Shape effect of nanoparticles and entropy generation analysis for magnetohydrodynamic flow of Al₂O₃-Cu(H₂1O) hybrid nanomaterial under the influence of Hall current

The purpose of the present study is to examine the swirling flow problem for hybrid nanoliquid (Al₂O₃-Cu(H₂O) over a rotating disk under the influence of Hall current and a convectively heated surface. The flow model is developed using the well-known Tiwari and Das nanofluid model. Joule and viscous dissipations produced in the presence of magnetic field and viscosity, respectively, are accounted in the energy equation. Mathematical modeling of the total entropy production rate is also presented. The nonlinear partial differential equations, which describe the flow phenomenon, are metamorphosed by transformation into the non-dimensional ordinary differential equations (ODEs). The bvp4c technique is then employed in conjunction with the boundary conditions to solve the constructed ODEs. The influences of the relevant flow characteristics on entropy production, flow field (axial and tangential velocity), Bejan number and temperature profiles are depicted graphically. In addition, the effect of shape factor of scattered nanoparticles, such as Al₂O₃ and Cu, on the surface drag force and rate of heat transference is measured and tabulated. The results show that as the Hall parameter rises, the axial fluid velocity rises as well. Entropy generation improves with either the increase in magnetic parameter or Brinkman number. (author)