Exact analysis for the effect of heat transfer on MHD and radiation Marangoni boundary layer nanofluid flow past a surface embedded in a porous medium

In the presence of a magnetic field, thermal radiation and with suction/injection, Marangoni boundary layer flow past a surface embedded in a porous medium saturated by a water based nanofluid containing two different types of nanoparticles, namely Copper and Titanium dioxide, has been studied. Exact solutions of the resulted equations were solved using a new approach via Laplace transform. Influence of the velocity profile and temperature distribution for the present nanofluids was investigated under effect of the involved parameters. It was found that the velocities of the two investigated nanoparticles decrease significantly with an increase in the solid volume fraction. In addition, the effective electrical conductivity parameter is mandatory and should be taken into account on applying the magnetic field; otherwise a spurious physical sight is to be gained. As expected, the magnetic parameter decelerates the fluid velocity and increases its temperature, as well, for all nanoparticles considered and for all investigated cases of the suction/injection parameter, the temperature profiles increase as radiation parameter increases. Further, the fluid suction decreases the fluid velocity and, therefore, thickness of the hydrodynamic boundary layer, regarding, the fluid temperature and thermal boundary layer decreases as well. However, fluid injection produces the opposite effect. (C) 2015 Elsevier B.V. All rights reserved.