Interface-resolved simulation of particles with different shapes in sediment transport

Sediment transport is a dynamic process with significant implications for landscapes and human activities. The movement and collision of sediment particles have a profound impact on the surrounding flow field. Among various flow configurations and particle properties, the shape of particles plays a crucial role in the fluid-particle interaction process. In this work, we employ numerical simulations to investigate sedimentation transport for different particle shapes, including spherical particles, oblate particles, and their mixtures.

 

To accurately capture the complex interactions between the flow and particles, we employ the immersed boundary method. This approach allows us to resolve the intricate fluid-particle interactions that cannot be adequately represented using a point particle model. Furthermore, collisions between particles are modeled using a linear spring-dashpot system, with the Adaptive Collision Time Model employed to calculate the contact force.

 

From simulations, we observe ripples during particle transport. By comparing particle velocities and angular velocities among different cases, we gain insights into the influence of particle shape on particle movement. Additionally, we examine the mean shear stress and its components, including the viscous contribution, Reynolds shear stress, and fluid-particle interaction. The analysis provides a comprehensive understanding of how each component affects the shear stress in the flow.