The study of double-diffusive convection has received considerable attention during the last several decades since this occurs in a wide range of natural settings. The origins of these studies can be traced to oceanography when hot salty water lies over cold fresh water of a higher density resulting in double-diffusive instabilities known as “salt-fingers,” Stern (35; 36). Typical technological...

The onset of double diffusive convection in a viscoelastic fluid-saturated porous layer is studied when the fluid and solid phase are not in local thermal equilibrium. The modified Darcy model is used for the momentum equation and a two-field model is used for energy equation each representing the fluid and solid phases separately. The effect of thermal non-equilibrium on the onset of double di...

In this paper, the effect of magnetic field on double-diffusive convection in couple-stress fluid saturating a porous medium is considered. By applying linear stability theory and normal mode analysis method, a necessary condition is derived which states that the viscoelastic double-diffusive convection at marginal state, cannot manifest as stationary convection if the thermal Rayleigh number R...

Abstract We study the properties of oscillatory double-diffusive convection (ODDC) in presence a uniform vertical background magnetic field. ODDC takes place stellar regions that are unstable according to Schwarzschild criterion and stable Ledoux (sometimes called semiconvective regions), which often predicted reside just outside core intermediate-mass main-sequence stars. Previous hydrodynamic...

Ocean waters often show layered structures especially where exchange flow between two basins occurs. These structures are often attributed to processes such as double.diffusive convection, internal waves, turbulent modulated mixing. In this paper by examining the vertical structures of temperature, salinity and density, of the middle parts of Caspian Sea it is shown that such layered structure ...