Investigation of double-diffusive mixed convection effect on the particles dissolution in the shear flow using coupled SPM–LBM

Abstract

In the present study, double-diffusive mixed convection related to the heat and mass transfer of the solid particles dissolution in a shear flow was numerically investigated. For this purpose, the study employed the combined two-dimensional thermal-concentration smoothed profile-lattice Boltzmann method scheme. The governing equations of the flow, concentration and temperature fields are solved by applying the LBM. The interplay amongst the fluid–solid particle and the boundary condition of the no-slip at the interface of the fluid–solid particle is treated by using the SPM. Initially, a comparison made amongst the results obtained in the present numerical method and to those that had been obtained in the previous works, showing a well compatibility. Then, the impacts of Reynolds number, thermal and concentration Grashof numbers and buoyancy ratio on the flow characteristics and dissolution process have been addressed. Following that, a comparison is made amongst the impacts of pure forced convection and double-diffusive mixed convection on the solid particle dissolution behavior. It is shown that different competitive mechanisms have impact on the migration of the solid particles under the double-diffusive mixed convection; these are the particle mass force, the buoyancy force resulting from the fluid weight, the thermal convection and finally, the concentration convection. The numerical results also revealed the identification of the critical buoyancy ratio, with the dissolution time of the solid particles being sensitive to it.