2007 Volume 15 Pages 34-38
Numerical simulation of impact of particles on a tubular wall in turbulent air flow has been conducted. It is found that the impact velocity normalized by the friction velocity decreased with the particle- Schmidt number. However, for larger Shmidt number, the impact velocity could not be expressed by the Schmidt number because the motion of particle depends not only on the turbulent diffusion but also on the inertia. The total impact velocity, Vtotal, increases with the air velocity, u0, and can be expressed by Vtotal = k u01.1. The result agrees qualitatively with Masda’s experimental data of the impact charge. The distribution of the total impact velocity agrees qualitatively with the experimental charge distribution.