A narrative loom of hybrid nanofluid-filled wavy walled tilted porous enclosure imposing a partially active magnetic field. (1st March 2022)

• Record Type: Journal Article
• Authors: Biswas, Nirmalendu; Mondal, Milan K.; Mandal, Dipak Kumar; Manna, Nirmal K.; Gorla, Rama Subba Reddy; Chamkha, Ali J.
• Is Part Of: International journal of mechanical sciences. Volume 217(2022)
• Publication Date: 2022-03-01
• Subjects: Wavy oblique enclosure -- Porous substance -- Hybrid nanofluid -- Magnetohydrodynamics -- Regression analysis; Mechanical engineering -- Periodicals; Génie mécanique -- Périodiques; Mechanical engineering; Maschinenbau; Mechanik; Zeitschrift; Periodicals; 621.05
• DOI: 10.1016/j.ijmecsci.2021.107028
• Languages: English
• ISSNs: 0020-7403

Abstract

Highlights: The present work addresses the impact of partially active magnetic fields on the enhanced thermal performance of hybrid nanofluid (Cu–Al2 O3 –H2 O) filled a porous oblique-wavy enclosure heated partially. A partially active magnetic field can be used as an effective means to control local flow-fields and heat transfer that is found ∼13.97% less compared to that of the whole-domain magnetic field case. The variations in the width of the partial magnetic field, heater length are also analyzed exhaustively. The magnetic field's intensity, porosity, permeability, and the nanoparticles' volume fraction are used to analyze thermo-fluid flow aspects extensively. The use of a wavy wall enhances heat transfer up to ∼22.16% compared to a plain vertical wall. Abstract: Improved controllability along with enhanced thermal performance in modern thermal devices could be achieved using the combination of partial magnetic fields and hybrid nanofluid flow. The present attempt demonstrates the impact of partially active magnetic fields on the enhanced thermal performance of hybrid nanofluid (Cu–Al2 O3 –H2 O) flow in an oblique wavy porous enclosure. The enclosure is partially heated from the bottom and cooled through its wavy sides and suffers from a partially active magnetic field normal to the sidewalls. The transport equations involving complex wavy walls, localized thermal gradient, porous substance, hybrid nanofluid, partial magnetic fields are solved by the finite volume approach numerically using a written FORTRAN code. The effectiveness of the novel implementation of a partial magnetic field is examined rigorously for wide ranges of variations of active heating length ( Lh ), active width of the partial magnetic field ( Wb ) and its positions, magnetic field strength (Ha), the inclination of the cavity ( γ ), Darcy-Rayleigh number (Ram ), Darcy number (Da), and hybrid nanoparticles concentration ( ζ ) additionally applying no and whole-domain magnetic field. The correlation for the average Nusselt number is derived. Finally, the results conclude that the presence of complex wavy walls enhances the heat transfer of ∼22.16% compared to a plain vertical wall; however, the strength of circulation drops. A partially active magnetic field can be utilized as an effective means to control field variables with a lesser reduction in heat transfer (∼13.97%) compared to the whole domain magnetic field. The middle-centered partial magnetic field offers a significant impact on the overall thermal behavior depending on the active width and intensity of the magnetic field, active heating length, and all other involved parameters. Tilting of the cavity reduces the heat transfer rate. Graphical abstract: Image, graphical abstract