Context. Observations indicate that the ‘quiet’ solar photosphere outside active regions contains considerable amounts of magnetic energy and magnetic flux, with mixed polarity on small scales. The origin of this flux is unclear. Aims. We test whether local dynamo action of the near-surface convection (granulation) can generate a significant contribution to the observed magnetic flux. Methods. ...

flow field and heat transfer of a nanofluid, whose non-newtonian behavior has been demonstrated in the laboratory, in a square enclosure have been numerically modeled and investigated. to estimate the viscosity of nanofluid, experimental data of hong and kim, 2012 have been used, and a new model has been proposed. finally, the obtained results have been compared to those of newtonian behavior. ...

in this paper the effect of using various models for conductivity and viscosity considering brownian motion of nanoparticles is investigated. this study is numerically conducted inside a cavity full of water-al2o3 nanofluid at the case of mixed convection heat transfer. the effect of some parameters such as the nanoparticle volume fraction, rayleigh, richardson and reynolds numbers has been exa...

The nonlinear two-dimensional forced-convection boundary-layer magneto hydrodynamic MHD incompressible flow of nanofluid over a horizontal stretching flat plate with variable magnetic field including the viscous dissipation effect is solved using the homotopy perturbation method HPM . In the present work, our results of the HPM are compared with the results of simulation using the finite differ...

This study investigated heat transfer in magnetohydrodynamic (MHD) mixed convection flow of ferrofluid along a vertical channel. The channel with non-uniform wall temperatures was taken in a vertical direction with transverse magnetic field. Water with nanoparticles of magnetite (Fe3O4) was selected as a conventional base fluid. In addition, non-magnetic (Al2O3) aluminium oxide nanoparticles we...

The steady two-dimensional MHD heat transfer mixed convection flow of a viscous incompressible fluid near a stretching permeable sheet in presence of a uniform magnetic field with heat generation is considered when the buoyancy force assists or opposes the flow. The equations governing the flow and temperature fields are reduced to a system of coupled non-linear ordinary differential equations....

Energy transfer in mixed convection unsteady magnetohydrodynamic (MHD) flow of an incompressible nanofluid inside a channel filled with saturated porous medium is investigated. The channel with non-uniform walls temperature is taken in a vertical direction under the influence of a transverse magnetic field. Based on the physical boundary conditions, three different flow situations are discussed...

[1] This paper describes the coupling of BATS-R-US (Block Adaptive Tree Solar-wind Roe-type Upwind Scheme), a magnetohydrodynamics (MHD) code representing the Earth’s global magnetosphere and its coupling to the ionosphere and solar wind, and the Rice Convection Model (RCM), which represents the inner magnetosphere and its coupling to the ionosphere. The MHD code provides a time-evolving magnet...

Abstract The magnetohydrodynamic (MHD) mixed convection of heat and mass transfer is carried out using finite difference method applied inside a tilted porous cavity saturated with hybrid nanofluid due to the presence double-moving lid sources. In contrast earlier research, various effects which are recognized by generation in local thermal non-equilibrium case at extended Brinkman Darcy model ...