Repercussions of Local Thermal Non-Equilibrium in Conjunction with Uniform/Non-Uniform Thermal Gradients and Magnetic Flux on the Onset of Darcy-Rayleigh-Benard-Marangoni Convection in a Composite Layer

Abstract

Repercussions of uniform/non-uniform thermal gradients such as linear, parabolic, inverted parabolic, piecewise linear gradient heated from below (PLHB), piecewise linear gradient cooled from above (PLCA) and step function (SF) thermal gradients in conjunction with magnetic flux on the onset of Darcy-Rayleigh-Benard-Marangoni (DRBMM) convection in a composite layer involving incompressible fluid and holding horizontal adiabatic boundaries, rigid beneath the porous layer and free aloft the fluid layer is performed apropos to Local Thermal Non-Equilibrium (LTNE). Regular Perturbation method is exercised to attain the analytical solution of the acquired problem. For all the six thermal gradients, (i) The strength of variables such as solid phase thermal expansion ratio, solid phase thermal diffusivity ratio and inter-phase thermal diffusivity ratio that boosts LTNE are analysed and (ii) The influence of change in measure of physical quantities viz. fluid phase thermal expansion ratio, fluid phase thermal diffusivity ratio, Chandrasekhar number and Marangoni number are studied.