Week 5 Sphere pressing on a plate

Objective: To simulate the sphere pressing on a plate and to capture the plastic deformation on the plate due to the sphere.

Materials:

	Youngs Modulus(GPa)	Poission Ratio	Yield Strength(MPa)	Ultimate Strength(MPa)
Structural Steel	2E+005	0.3	250	460
Structural Steel NL	2E+005	0.3	250	1450

Model:

The sphere is assigned structural steel and the Plate is assigned with Structural Steel NL.

Connections:

Contact Sets:

A contact set is created between the outer surface of the sphere and the Top of the plate. A frictional contact is introduced between the sphere and plate with a frictional coefficient of 0.74.

Symmetry:

In order to simplify the solving process, only 1/4 of the model is taken. Hence, symmetry is inroduced to cover the entire model.

Symmetry 1:

Symmetry 2:

Mesh:

The default mesh is used. It can be refined to get more accurate results.

Nodes:     5728

Elements: 1770

Analysis Settings: 

The solver process is divided into 3 steps. Large deflection is turned on and the solver type is direct.

1. Displacement:

this is done to provide the distance upto which the sphere will travel. 

2. Fixed support:

The plate is fixed in order to prevent slipping.

Results:

1. Deformation:

2. Equivalent Strain:

From the video attached it can be concluded that the plastic deformation has occured as the plate does not return to its original shape when the sphere is retracted.