THE ENERGY EQUATION FOR PROCESSES OF HEAT AND MASS-TRANSFER AND PHASE-TRANSFORMATIONS IN POROUS BODIES

This paper presents the derivation of the energy equation used to desc ribe the processes of heat and mass transfer and phase transformations in porous bodies based on the procedure of bulk averaging of the phys ical parameters in accordance with the approach described by Whitaker [2]. The flow of bound matter in the form of liquid, its vapor, and no ncondensing gas is assumed to be slow. The equation is written in a di vergent form convenient for numerical calculations. By combining the e nergy equation and the continuity equation for vapor, the unknown func tion of the source of vapor is eliminated from the resultant system of heat and mass transfer equations.