超声速流场中侧向射流的数值研究

Numerical investigation of lateral jets in supersonic cross-flows

通过数值方法研究拱柱体上侧向射流与超声速来流的相互干扰,为侧向射流喷管出口横截面几何形状的设计提供依据,实现高速飞行器机动飞行的姿态控制。采用多块嵌套网格并行算法,数值求解Navier-Stokes方程以及k-ω湍流模型,分别对四种不同横截面形状(相同面积的圆形、椭圆形、楔形以及倒置楔形)的射流喷管出口形成的流场进行了研究。圆形喷管出口的流场数值计算结果与实验结果相一致,表明本文采用的数值方法可靠以及网格分布合理。对比物面压力分布和射流干扰放大因子发现,对于长轴与来流垂直的椭圆形喷管出口,在射流上游一侧的物面附近形成较大的分离区以及较强的激波,由此产生的高压区有利于侧向射流对飞行器姿态的控制。

The complex interaction between a lateral jet and the supersonic external flow over ogive cylinder was investigated,so as to provide guidelines for jet nozzle design in terms of enhancing supersonic maneuverability of vehicles.Navier-Stokes equations were solved by using parallel solver on multi-block overset grids with k-ω turbulent model.Jets from four kinds of jet nozzle shapes with equivalent cross-sectional area（viz.circular,elliptical and wedge-shaped with opposite orientations） in supersonic cross-flow were calculated.The very good agreement between experimental and numerical studies for the circular nozzle credits the validity of current numerical method.By comparing the pressure coefficient distributions and jet-interaction amplification factor,it is found that the elliptical jet nozzle,longer in the crosswise orientations of external flow,will have larger separation region in size and stronger shocks ahead of the jet orifice,which leads to the greater increase of the local pressure and,as a result,enhances the jet-interaction amplification factor,viz.improving the efficiency of lateral control.