Force fluctuations experienced by a boundary wall subjected to a granular flow in two distinct systems

The present paper describes a numerical study of force fluctuations experienced by a boundary wall subjected to a granular flow on two distinct systems, namely a lid-driven cavity and an immersed wall system. Though the two systems exhibit different time-averaged dynamics, the force fluctuations experienced by the boundary wall show robust features in terms of the shapes of the probability density distributions and auto-correlation functions, under a wide range of boundary confinement pressure and shearing velocity imparted to the granular flow at the top of the system. This study identifies the key link between the grain-wall force fluctuations and the μ (I )–rheology while moving from quasistatic to inertial regime.