Interrogation of Direct Numerical Simulation of Solid-Liquid Flow

In direct simulation the fluid motion is resolved numerically and the forces which move the particles are computed rather than modeled. This procedure opens new windows for understanding and modeling. Numerical methods are discussed based on body fitted moving unstructured grids and another on a fixed grid in which the portions of the fluid occupied by solids are forced to move as a rigid body by a distribution of Lagrange multipliers. Animation of the fluidization of 1204 spheres in 3D will be compared with experiments and the concept of fluidization of slurries in conduits by lift rather than drag will be framed in animation by direct simulation. Correlation for lift-off of single particles and the bed height of slurries fluidized by lift are obtained by processing data from numerical experiments.