MHD free convection in a partially open wavy porous cavity filled with nanofluid

Abstract

Background

The investigations of natural convection in open cavities admit an indispensable insight to the research community, and many research articles are published in this area as the wide range of applications in industries. We focus on investigating free convection in a partially open square cavity; the use of a wavy cold wall will have a larger surface than a straight cold side wall for a fixed distance.

Methods

This numerical investigation is aimed at MHD free convection in a partially open wavy porous cavity filled with nanofluid. The cavity is positioned vertically, and the wavy cavity wall on the right side maintains a constant low temperature. The top wall is partially opened, the magnetic field is applied horizontally from the left wall, and the bottom and top walls are adiabatic. The solutions of dimensionless governing equations are computed by the finite difference method (FDM) for a wide range of governing parameters: nanoparticles volume fraction $(0\le \varphi \le 0.05),$ Hartmann number $(0\le Ha\le {10}^2),$ Rayleigh–Darcy number $(10\le Ra\le {10}^3),$ the position of a partial opening $(d=1/6,1/2,5/6),$ length of the opening $(ϵ=1/3),$ undulations number per unit length $(1\le N\le 5),$ and dimensionless wave amplitude $(0.05\le a\le 0.25).$

Significant findings

Obtained results reveal that overall convection is reduced as the nanoparticle volume fraction or Hartmann number augments, and the effect of the position of the opening is minor at a higher value of the Hartmann number; also, the waviness is an increasing factor for the average Nusselt number.

Keywords:

• Finite difference method
• free convection
• heat source
• magnetohydrodynamics
• porous media
• wavy cavity

Disclosure statement

The contributors affirm that they have no known financial or interpersonal conflicts that would have seemed to have an influence on the findings presented in this study.

Additional information

Funding

The corresponding author received the fund from DST(SERB) under Project No: MTR/2021/000197 DST(SERB) 306/2021-2022 as a part of this piece of work.