Impacts of finned rotating cylinder on hydrothermal flow of hybrid nanofluids in a vented cavity based on dynamic mesh approach

Abstract

This study aims to explore and enhance the understanding of how finned rotating cylinders impact mixed convection of the hydrothermal flow and heat transfer of hybrid nanofluids in a vented cavity. The significance of this study contributes to the advancement of increasingly efficient and productive thermal control mechanisms in diverse industrial sectors employing rotating cylinders. Simulations employ a dynamic mesh approach to model the flow domain and boundary motion of the rotating bladed cylinder based on the finite volume technique. The presented results underwent a rigorous comparison with existing related works in the open literature. The chosen working fluid is a Newtonian hybrid nanofluid composed of SiO2-Al2O3 suspended in water. Various configurations of cylinder locations and sizes are examined, alongside a broad spectrum of associated variables with certain ranges. These parameters with defined ranges are; Reynolds numbers (2 × 102 ≤ Re ≤ 1 × 103), cylinder radius (0.1 ≤ R≤0.3), cylinder locations (0.25 ≤ δ ≤ 0.75), spinning speeds (− 3 ≤ Ω ≤ 3), and nanoparticle concentrations (0 ≤ φ1 ≤ 0.03 and 0 ≤ φ2 ≤ 0.03). The results indicate significant impacts of Reynolds numbers (Re), Grashof numbers (Gr), cylinder radius (R), location (δ), spinning speed (Ω), and the number of blades on the hydrothermal characteristics. The major finding states that the cylinder radius of 0.3 for Case 5 with five fins provides the greatest enhancement of mixed flow and relatively maximum heat transfer rate. Furthermore, increasing concentrations of nanoparticles (φ) of hybrid nanofluids further improves the thermal performance.