Multi-Objective Optimization of Asymmetric Plate Heat Exchanger with a Fish-Scale Corrugation Pattern

In many industrial applications, the significant differences in flow rates and physical properties between the hot and cold media of plate heat exchangers (PHEs) often lead to differentiated performance requirements. Asymmetric structural design is an effective approach to addressing these specific needs. In this paper, a novel fish-scale corrugated asymmetric plate heat exchanger (APHE) was designed and multi-objective optimization was performed based on the objectives of minimizing the water side pressure drop, ΔP, and maximizing the overall heat transfer coefficient, K. Numerical simulations of the fish-scale corrugated APHE were conducted with the Box–Behnken Design (BBD) in the Response Surface Methodology (RSM). The corrugation angle, corrugation pitch, and protrusion ratio were selected as geometric variables. Through Analysis of Variance (ANOVA), significant regression models were established for the two competing performance indicators. Subsequently, Pareto optimal solutions were identified using the fast and elitist non-dominated sorting genetic algorithm (NSGA-II). A comparison of the performances reveals that the novel APHE reduces ΔP by 47.13% and increases K by 5.77% compared to the original chevron-type PHE. Further analysis of the simulation data reveals that the convective heat transfer coefficient on the refrigerant side is increased by 24.06%. These findings substantiate the benefits of the asymmetric feature of the fish-scale protrusion and offer a comprehensive and effective design strategy for APHEs.