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对一种类X43-A吸气式高超飞行器全流道开展了M7一级的三维数值仿真研究,深入探索了进气道处于起动状态和不起动状态时全流道的冷流流场结构和和气动力特性,且部分结果与实验数据进行了对比。研究结果表明:(1)前体横截面上存在显著的展向压强梯度,使得经过预压缩的气流偏离了进气道进口,但同时也减少了进入内通道的边界层气流,提高了进口流场的品质;(2)后体喷流股的膨胀过程受到了周围外流的显著干扰,因而沿流动方向其截面形状不断发生变化,如在喷口附近为近似矩形,而在后体末端附近则演化为近似三角形;(3)当进气道处于不起动状态时,其全流道流动结构发生了显著变化,进气道的外部压缩波系往复振荡,尾喷管出口的喷流股也在不停的膨胀和收缩,具有极强的非定常特征;(4)当进气道处于不起动状态时,全机的气动力特性呈周期性变化,升阻比的变化幅度较大,在最大、最小值分别可达起动状态的2倍和1/4倍。另外,升力、阻力系数的变化曲线之间存在一定的相位差;(5)与实验结果的对照表明,所采用的数值仿真方法具有较高的精度。
The M7-level three-dimensional numerical simulation of an X43-A aspirated hypersonic aircraft was carried out, and the structure of cold flow field and gas in the full flow passage when the inlet was in the start-up state and the non- Dynamic characteristics, and some results and experimental data were compared. The results show that: (1) There is a significant forward pressure gradient in the cross section of the precursor, which makes the pre-compressed air flow deviate from the inlet port, but also reduces the boundary layer gas flow into the inner channel and increases the inlet flow The quality of the field; (2) the expansion process of the rear body jet is significantly disturbed by the surrounding outflow, and its cross-sectional shape changes along the flow direction, such as near the nozzle near the rectangle, and near the end of the rear body (3) When the inlet is in the non-start state, its full-flow structure has changed significantly, and the external compression wave of the inlet oscillates reciprocatingly, and the jet flow at the outlet of the nozzle is also not (4) When the inlet is in the non-start state, the aerodynamic characteristics of the whole machine change periodically, and the variation range of the lift-drag ratio is larger. At the maximum, The minimum value of up to 2 times the starting state and 1/4 times. In addition, there is a certain phase difference between the curves of lift and drag coefficient. (5) The comparison with the experimental results shows that the numerical simulation method used has higher accuracy.