ABSTRACT
In thermal processing of a mass of solid materials such as soil, fertilizers, seeds and grains, forage and silage, fruits and vegetables, cotton, tobacco, sugar beets as well as fluid materials such as liquid food and feed and slurries we are concerned with either heat transfer within a single solid particle condition or a multiple particle condition of a mass of the material. In either case the single particle situation is the starting point for describing the multiple condition case. If the particle does not move with respect to its surrounding fluid, heat transfer between it and the fluid must take place predominantly by simple conduction. When there is motion between the particle and the fluid, heat transfer by convection is also added. At elevated temperatures, radiation predominates the heat exchange and thermal emmisivity of the material, which will be discussed in another chapter, will become the dominating property. In this chapter we consider thermal conductivity, thermal diffusivity and unit surface conductance.
