Entropy generation analysis in magnetohydrodynamic Sisko nanofluid flow with chemical reaction and convective boundary conditions

The main emphasis of the present study is to analyze the novel feature of entropy generation in the flow and heat transfer of Sisko nanofluid over a stretching sheet in the presence of the magnetic field, chemical reaction, and convective boundary conditions. Buongiorno's nanofluid model is used to consider the effect of Brownian diffusion and thermophoresis. The governing Sisko nanofluid flow equations comprising the momentum, nanoparticle volume fraction, and energy are reduced to nonlinear differential equations by utilizing appropriate similarity variables. The numerical solution of nonlinear coupled differential equations is obtained using the finite difference scheme in combination with the quasilinearization technique. The impact of different physical parameters on velocity, nanoparticle volume fraction, and temperature is presented graphically. The variation in entropy generation and Bejan number with different pertinent parameters that characterize the entropy generation phenomenon for the flow of Sisko nanofluid is discussed. The obtained results indicate that the entropy generation enhances with an increase in the magnetic parameter, Brinkman number, and thermal Biot number while reduces with the Sisko material parameter. Moreover, the behavior of mass and heat transfer rates is displayed through the Brownian diffusion parameter and thermophoresis parameter. The analysis of entropy generation minimization has crucial applications in the industrial heat transfer problems, solar heat exchanger, turbomachinery designing, LED-based spotlights, designing of air-cooled gas turbine blades, cooling in nuclear fuel rods, rotating reactors, in chillers, air separators, and so forth. Furthermore, entropy generation with MHD flow has applications in MHD generators, nuclear reactors, flow meters, micropumps, power plants, and so forth.