Poiseuille–Couette flow of a hybrid nanofluid in a vertical channel: Mixed magneto-convection

The study of mutual interaction between flow and external magnetic field, as well as the influence of temperature on the motion, is crucial for new classes of materials involved in nanotechnologies. This paper considers a very common situation where a hybrid nanofluid fills a vertical plane channel with a moving wall. Since the nanofluid is Boussinesquian the flow is induced by the buoyancy and Lorentz forces together with a constant pressure gradient. This problem has many industrial applications so that it is of relevant interest. Using a steady and laminar flow, an exact solution for the ODEs which govern the motion has been found. This is the first time an analytical solution is developed for the problem here considered. Analytical expressions for velocity profile and magnetic field are exhibited graphically. Effect of parameters on the flow characteristics has been discussed also in the case of some real hybrid nanofluids (H2O with Al2O3 and Cu, H2O with Ag and MgO, C2H6O2 with TiO2 and Fe3O4). We also find that the presence of two different types of particles determines an increase in the velocity of the nanofluid in accordance with experimental studies. As usual the presence of the external magnetic field causes a decrease in the velocity. Finally, the reverse flow phenomenon is discussed.