Use a structured mesh with a sufficient number of element layers in the thickness direction.

Doing so captures results more accurately, as a free mesh may give lesser-quality tetrahedral and/or pyramid elements, leading to spurious high-stress concentrations at some locations.

Perform a loop test to verify the results of an inverse-solving analysis.

An inverse-solving analysis followed by a forward-solving analysis, or vice versa, is known as a loop test, as it should always result in the same geometry with the same solution.

Use a reversed sign to apply displacement type loading in the inverse-solving load step.

For more information, see Applying Loads in an Inverse-Solving Analysis in the Structural Analysis Guide.