English

Origin of lobe and cleft at the gravity current front

Fluid Dynamics 2019-09-25 v1

Abstract

In this paper the Rayleigh-Taylor instability (RTI) along the density interfaces of gravity-current fronts is analyzed. Both the location and the spanwise wavenumber of the most unstable mode determined by the local dispersion relation agree with those of the strongest perturbation obtained from numerical simulations, suggesting that the original formation mechanism of lobes and clefts at the current front is RTI. Furthermore, the predictions of the semi-infinite RTI model, i.e. the original dominating spanwise wavenumber of the Boussinesq current substantially depends on the Prandtl number and has a 1/3 scaling law with the Grashof number, are confirmed by the three-dimensional numerical simulations.

Keywords

Cite

@article{arxiv.1907.11389,
  title  = {Origin of lobe and cleft at the gravity current front},
  author = {Chenyue Xie and Jianjun Tao and Linsen Zhang},
  journal= {arXiv preprint arXiv:1907.11389},
  year   = {2019}
}