## 20.2. Controls - Global Erosion

A new global erosion option has been implemented that can be used to define global erosion criteria for all elements in the model. The global erosion options are only available for unstructured elements.

Three erosion criteria have been implemented and can be used in combination in an analysis:

- Global Erosion by Geometric Strain

  - You can define a single erosion strain that will be used for all elements in the model.

    - The minimum of the global erosion strain, and the local material erosion strain (if specified) will be used to check for element erosion.

- Global Erosion by Timestep

  - You can define a single erosion timestep that will be used for all elements in the model.

    - The maximum of the global and the local material based erosion timestep (if specified) will be used to check for element erosion.

- Global Erosion by Failure

  - You can turn on erosion by material failure for all materials.

    - Using erosion by timestep will activate the element timestep variable which can be used in postprocessing.

Release 18.2 - © ANSYS, Inc. All rights reserved.