stress distribution

Hi,

I am seeking clarification regarding the calculation of stress distribution for spheres with depth. Theoretically, the stress should follow the relation 𝛾 × depth. I have explored using micro-stress methods for this purpose and followed the example code provided on the official website.

The website mentions: “Stress fields can be generated by combining the volume returned by TesselationWrapper with the per-particle stress given by bodyStressTensors. Since the stress from bodyStressTensor implies a division by the volume of the solid particle, one has to re-normalize it in order to obtain the micro-stress.”

Following this approach, I applied the re-normalization step as instructed. However, the results differ significantly from the theoretical 𝛾 × depth. Interestingly, when I omit the re-normalization step, the results align closely with the theoretical stress values.

This raises my primary question: Is re-normalization always mandatory, or is it necessary only under specific conditions, such as when particles vary in size?

I have attached a Minimal Working Example (MWE) for reference.

Thank you for your assistance. stress_distribution.py