Abstract
The pressure loss in solid-liquid two-phase flows is considered to be closely related to the motion of particles flowing in a pipe. In this paper, collisions among particles in solid-liquid flows in a horizontal pipe was observed with a high speed video camera. The frequency of collisions was obtained as a function of height. It reached a maximum in the vicinity of the surface of a moving bed, and decreased with an increase of height. The averaged value of impact and lift-off angle were approximately zero, and the shapes of frequency profile of both angles were almost symmetrical.
A simulation model of solid-liquid flows with taking into account the collisions among particles was established based on the experiments, and a numerical simulation was carried out to determine the motion of particles. The simulator gave almost the same particle trajectories, profiles of the particle velocity, and solid concentration as the experiments. Therefore, the present simulation model was confirmed to be reasonable.