ABSTRACT
A mode of mass transfer by particle-wall interaction is erosion of the wall or attrition of the particles depending on their properties and the dynamic of impact. The dynamics of impact are related to the kinetic energy of the particles, angle of impact, and friction coefficient of the surfaces. Using the Idealization of spherical particles, transport processes due to particle-particle collisions can be treated on a common basis. They include momentum, heat, mass, and charge transfers. To account for the shear resistance and heat transfer in a multiphase system, one must have a knowledge of the transport properties of phase Interactions. Extension to the case of charge transfer in turbulent pipe flow shows a significant bearing on the electrostatic safety in pneumatic transport. In conjunction with the drag or pressure drop characteristics of a cloud of particles and the modification of relations based on a single sphere, corresponding changes in the heat and mass transfer relations are expected.
