Force fluctuations on a wall in interaction with a granular lid-driven cavity flow

Area of Science:

• Fluid Dynamics
• Granular Physics
• Computational Physics

Background:

• Lid-driven cavity flow generates complex dynamics.
• Boundary walls experience force fluctuations.
• Understanding these forces is crucial for engineering applications.

Purpose of the Study:

• Investigate force fluctuations on a boundary wall in lid-driven cavity flow.
• Quantify the impact of macroscopic inertial number on these forces.
• Analyze force distributions across different spatial scales.

Main Methods:

• Numerical simulations using the discrete-element method.
• Analysis of time-averaged cavity dynamics.
• Measurement of force time series autocorrelation and grain-wall force distributions.

Main Results:

• Macroscopic inertial number dictates grain-wall force distributions at all scales.
• Force distributions evolve from exponential to Gaussian with decreasing inertial number.
• Transition from quasistatic to dense inertial flow observed with changes in force distributions and system memory.

Conclusions:

• The macroscopic inertial number is a key parameter controlling force fluctuations.
• Flow regime transitions are identifiable through force distribution analysis.
• System memory loss correlates with the transition to dense inertial flow.