Role of heating configuration and internal heat generation in rotating porous ferroconvection

The onset of thermogravitational ferroconvection in a rotating porous ferrofluid layer is analyzed considering Coriolis effects, magnetic forces, and volumetric heat generation. Momentum transport is described by a Brinkman-extended Darcy model that accounts for viscous diffusion and porous resistance, while rigid paramagnetic boundaries modify the internal magnetic field through their finite magnetic susceptibility. Linear stability analysis leads to a Galerkin eigenvalue problem for the neutral conditions, and for large Prandtl numbers typical of ferrofluids, the instability is stationary. The instability reflects a balance between buoyancy and thermomagnetic driving, modulated by rotation and porous resistance. Coriolis-induced deflection suppresses vertical motion and limits convective transport, an effect reinforced by porous drag. In contrast, magnetisation gradients generate a Kelvin body force that augments buoyancy and enhances convective heat transport, while internal heat generation strengthens thermal gradients. Boundary magnetic susceptibility alters the internal field distribution and weakens the effective magnetic forcing, contributing to stabilisation. Thermal forcing asymmetry remains decisive: heating from above suppresses overturning, whereas heating from below promotes buoyant plumes and earlier transition. The results reflect this interplay, with internal heating favouring smaller-scale convection and stronger rotational and permeability constraints promoting broader patterns. Classical limits are recovered, confirming the consistency of the formulation.