DETERMINING THE EFFICIENCY RATIO OF A HEAT-EXCHANGE APPARATUS

The author has proposed the general approach to determining the effi ciency ratio of heat-exchange apparatuses with diff erent schemes of motion of the heat-transfer agents on the basis of taking account of their fi nal equilibrium temperature. A procedure has been developed to calculate this temperature for a cocurrent-fl ow scheme of motion of the heat-transfer agents. The proposed approach makes it possible to consistently determine and to correctly compare the effi ciency ratios of heat-exchange apparatuses in counterfl ow, cocurrent fl ow, and crossfl ow of hot and cold heat-transfer agents. The author has given results of calculating the effi ciency ratios of heat-exchange apparatuses used in the production of liquefi ed natural gas. It has been shown that the maximum operating effi ciency of a heatexchange apparatus is attained with evaporation of the cold heat-transfer agent (coolant), which is characteristic of the processes of liquefaction of gases
   
Author:  O. M. Sokovnin
Keywords:  heat-exchange apparatus, cocurrent fl ow, counterfl ow, crossfl ow, effi ciency ratio, fi nal equilibrium temperature
Page:  545