Numerical simulation and analysis of heat transfer performance of new airfoil fin printed circuit heat exchangers

Abstract

The airfoil fin printed circuit heat exchanger (PCHE) is very suitable for use as the heat exchangers in the supercritical CO2 Brayton power generation cycle due to its multiple advantages. However, in most previous studies, the new fin designs have complex curved surface geometries, which would bring difficulties in their manufacturing. Therefore, in this study, some simple fin structures based on the modification of traditional NACA0018 airfoil fin are proposed to enhance the heat transfer performance of PCHE. The influence of different structure modification shapes, size and positions on the overall PCHE performance are examined by numerical simulation. The results revealed that setting concave with a radius of 0.3 mm in the flow boundary zone (i.e. Type-VI) can significantly improve the thermal hydraulic performance of the fin channels. By comparing the local thermal hydraulic performance with the prototype fin, the Type-VI fin shows the advantages of reducing the fluid pressure difference resistance near the fin wall and increasing the impact area of the fluid on the fin, resulting in its j factor can be increased by 4.37 % to 7.16 %, f factor reduced by 0.45 % to 1.77 %, and η increased by 5.20 % to 9.10 %.