EFFECTS OF PARTICLE SHAPE ON SETTLING BEHAVIOR OF PARTICLE CLUSTER

Abstract

The effects of particle shape on settling behavior of a sand particle cluster in an ambient water environment have been studied by a two-dimensional numerical experiment. The particle is ellipse of size about 1mm, and the aspect ratio α is varied without changing the volume. Due to the shape invariance under the rotation around its centroid, the circular particle shows distinct behavior from the elliptic particle in the initial stage of the sedimentation process. It is also revealed that the terminal velocity is decreased with increasing α and that the terminal velocity averaged over the particles in a cluster is slightly slower than that of an isolated particle.