We study how grain shapes impact multiphase flow in porous media in the
quasi-static regime. An extended pore-network model with consideration
of menisci pinning at sharp edges of grains is presented. Our results
show that the effective contact angle distribution during displacement
widens as the grain becomes more angular, which consequently modifies
the macroscopic fluid invasion morphology. By analyzing various
characteristic metrics during displacement, including capillary pressure
signal, Haines jump size distribution, and fractal dimension, our
results highlight the profound influence of particle shape on the
multiphase flow.