Numerical Simulation Study on Turbulent Heat Transfer Characteristics of Supercritical Fluid in Micro-Fin Tubes

Abstract In consideration of the technical requirements for compact and efficient heat-exchange equipment in industrial fields, such as sludge incineration heat utilization, solar thermal power generation and aerospace, this paper analysed the supercritical nitrogen flow and heat transfer processes in square straight micro-fin tube, triangle straight micro-fin tube and smooth circular tube under different Re numbers, and obtained the changes in velocity field, local turbulence intensity, average Nusselt number and resistance coefficient of supercritical fluid in micro-fin tubes. Moreover, it was found that the introduction of micro fin was able to improve the turbulent heat transfer performance of supercritical fluid in tubes within certain Re number range.