Examples

All benchmarks, examples and applications cases to be run by Kratos. Note that unit tests are in Kratos repository and NOT here

View the Project on GitHub KratosMultiphysics/Examples

Hertz benchmark

Author: Vicente Mataix Ferrándiz

Kratos version: Current head

Source files: Hertz

Two meshes are avalaible, a fine mesh as well as a coarser one.

Case Specification

In this test case, we will consider the contact between a demi-sphere and a rigid plane, what is known as Hertz benchmark test. The reference solutions have been taken from the analytical solution of Hertz’s work that can be found in the reference section.

The following applications of Kratos are used:

The problem geometry as well as the boundary conditions are sketched below.

Hertz benchmark geometry.

The refined mesh:

Hertz mesh.

We consider the a sphere of 12.2474 meters of diameter with a load of 5.0e5 Pa.

The structure characteristic parameters are for the sphere (the plane is rigid):

The calculation is done in just one static step.

Results

The problem stated above has been solved using an structured mesh of hexahedron. The resulting deformation can be seen in the following image.

Solution

As well as the comparation with the reference solution. For the displacement we got a very good agreement with the analytical solution in both cases, in the case of the contact preassure we got a better approach in the finer case.

Vertical  displacement comparison. Contact pressure.

Error vertical  displacement Error contact pressure

References

Hertz Contact Calculator

Introduction to Elasticity/Hertz contact