Optimal design and numerical analysis of the rapid precooler
K.-X. Liu1, C.-A. Ai1, X.-R. Wang1, X.-F. Cai1, Y. Wang2
1Xi’an Research Institute of Hi-Tech, Xi’an, China
2National University of Defense Technology, Changsha, China
Keywords: система быстрого предварительного охлаждения, коэффициент теплообмена, шероховатость стенки, число диссипации энтранса, rapid precooler, heat transfer coefficient, wall roughness, entransy dissipation number
Abstract
Under the background of highly compact heat exchanger design core for the hypersonic aerospace precooled engine, a rapid precooler is designed and its performance is simulated under the high-altitude background. To this end, firstly, according to the known parameter range, a plate tube-fin rapid precooler unit with the optimal parameters is designed by using the genetic algorithm to find the minimum of the objective function-entransy dissipation number. Then introducing the roughness viscosity coefficient into the improved finite volume method, the effect of rapid heat transfer enhancement is obvious. The fin design can improve the heat transfer efficiency of the heat exchanger unit by 46.5 %. Finally, the rapid precooler is designed based on the unit. The performance simulation results indicate that the average temperature has decreased by 735 K for less than 1.5 ms hot air flowing through the rapid precooler at a high speed. The purpose of rapid heat transfer enhancement is achieved. Also we explore the influence of different hot air velocity and coolant velocity on rapid precooler and investigate the influence of scale effect on heat transfer performance.
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