2. Go to engineering data for defining the materials given in the problem. Choose structural steel NL from the general non-linear materials library. The structural steel material is available by default.

3. Select the model tab to establish the meshing, contact definitions, and analysis settings definition. Rename the parts according to convenience. 

4. Go to contact and delete the default contacts. Now, create a manual contact between the sphere and plate. The contact type is frictional with a frictional coefficient of 0.74.

5. For meshing, an element size of 0.5mm is taken for the entire model. The mesh size below this provides a limitation to the academic limits available in the ANSYS. The final meshed model is shown in the figure below. 

6. Go to analysis settings. The number of steps defined for this analysis is 4. For all the time steps, the definition is shown in the figure below.

7. For the boundary conditions, fixed support is defined in the base of the plate. Displacement is given for the sphere. This is explained in the figure below.

8. The output requests for equivalent stress and equivalent elastic strain are placed for the plate and sphere are placed. The directional deformation along the Y-axis is also requested.

9. From the analysis settings, hit on solve to start the simulation. 

RESULTS AND DISCUSSION:

1. The equivalent stress for the whole setup obtained from the simulation is shown below.

2. The equivalent elastic strain obtained for the sphere is shown below.

3. The equivalent elastic strain obtained for the plate is shown below.

As shown in the above image, it is clear that the plastic deformation of the plate has occurred after removing the sphere from the plate.

4. The directional deformation along Y-axis is shown below.

5. The equivalent stress observed in the plate is shown in the figure below.

ANIMATION FILES:

1. The animation of equivalent stress for the whole setup is shown below.

2. The equivalent elastic strain obtained for sphere and plate is shown below.

3. The directional deformation along Y-axis is shown below.

4. The equivalent stress observed in the plate is shown below.

CONCLUSION:

From the above simulation, the following can be concluded.

1. The maximum equivalent strain for the plate is observed to be 0.022075

2. The maximum equivalent strain for the sphere is observed to be  0.0611

3. The directional deformation for the plate is 3.5188 mm in the negative Y-axis. Therefore, plastic deformation observed in the plate is 3.5188 mm.

4. The maximum stress observed in the plate is 4396.4 MPa.

From the animation, it can be seen that when the sphere is lifted to the original position, there is a plastic deformation observed in the plate. The sphere behaves in accordance with the displacement definition. Therefore, all the objectives are satisfied.