Effects of Soret and Dufour numbers on MHD thermosolutal convection of a nanofluid in a finned cavity including rotating circular cylinder and cross shapes

Abstract

This study considers a more complex problem by introducing magnetohydrodynamic (MHD) thermosolutal convection of a nanofluid in a square cavity including dual rotation amongst an outer circular cylinder and an inner cross shape. The influences of the length of a cross shape LCros, a dimensionless time parameter τ, Hartmann number Ha, Soret number Sr, Dufour number Du, solid volume fraction ϕ, an inclination angle of a magnetic field γ, and Rayleigh number Ra on the heat/mass transfer and nanofluid movements within a cavity are examined. Three different thermal/solutal boundary conditions of an outer circular cylinder carrying (Tc & Cc) (case 1), (Th & Ch) (case 2), and adiabatic conditions (case 3) are conducted. The inner cross shape is kept at Th and Ch. The obtained numerical simulations revealed that the changes in the thermal/solutal boundary conditions have a good role in controlling the thermosolutal convection and nanofluid speed within a cavity. Increasing the length of a cross shape LCros enhances the nanofluid speed and intensity of temperature and concentration within a cavity in cases 1 and 3. Case 2 gives the highest values of mean Nusselt number Nu¯ and Sherwood number Sh¯. The Rayleigh number is performing well in enhancing the nanofluid movements and heat/mass transfer within a cavity.