EFFECT OF LONGITUDINAL SEPARATOR SHEET CONDUCTION ON THE TRANSIENT THERMAL RESPONSE OF CROSS-FLOW HEAT-EXCHANGERS WITH NEITHER GAS MIXED

The present study investigates the transient temperature behavior of a direct transfer type, single-pass, crossflow heat exchanger with neit her gas mixed, accounting for the two-dimensional longitudinal conduct ion effect on the separator sheet. Numerical results show the variatio n of the mean exit temperatures of hot and cold gases. The approaching time to steady state is also presented to describe the influence of l ongitudinal conduction and number of transfer units. Finally, comparis ons among step, ramp, and exponential responses are demonstrated to di splay thermal performance deterioration due to the wall conduction eff ect.