Hall effect on MHD transient free convection flow of chemically reactive Casson fluid with heat source/sink past an infinite vertical cylinder

Abstract

This article presents an analytical investigation of the effect of Hall current, magnetic field, and chemical reaction on an unsteady MHD transient free convection heat and mass transfer flow of viscous incompressible, electrically conducting Casson fluid past an infinite vertical cylinder subject to heat source and sink. Closed-form solutions are obtained by employing Laplace transform and inverted using Mellin-Fourier integral and presented them in terms of Bessel functions and modified Bessel functions. To get an insight into the model, we have depicted the graphs of velocity, temperature and concentration profiles for various values of the pertinent flow parameters. The values of Sherwood number, Nusselt number, and skin friction are calculated and presented in the tabular form. Further, we have also considered a special case and investigate the velocity profiles of the Newtonian fluid for both heat source and sink as the Casson parameter α → ∞. From the investigation, it is perceived that with an increase in the values of chemical reaction parameters the species concentration and the velocity of the Casson fluid get reduced while its reverse trend has been observed on Sherwood number and skin friction. With an increase in the Prandtl number the fluid temperature decreases whereas, the Nusselt number increases. A crossing over point is observed in velocity distribution for the Hall current parameter. This fluid flow model will be applicable in geophysics, mining industry, chemical and biomedical engineering such as underground energy system, electromagnetic material production, and automotive fuel level indication, etc.