摘要
为了了解多单元直排塞式喷管的高度特性和选择好的塞锥型面设计方案,从曲线坐标下的三维平均雷诺N-S方程出发,用k-ε两方程湍流模型封闭方程组,采用二阶精度无波动、无自由参数的耗散差分格式(NND格式),发展了模拟塞式喷管三维流场的数值程序。计算了圆形喉部方形出口内喷管和直排塞锥的流场及塞式喷管的高度特性,比较了优化型面与简化型面的高度特性,研究了塞式喷管高度补偿特性和截短塞锥与全长塞锥在高度特性上的差别及其产生原因。计算表明,塞式喷管在低空具有高度补偿能力;塞锥截短将给塞式喷管的性能带来损失,在低空尤为明显;从低于设计压比的某个压比开始,塞式喷管失去高度补偿能力而进入类似钟型喷管的膨胀状态,截短塞锥将使塞式喷管失去高度补偿能力的压比降低;简化设计的塞锥型面会带来性能上的损失。
To understand the altitude characteristics of linear clustered aerospike nozzles and select appropriate methodology for designing plug contour,a numerical program was developed.It was based on threedimensional Reynolds averaged NavierStokes equations and low Reynolds number kε equations by employing twoorder Nonoscillatory and Nonfreeparameters Dissipative finite difference scheme (NND scheme).The flow fields of round throat rectangle exit cell and linear plug were studied and the altitude characteristics of aerospike nozzles were computed.Comparison between optimized plug contour and simplified contours were made.The altitude characteristics of aerospike nozzles with different truncated plugs and full plugs were presented and their differences and generating causes were also discussed.It is suggested that aerospike nozzles have altitude compensation capacity at low altitude.Plug truncation reduces aerospike nozzles' performance,especially at low altitude.It is shown that when NPR higher than an NPR which is lower than the design NPR,aerospike nozzles lose altitude compensation capacity and expand gas like bell nozzle.It is found that simplified contours cause performance losses.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2003年第5期496-501,共6页
Journal of Astronautics
基金
国家863-2资助项目(863-2-3-4-10)
关键词
塞式喷管
高度特性
塞锥型面
性能
Aerospike nozzle
Altitude characteristics
Plug contour
Performance
