English

Compressibility effects on quasistationary vortex and transient hole patterns through vortex merger

Fluid Dynamics 2020-01-01 v1 Pattern Formation and Solitons

Abstract

The effect of compressibility in hydrodynamic vortex merging has been discussed. In the past, in incompressible limit it has been observed that the merging of a collection of intense point-like vortices arranged uniformly outside a circular vortex, can lead to quasistationary vortex patch and transient hole pattern inside the patch via nonlinear merger process. These patterns are akin to \textquoteleft vortex crystals\textquoteright. Compressibility can introduce a natural acoustic scale to the problem. We find that the natural mode is independent of the number of point-like vortices and the amplitude scales linearly with compressibility. Further it has been identified that after merging, the system exhibits oscillation at a natural frequency together with its harmonics and beats with its own harmonics. The power of the frequency is found to scale as M2M^{-2}, where MM is the Mach number. Also the vortex crystals formed out of the merging process are found to melt faster as compressibility is increased.

Keywords

Cite

@article{arxiv.1802.03240,
  title  = {Compressibility effects on quasistationary vortex and transient hole patterns through vortex merger},
  author = {Rupak Mukherjee and Akanksha Gupta and Rajaraman Ganesh},
  journal= {arXiv preprint arXiv:1802.03240},
  year   = {2020}
}
R2 v1 2026-06-23T00:16:59.865Z