Thermal design and optimization of plate-fin heat exchangers based global sensitivity analysis and NSGA-II

Morris and Sobol global sensitivity analyses are firstly studied to evaluate the effects of the design parameters on the performance of plate-fin heat exchanger with serrated fins. Five design parameters such as the fin height, fin space, fin thickness and interrupted length and channel Reynolds number are selected as optimization parameters. Heat flow rate, total annual cost and entropy generation number are considered as objective functions. Furthermore, the five design parameters are optimized by NSGA-II, in which the effectiveness of the proposed algorithm is validated by comparing a previous approach. The results show that Reynolds number and fin space s play a dominant role on the performance of plate-fin heat exchanger with serrated fin. Meanwhile, the interaction effects among these parameters are significant on total annual cost and entropy generation number. Compared with one common design, the thermal performance factor of another common design and two optimal parameters increases 8.4%, 41.2% and 58.4%, respectively. Combining global sensitivity analysis and NSGA-II has the characteristics of easy to implement and high accuracy. Therefore, it is universal and can be used for various complex engineering applications to provide guidance for better selecting the suitable parameters.