喷管气动参数对推力矢量影响的数值模拟

Effect of aerodynamic parameters of main and secondary flow path on thrust vectoring

关键词:  收敛扩散喷管  二次喷射  推力矢量控制  数值仿真

Key words:  Convergent divergent nozzle  Secondary injection  Thrust vector control  Numerical simulation

摘要:

以二元收扩喷管为对象,开展了基于二次流喷射的流体推力矢量技术研究。基于CFD技术,分析了激波矢量控制技术实现推力矢量的机理。重点分析了喷管落压比NPR,二次流总压比SPR,自由流马赫数Ma∞对流体推力矢量性能的影响。数值模拟结果表明:推力矢量的大小与斜激波的位置、角度以及流动分离区的大小有关。在所计算的参数范围内,推力矢量随喷管主次流的变化规律是:推力矢量角随NPR的增大逐渐减小;随SPR的增加,推力矢量角单调增加;在大落压比时,自由流马赫数对推力矢量的影响是有限的,而在低落压比时,自由流马赫数增加,推力矢量角减小。

Abstract:

A numerical investigation was presented to simulate the flow field resulting from transverse jet injection through the divergent flap of a 2D convergent divergent nozzle for thrust vector.Based on CFD technology,the two dimensional flow field structures of 2D convergent divergent nozzle with fluidic injection for thrust vector were conducted.Simulations were computed with free stream Mach number 0.3 to 1.2,with scheduled nozzle pressure ratios(from 13.89 to 4.5),and secondary to primary total pressure ratios(from 1.0 to 0.4).The numerical results indicate that nozzle pressure ratios and secondary pressure ratios have important effects on thrust vector.The free stream Mach number decreases thrust vector performance.The thrust vector decreases with increasing nozzle pressure ratios.As injection pressure ratio increases,thrust vectoring also increases.