Entropy generation on a three-gas crossflow heat exchanger with longitudinal wall conduction

This study investigates the entropy generation in a crossflow heat exchanger including three gas streams and the effect of longitudinal wall conduction on the entropy generation. Using the numerical method, this study calculates the exit mean temperature of each stream, and then computes the number of entropy generation units. The results indicate that the entropy generation increases with the decrease of inlet temperature of gas stream 3 and the decrease of inlet temperature ratio of gas streams 1 to 2. In addition, the results show that the longitudinal wall conduction raises the entropy generation and that this raising increases with increasing NTU when heat capacity rate ratio of stream 1 is 0.5. (C) 2001 Elsevier Science Ltd.