Effect of flow distribution to the channels on the thermal performance of a plate heat exchanger

Plate heat exchangers are making their presence felt in the power and proce ss industry in the recent past. Hence, it has become necessary to model the ir temperature response accurately. The traditional way of modelling a plat e heat exchanger with equal flow in all the channels is unrealistic, and pr evious studies indicate that considerable differences remain in the flow ra tes in different channels. The present work brings out the effect of flow m aldistribution from channel to channel comprehensively. This poses a seriou s question about the usual method of analysis of the experimental heat-tran sfer data of the plate heat exchanger. Unlike previous studies, the present study indicates the importance of considering the heat-transfer coefficien t inside the channels as a function of flow rate through that particular ch annel. This eliminates the contradictory proposition of unequal flow rates but an equal heat-transfer coefficient. A wide range of parametric study ha ve been presented, which brings out effects such as those of the heat-capac ity rate ratio, flow configuration, number of channels and correlation of h eat transfer. The analysis presented here suggests a better method of heat- transfer data analysis for plate heat exchangers. (C) 2002 Elsevier Science B.V. All rights reserved.