2. Mixed Convection and Entropy Generation Analysis of CNT-Water Nanofluid in a Square Cavity with Cylinders and Flow Deflectors
Authors - Hashnayne Ahmed*, Shashanka Biswas, Farzana Akter Tina
July 2024 - arXiv Link
Abstract
This study explores the mixed convection of CNT-water nanofluid within a square cavity containing heated cylinders under the influence of a magnetic field, focusing on three geometric configurations: a single heated cylinder, two heated cylinders, and two heated cylinders with a flow deflector. The impact of various parameters, including Reynolds number (Re), Richardson number (Ri), Hartmann number (Ha), wavy wall peaks (n), nanoparticle volume fraction ({\phi}), Hartmann angle ({\gamma}), rotational speed ({\omega}), and inclination angle ({\alpha}), on thermal and fluid dynamic behaviors is analyzed. Results reveal that MWCNT nanofluids consistently achieve higher Nusselt numbers than SWCNT nanofluids, indicating superior heat transfer capabilities. Introducing a second cylinder and a flow deflector enhances thermal interactions, while increasing Ha stabilizes the flow, improving thermal performance. Wavy wall peaks further enhance fluid mixing and heat transfer efficiency. Additionally, SWCNT nanofluids exhibit higher Bejan numbers, indicating a greater dominance of thermal entropy generation over fluid friction. These findings provide valuable insights for optimizing thermal management systems in engineering applications, highlighting the importance of selecting appropriate nanofluids, geometric configurations, and magnetic field parameters to achieve optimal thermal performance and fluid stability.
1. Mixed Convection Heat Transfer and Flow of Al2O3-Water Nanofluid in a Square Enclosure with Heated Obstacles and Varied Boundary Conditions
Authors - Hashnayne Ahmed*, Chinmayee Podder
January 2024 - arXiv Link
Abstract
This paper studies the effects of mixed convection fluid motion and heat transmission of Al2O3-Water nanofluid in a square enclosure including two heated obstacles, with temperature and nanoparticle concentration being determined by the thermal conductivity and effective viscosity. The parametric observations of Richardson number, Reynolds number, cylinder rotating speed, and cavity inclination angles are investigated in the range of 0.1 \leq Ri \leq 10, 1 \leq Re \leq 125, 1 \leq \omega \leq 25, and 0^\degree \leq \gamma \leq 60^\degree respectively on the thermal environment and flow arrangement inside the cavitation field. Adding nanoparticles to the base fluid enhances the heat transfer rate for both obstacles and all ranges of the parameters. The influence of wavy walls, changes in the nanofluid, and distinct positional effects also impact the flow characteristics and heat transfer process.