Nanofluid (H 2 O-Al 2 O 3 /CuO) flow over a heated square cylinder near a wall under the incident of Couette flow

Abstract

A long heated cylinder was placed near a cold wall under the incident of a Couette flow. The conventional fluid was chosen as water (H 2 O). The nanoparticle materials were selected as Al 2 O 3 and CuO. The governing Navier-Stokes and energy equations were solved numerically through a finite volume method on a staggered grid system using QUICK scheme for convective terms and SIMPLE algorithm. The dependencies of hydrodynamic and heat transfer characteristics of the cylinder on non-dimensional parameters governing the nanofluids (Particle concentrations (φ), diameter (d np ), and particle materials) and the fluid flow (Peclet number Pe and gap height ratio L) were explored here. The shifting of the front stagnation point due to the addition of nanoparticles in the base fluid was investigated. A comparison between the heat transfer enhancement (N uM ) of the cylinder and its drag coefficient’s (C D ) increment/reduction was made by presenting their ratio Nu M /CD. The least square method was applied to the numerical results to propose Nu M = Nu M (Pe) and Nu M = Nu M (L).