Fluid-thermal-structural analysis and structural optimization of spiral-wound heat exchanger

Based on the liquid-solid-thermal coupling method, the effects of configuration parameters on the flow characteristic, the heat transfer performance and the stress distribution on the tube bundle of spiral-wound heat exchanger (SWHE) were numerically studied. The results show that the shell-side flow patterns change from cross flow into oblique flow and the overall heat transfer coefficient increases firstly and then decreases with the increase of the wingding angle. The maximum stress intensity decreases firstly with the increase of the inlet flow rate and then decreases. The thermal stress takes a leading position in the tube bundle stress distribution attributed to the higher heat transfer temperature difference. With the inlet flow rate increasing, the heat transfer is enhanced and the temperature difference decreases which result in the decrease of the proportion of thermal stress and the increase of the impact of the primary stress. The optimal structure was obtained by the Multi-Objective Genetic Algorithm based on the Genetic Aggregation response surface. Compared with the original structure, the average comprehensive performance of three optimal candidates of SWHE increase by 57.64% and the maximum stresses intensity of the tube bundle are far less than the material allowable stress.