横向喷流与超音速主流干扰流场的数值研究

NUMERICAL SIMULATION OF GASEOUS JET IN SUPERSONIC CROSSFLOW

采用欧拉方程与可压缩涡对模型相结合的数值方法，研究了超音速主流与横向喷流干扰流场的气动特性。喷流横截面用一对反向旋转的可压缩涡来模拟。采用有限元Ｏｓｈｅｒ格式及非结构网格数值求解二维欧拉方程以得到非等熵外流场的气动特性及弓波位置。将欧拉方程数值解结果与可压缩涡对流场解结果相结合以研究喷流的轨迹及喷流横截面的变化。最后给出了数值模拟结果并与工程估算结果进行了比较，表明本文所述方法是可行的。

A numerical method to simulate the single gaseous jet injected normally into a uniform supersonic crossflow is presented. The jet cross section is modeled in terms of a compressible vortex pair, which results from viscous and impulse forces at the periphery of the jet. The behavior of the vortex pair is then combined with mass and momentum balance along the axis of the jet to form a model, which describes the trajectory and mixing of the injected fluid. Due to the complication associated with a supersonic crossflow, a numerical technique is used to solve the inviscid outer flow and the position of the bow shock that envelops the jet. This solution, combined with the compressible vortex pair associated with the jet, allows prediction of trajectory of these types of gaseous jet. In fact, experimental data are used for comparison with the computed results, which shows that the present model is able to predict the overall jet penetration.