Inspection of unsteady buoyancy and stagnation point flow incorporated by Ag-TiO2 hybrid nanoparticles towards a spinning disk with Hall effects

Abstract

The viscous flow across a rotating body is an emblematic phenomenon in many production processes, particularly in systems involving rotating disks. This study discusses the impact of buoyancy force and Hall effects on the time dependent stagnation point flow of Ag-TiO2/water hybrid nanofluid (HNF) flow over a rotating disk together. The Ag-TiO2/water HNF flow is investigated for two cases: assisting and opposing flow. Utilizing the appropriate similarity transformations, the partial differential equations (PDEs) representing the heat transfer problem are altered to ordinary differential equations (ODEs). The governing equations are solved numerically employing the “bvp4c function in MATLAB”. The current results are validated by comparison with the available literature and a very close precision is obtained. The influence of the primary relevant parameters on the properties of flow, and heat transmission rate is depicted graphically. The azimuthal and radial velocities of HNF flow are greater for assisting flow. The thermal profile of Ag-TiO2/water HNF flow is greater for opposing flow. The greater values of the Reynolds number surge the HT rate on the surface. The outcomes of this study will be useful in many fields that utilize applications of rotating disk systems such as rotor-stator systems, power generators, geothermal extraction, computer storage devices, engines in gas turbines, brakes, gears, and flywheels.

Keywords

• Buoyancy forces
• Spinning disks
• Hybrid nanofluid
• Unsteady flow
• Heat transfer
• Hall current