The effect of changing magnitude and direction of the magnetic field on the flow and combined convection heat transfer for the nanofluid in concentric/eccentric rotating cylinder annulus

Document Type : Original Article

Authors
Nasrin Shoul 1
Behrad Haghighi 2
Ali Abshahi Pour 1
1 Department of Mechanical Engineering Vali-e-Asr University of Rafsanjan Iran
2 Department of mechanical engineering Vali-e-Asr university of Rafsanjan Iran
10.22077/aec.2023.5952.1017
Abstract
In this research, fluid flow and heat transfer along with free and forced convection for nanofluidIn this research, fluid flow and heat transfer along with free and forced convection for nanofluid (aluminum oxide/water) confined in the space between two concentric and non-concentric cylinders in a horizontal state of infinite length which are at two temperatures have been kept differently, has been investigated in the presence of a magnetic field, with variable magnitude and direction, it has been simulated by Fluent software, and its design and meshing has been done by Gambit software. Forced flow occurs due to the rotation of the outer cold cylinder with a constant angular velocity around the central axis of the two cylinders. In addition, Buzinsk's approximation has been used to calculate the buoyancy forces that arise due to the temperature difference between the two cylinders. The obtained results are presented for a different range of dimensionless numbers (Reynolds, Rayleigh, Hartmann) and volume fraction of nanoparticles. The numerical results show that an increase in the volume fraction and Rayleigh number leads to an increase in heat transfer, and an increase in the Reynolds number leads to its decrease, and also the use of an external magnetic field suppresses the fluid velocity and heat transfer, and these changes are more tangible in the vertical direction.
Keywords
Combined convection
Nanofluid flow
Magnetic field
Non-concentric cylinders