Production of entropy due to combined buoyancy and Marangoni convection in a cylindrical annular enclosure

The main purpose of the current analysis is to numerically describe the entropy generation due to collective thermocapillary and buoyancy determined convection in a perpendicular cylindrical porous cavity. The annular enclosure is occupied with MgO-Ag/water hybrid nanofluid. Two separate warmers of equal portions are located in the interior wall. The exterior wall of the cylindrical enclosure is set to be cold. The unheated section of the internal wall as well as the upper and lower borders are presumed to be adiabatic. The finite difference technique is applied to crack the non-dimensional leading equations. An Alternating Direction Implicit (ADI) procedure is utilized to simulate the vorticity and energy equations. The stream function equation is resolved by using the Successive Over Relaxation (SOR) scheme and the central differencing scheme is used to evaluate the velocity terms. The nature of fluid flow, thermal behaviour, entropy generation and thermal transportation rate are examined graphically for several physical and geometrical constraints. The attained outcomes disclose that there is a dominance of fluid friction in the generation of entropy inside the annulus and the average entropy production is lowest in the case of annular enclosure rather than the rectangular enclosure.