超声速来流中的支板辅助喷注掺混特性研究

Mixing characteristic and flow features of pylon-aided fuel injection into a supersonic crossflow

摘要: 采用Reynolds-averaged Navier–Stokes（RANS）数值方法研究了马赫数2.95超声速横向来流中的支板辅助燃料喷注掺混特性。在射流与横向来流动量比7.7工况下进行了数值模拟，并与无支板的普通壁面喷注工况进行对比。研究结果表明：产生于支板前缘的诱导激波被观测到汇聚于分离激波，在支板辅助喷注工况下，反转旋涡对（CVP）结构更多，边界层内燃料扩散速度更快、射流穿透更深，最终体现为在未增大流动压力损失的前提下，支板极大地提升了燃料混合效率。此外，还阐述了支板对燃料–空气混合增强的作用机理。

Abstract: Flowfield structures of pylon-aided fuel injection of a sonic jet into a supersonic crossflow with Ma_∞=2.95 have been investigated by RANS method. One case has been studied for jet-to-crossflow momentum flux ratios of 7.7, and the results are compared with those obtained by normal injection of a single jet from a flat plate without a pylon. Upstream of the jet orifice, the detached shock generated at the leading edge of the pylon is identified by inserting with the separation shock. Elevation of the jet plume height facilitates the mixing of the jet and the main flow. More CVP structures make pylon-aided fuel injection cases a better mixing performance. Besides, the mechanism of mixing enhancement resulting from the pylon is also elaborated in the present work.