腔体闭式流动控制的实验和数值模拟

利用数值模拟和风洞实验相结合的方法,研究了闭式流动腔体的流动特征及其设置圆柱控制杆后腔体内声压级(SPL, Sound Pressure Level)和压力分布的变化.数值模拟求解三维N-S方程,采用AUSM+计算格式,湍流模型采用Wilcox k-ω模型.实验在0.6m×0.6m超音速风洞中进行,在腔体底部布置了40个常规静压测量点和15个动态测压点.研究表明,在外流为超音速流时,闭式流动的腔体底部压力变化梯度较大,腔体底部和后缘的测压点的SPL值和频率关系曲线中没有明显的SPL峰值.实施控制后,腔体底部的压力变化梯度减缓,在腔体后缘分离区内的测压点SPL值降低,而前缘分离区内的测压点SPL值增加.

Experimental and numerical investigation of controls for closed cavity flow

The effects of control rod on the characteristic of the closed cavity flow and the sound pressure level (SPL) along the cavity bottom wall were investigated by means of the numerical simulation and wind tunnel test. Closed cavity flow was simulated by solving the 3D Favre-averaged Navier-Stokes equations using AUSM+ schemes and Wilcox k-ω turbulence model. The experiments were conducted in the supersonic wind tunnel with cross section of 0.6m×0.6m. The model was instrumented with 40 static pressure orifices and 15 dynamic pressure orifices. It was obtained that the closed cavity flow produces a strong adverse static pressure gradient over the cavity flow in supersonic flow, and there are not obvious peaks on the spectrum of the SPL. When the control rod is introduced, the longitudinal static pressure gradient becomes weaker along the bottom wall, and the spectrum of SPL near the front separation region of the cavity is increased and the spectrum of SPL near the rear separation region of the cavity is reduced.