Emergence of inertial waves from coherent vortex source in Yukawa medium

Akanksha Gupta; Rajaraman Ganesh

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arXiv · 1901.07259

Emergence of inertial waves from coherent vortex source in Yukawa medium

Akanksha Gupta·Rajaraman Ganesh

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Abstract

The evolution of isotropic, nondispersive, inertial wave, emerging from an unsteady initial coherent vortex is studied for strongly correlated Yukawa medium using 2D molecular dynamics simulation. In this study, the effect of azimuthal speed of vortex source, strong correlation, large screening and the compressibility of the medium over the propagation of generated inertial wave have been presented. It has been observed that these inertial waves only exist when the speed of the vortex source (U_0) is larger or equal to the longitudinal sound speed of the system. Estimated speed of the nonlinear wave (C_NLW ) is found to be always larger than the transverse sound speed (C_t ) of the system for the range of coupling and screening parameters. In this study, we find that spontaneously generated nonlinear inertial wave speed in Yukawa medium is suppressed by compressibility and dust-neutral a drag of the system and is less sensitive to coupling strength. A transition from incompressible to compressible Yukawa liquid is observed. This transition depends on the screening parameter and azimuthal speed of vortex source. The existence of a critical Mach number Mc~0.35 is found above which nonlinear wave is found to exists, indicating the compressible nature of the medium.

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Akanksha Gupta, Rajaraman Ganesh. 2019-01-22. Emergence of inertial waves from coherent vortex source in Yukawa medium. https://arxiv.org/abs/1901.07259

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