DIRECT-CONTACT HEAT-TRANSFER BETWEEN A RISING DISPERSED PHASE IN A COUNTERFLOW STREAM

A numerical model of a direct-contact evaporator is developed, which i s used to calculate performance information about direct-contact heat transfer between a rising dispersed refrigerant and a counterflow cont inuous fluid. Results are compared with the existing experimental data . The numerical scheme involves slicing the column of the evaporator i nto a finite number of horizontal slices and applying continuity, popu lation, and energy balances to each slice. Temperature and holdup rati o distributions through the evaporator are obtained for the operation of a 0.1-m-diameter column, using n-butane as the dispersed refrigeran t and distilled water as the continuous fluid. Results are given for a range of values of the initial drop diameter, mass flow rate of the d ispersed fluid, and mass flow rate of the continuous fluid.