Chapter 12 - Introduction to convective mass transfer

Abstract

Many heat transfer problems are accompanied by mass transfer. For example, water cooling in cooling towers used in thermal power plants involves both heat transfer and mass transfer. The immediate spread of a room freshener in an air-conditioned room is a typical example of mass transfer. Convective mass transfer closely resembles convective heat transfer. The analogy between mass transfer and heat transfer is especially true for low concentrations of the species in the fluid and low mass transfer rates of the species. In this chapter, the laws that govern diffusion and convective mass transfer are discussed. This is followed by a presentation of key equations for the determination of mass transfer coefficients for a gas flow over a volatile liquid or solid surface, based on the convective heat and mass analogy. Simultaneous heat and mass transfer for the case of air blowing over a wet surface is discussed.