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.
ZHENG Zhonghua
,
FAN Zhouqin
,
WANG Ziang
,
YU Bin
,
ZHANG Bin
. Numerical study of compressibility effect on flowfield evolution of vortex interaction[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2020
, 41(2)
: 123295
-123295
.
DOI: 10.7527/S1000-6893.2019.23295
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