Transport with a Spectrum of Fluid Particles

In this chapter, we discuss fluid mechanics and direct-contact transport processes with a swarm of bubbles or drops. The transport processes may involve exchange between streams which are of identical media or of different ones. The treatment of the multiple particle problem is in general very difficult. Interactions between fluid particles are difficult to describe accurately and the evaluation of the associated transport is challenging. However, with meaningful approximations, suitable models with a wide range of applicability can be constructed. Here, the salient features of some of these models and the corresponding results developed are discussed. At the outset, a brief discussion of the particle size and velocity distributions is provided.