Free convection of Ostwald-de Waele fluid within square enclosure equipped with heat-generating circular solid: MRT-LBM simulation

Abstract

Non-Newtonian fluids are frequently present in many natural phenomena and industrial processes. This research focuses on free convection of Ostwald-de Waele fluid in a square enclosure equipped with a conducting circular body of constant internal volumetric heat flux.

The multiple-relaxation-time lattice Boltzmann approach is used for the numerical simulations of this physical problem. The 2-dimensional 9-discrete velocity (D2Q9) model is applied to the hydrodynamic field and the 2-dimensional 5-discrete velocity (D2Q5) model is used to thermal field. The bounce-back condition coupled with the quadratic interpolation is employed at circular boundaries.

The results show that the increase in the volumetric heat generation reverses, partially or completely, the direction of heat transfer on the hot left wall. Moreover, the employment of a dilatant fluid instead of pseudoplastic and Newtonian fluids leads to an increase in the maximum temperature in the case of a heat-generating obstacle