Free convective heat transfer with hall effects, heat absorption and chemical reaction over an accelerated moving plate in a rotating system

The unsteady MHD free convective heat and mass transfer flow of an electrically conducting, viscous and incompressible fluid over an accelerated moving vertical plate in the presence of heat absorption and chemical reaction with ramped temperature and ramped surface concentration through a porous medium in a rotating system is studied, taking Hall effects into account. The governing equations are solved analytically with the help of Laplace transform technique. The unified closed-form expressions are obtained for fluid velocity, fluid temperature, species concentration, skin friction, Nusselt number and Sherwood numbers. The effects of various parameters on fluid velocity, fluid temperature and species concentration are discussed by graphs whereas numerical values of skin friction, Nusselt and Sherwood numbers are presented in tabular form for different values of pertinent flow parameters. The numerical results are also compared with free convective flow near ramped temperature plate with ramped surface concentration with the corresponding flow near isothermal plate with uniform surface concentration. •Magnetic field, Hall current, rotation and chemical reaction play vital role on flow field.•Hall current tends to accelerate secondary fluid velocity in the boundary layer region.•Rotation tends to retard primary fluid velocity throughout the boundary layer region.•Rotation and chemical reaction tend to enhance primary skin friction.•Solutal buoyancy force and permeability of medium reduce primary skin friction.