MPM·2024·ONGOING

MPM Material Studies

One MPM setup, three materials. By keeping the transfer and grid steps fixed and swapping only the constitutive model, the differences between sand, snow, and foam become easy to see and tune.

WRITE-UP

Setup

APIC transfers on a fixed background grid; the only thing that changes per material is the stress model — Drucker-Prager for sand, a compressible elastoplastic model for snow, and a soft foam variant.

Findings

Sand lives or dies on the friction angle; snow needs the hardening term to fracture believably; foam is mostly about the recovery rate. Same rig, very different behaviour.

NOTES

Grid resolution matters more than particle count for crisp fracture.
CFL is unforgiving here — substep on fast impacts.