Novel Physical Insights into the Thermodynamic Irreversibilities Within Dissipative EMHD Fluid Flows Past over a Moving Horizontal Riga Plate in the Coexistence of Wall Suction and Joule Heating Effects: A Comprehensive Numerical Investigation

In the case of an electro-magneto-hydrodynamic actuator, little is known about the thermo-magneto-hydrodynamic irreversibilities arising in the dissipative flows of weakly conducting fluids past over a moving Riga plate. In this study, the electro-magneto-hydrodynamic convective flow features of a viscous electrically conducting fluid over a horizontal Riga plate are deliberated comprehensively by considering the wall suction and Joule heating effects. It is assumed that the permanent magnets are of equal width and mounted alternatively on a plane surface. Due to the electromagnetic proprieties of the Riga plate, the exponentially decaying Grinberg term is included in the momentum conservation equation as a resistive drag force in this investigation. The modeled differential equations were non-dimensionalized and simplified mathematically by utilizing suitable dimensionless variables and adopting admissible physical assumptions. Numerical solutions were established herein by utilizing an efficient algorithm based on the generalized differential quadrature method and the Newton–Raphson iterative technique. It is worth concluding that the presence of the wall suction effect enhances noticeably the heat transfer rate and its thermodynamic irreversibility near the Riga plate, while a reverse feature is depicted with the elevating strengths of the magnetization field.