涡相互作用作为冲压发动机喷注装置的典型抽象流动现象，研究其可压缩性影响对于认识包含化学反应的真实燃料喷射场具有一定基础理论价值。基于经过数值验证的可压缩Navier-Stokes算法与压力泊松方程初始条件设置方法研究流场可压缩性对涡相互作用演化过程的影响。结果表明，以较高涡旋马赫数表征的可压缩性在改变涡对形态的同时，具有延缓涡旋相互靠近，迟滞融合进程的作用。关于涡对系统开始融合的临界条件，可压缩相互作用开始的临界展弦比与无量纲时间相比于低速涡对明显提高。为在无量纲时间意义下统一不同马赫数涡对相互作用的进程，从涡心密度随时间变化规律出发在不可压涡对特征时间的基础上，初步构建了考虑可压缩性的时间尺度修正关系。
As a typical flow model of ramjet device, the study on the influence of compressibility in vortex interaction has fundamental value for understanding the actual fuel injection with chemical reactions. Based on the validated compressible Navier-Stokes solver and initial condition setup (pressure Poisson equation), the influence of compressibility on the evolution process of vortex interaction is investigated in this paper. The results show that the compressibility characterized by higher vortex Mach number changes the vortex pair morphology and delays the closing of the vortex rings, slowing down the merging process. With regard to the critical condition of vortex merging, the critical aspect ratio and the dimensionless time when the interaction begins are significantly higher than those in low velocity vortex pairs. In order to unify the interaction processes among the vortex pairs of different Mach number in the sense of dimensionless time, a compressible timescale correction relationship is constructed based on the temporal evolution of local density in vortex centre.
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