Optimization Investigation on Wavy Channel Printed Circuit Heat Exchanger for Solar Energy Powered Brayton Cycle

Abstract

The Printed Circuit Heat Exchanger(PCHE) has received widely attention for their high effectiveness and compact size and they appear promising to be employed as the heat exchanger in solar thermal system. In this research, the thermal and hydraulic performance of the wavy channels for solar energy were investigated detailed in different amplitudes, inclined angles and channel diameters. The three-dimensional numerical analysis was performed by computational fluid dynamics(CFD) tool and the model is validated by comparing with previous experimental data. Besides, it was difficult to get the universal correlations of Nusselt number and friction factor for various geometrical parameters. In this article, the Kriging response surface method is applied to predict the friction factor and j factor for PCHE wavy channels in different geometrical parameters based on the CFD simulation results. The thermal-hydraulic characters predicted by Kriging response surface showed overall good agreement with the CFD results. Moreover, one of the most popular multi-objective genetic algorithms NSGA-II was adopted in optimization. to maximize j factor, while minimize the fanning friction factor.