高超声速飞行器激波控制减阻技术

Drag Reduction of Hypersonic Vehicles by Shock Control

针对高超声速飞行器巨大的激波阻力,采用数值方法研究了由钝头体、气动杆和侧向喷流构成的组合模型的减阻性能。侧向喷流将弓形激波推离气动杆,组合模型的再附激波明显弱于传统气动杆模型,其阻力系数比气动杆模型低了33.52%,从而验证了本文组合模型优异的减阻效率。进行了组合模型的影响因素分析,随侧向喷流总压比和气动杆的长度的增加,再附激波强度减弱,减阻效率升高,但减阻效率的变化速率逐渐减小。随喷口位置向下游移动,再附激波逐渐增强,减阻效率降低,且减阻效率的变化速率逐渐增加。此外本文还研究了以上参数对流场结构及钝头体压力峰值位置的影响。

For the huge shock wave drag of hypersonic vehicles,the numerical method is adopted to analyze the drag reduction efficiency of a combinational model,which consists of the spike,lateral jet and blunt body.The lateral jet pushes the bow shock wave away from the spike,the combinational model has significantly weaker reattachment shock wave than the spiked blunt body.The drag coefficient of the combinational model is 33.52%lower than that of the spiked blunt body,thus verifying the excellent drag reduction efficiency of the combinational model.The influencing factors of the combinational model are analyzed.As the total pressure ratio of the lateral jet and the length-diameter ratio of the spike increase,the reattachment shock wave gradually weakens,thus improving the drag reduction efficiency.However,the change rate of drag reduction efficiency gradually decreases.As the nozzle moves downstream,the reattachment shock wave gradually increases to reduce the drag reduction efficiency,and the change rate of drag reduction efficiency gradually increases.In addition,the effects of the above factors on the flow characteristics and the position of peak pressure of blunt body are also studied in this paper.