ANALYTICAL SOLUTION FOR TRANSIENT-RESPONSE OF COUNTER FLOW HEAT-EXCHANGER WITH FINITE WALL CAPACITANCE

The Laplace Transform Method is applied to solve the transient respons e of the counter flow heat exchanger with finite wall capacitance prob lem. The mathematical model is based on three local energy balance equ ations which are solved assuming that only the fluid 1 inlet condition is perturbed (step change). As any counter flow problem could be redu ced to an adequate integral equation, collocation method is used for s olving such equation in the presented case. Results are given for the outlet temperatures of both fluids and temperature distributions for b oth fluids and the wall as an explicit analytical formula.