Effect of airfoil structure on flow and heat transfer characteristics of printed circuit heat exchanger
The performance of the printed circuit heat exchanger(PCHE),an important component in the supercritical carbon dioxide(S-CO2)Brayton cycle,affects the efficiency of the system.This study aims to improve the performance of airfoil PCHE by investigating the effect of the airfoil-fin structure on its flow and heat transfer performance.Herein,for the high-temperature return heaters in the S-CO2 Brayton cycle system,a numerical simulation method is used,with S-CO2 selected as the heat transfer medium.By comparing the flow and heat transfer performance of the airfoil-fin channels of NACA0020 with three different structures,we study the influence of the positional parameter of the maximum thickness of the airfoil fins on the chord length on the performance of the heat exchanger and analyze the rule of change in terms of the thermo-hydraulic performance,comprehensive indexes,overall fluidity,local performance,etc.Results show that the heat transfer performance increases as the maximum thickness of the airfoil fins approaches the leading edge of the airfoil along the chord length while maintaining a constant relative thickness in the airfoil-fin structure.Compared to the other two airfoil-fin channels,the airfoil-fin channel of NACA0020-20 exhibits a larger j factor and Nu of 2.7%—8.8%and 2.7%—8%,respectively,under the selected operating conditions.This airfoil-fin structure can effectively reduce the influence of the boundary layer and improve the heat transfer performance in the PCHE.Overall,its performance is even better than the other two airfoil fins.These results provide a certain basis for the structural design and performance optimization of the airfoil PCHE.
supercritical carbon dioxideheat exchangerairfoil finmaximum thicknessflow and heat transfer
国家科技期刊平台
NSTL
万方数据
维普
