Skip to main content

A mechanism for layer formation in a double-diffusive fluid


The dynamics of layer formation by salt fingers from the uniform temperature and salinity gradients is studied by direct numerical simulations of the two-dimensional Navier–Stokes equations. It is shown that formation of steps in the model is caused by the parametric variation of the flux ratio ($\gamma\,{=}\,{\overline{wT}}/{\overline{wS}}$) as a function of the density ratio ($R$), which leads to an instability of equilibrium with uniform stratification. These unstable large-scale perturbations continuously grow in time until well-defined layers are formed. Subsequent evolution of the numerical staircases is explained by considering the secondary instabilities of a series of salt finger interfaces.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Journal of Fluid Mechanics
  • ISSN: 0022-1120
  • EISSN: 1469-7645
  • URL: /core/journals/journal-of-fluid-mechanics
Please enter your name
Please enter a valid email address
Who would you like to send this to? *


Full text views

Total number of HTML views: 0
Total number of PDF views: 88 *
Loading metrics...

Abstract views

Total abstract views: 240 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 22nd April 2018. This data will be updated every 24 hours.