单元塞式喷管结构对性能影响的数值研究

Numerical investigation of aerospike nozzle configuration on its performance

关键词:  火箭发动机  塞式喷管  数值模拟

Key words:  Rocket engine  Aerospike nozzle  Numerical simulation

摘要:

从N S方程出发 ,采用二阶精度的NND格式对塞式喷管的流场进行了数值模拟。重点研究了单元喷管的倾角和塞锥的截断长度在偏离设计高度时对性能的影响。结果表明 ,不管是在低于还是高于设计高度 ,随着倾角的增加 ,内喷管对推力的贡献在减小 ,塞锥和底部对推力的贡献却增大 ,而侧喷管的最佳倾角却基本相同 ,都在全长型塞式喷管设计角度附近。截断后的塞式喷管虽然减小了重量 ,但不管是在低空还是高空 ,性能均低于全长型塞式喷管 ,因此增加底部的推力是提高性能的一个重要途径

Abstract:

The numerical simulations of the flow field around and aerospike nozzle cell were completed base on N S equations with Second order NND scheme.The attentions were paid to the effects of the two mainly parameters the angle of aerospike nozzle cell and the length of plug,on aerospike nozzle performance at the working conditions departing from design altitude.The results indicate that the thrust produced by intenal nozzle gets less and the thrusts produced by plug and base gets bigger with oblique angle increasing whether the flight level is lower or higher than the design altitude.And the optimal oblique angle nears to the angle that is designed at rated altitude both at low and high altitude.Though the truncated aerospike can reduce the mass of aerospike nozzle,there is a loss to the aerospike nozzle preformance whether at low or high altitude.It is suggested that the base is potential to improve the aerospike nozzle performance.