Numerical Investigation of Mixed-Convection of Water-Graphene Nanofluid in the Existence of Magneto-Hydrodynamic Field and a Rotary Cylinder Inside a Wavy Cavity

In the present investigation, a study about the influence of a rotary cylinder on the MHD mixed-convection of a water-graphene nanofluid into a wavy cavity is performed numerically. The two vertical walls of cavity are adiabatic and the bottom and top wavy walls are assumed to be the hot and cold ones with temperatures of T h and T c , respectively. The rotary cylinder is considered to be adiabatic which rotates in the clock-wise direction. The finite volume numerical manner is utilized to simulate the mixed-convection flow in the cavity. Impacts of several determinant parameters including Hartman number, Grashof number, rotation velocity, and volume fraction of nanoparticles are inspected. The results have shown that by contribution of the rotary cylinder, the hot wavy wall could be cooled faster while by increasing of the rotational velocity to 2000 rpm, Nusselt number enhances up to 2700%, 922%, and 417% for Gr = 10 6 , 10 7 , and 10 8 , respectively in the lack of an external magnetic field. Furthermore, adding of nanoparticle to water as the base fluid fasten the heat transfer rate.