Temperature-dependent shear-thinning Herschel–Bulkley fluid flow by taking into account viscous dissipation

TLDR: In this paper, a numerical analysis of hydrodynamic and thermal characteristics of a shear-thinning Herschel-Bulkley fluid flow within a pipe of a circular cross section, maintained at a uniform wall temperature, is presented.

Abstract: The present numerical study deals with the analysis of hydrodynamic and thermal characteristics of a shear-thinning Herschel–Bulkley fluid flow within a pipe of a circular cross section, maintained at a uniform wall temperature. The governing equations of the studied steady problem are solved using a homemade computer code based on the finite volume method. The paper is focused on the consequences of neglecting the temperature dependency of the fluid’s consistency and/or the viscous dissipation on both pressure drop and heat transfer. The results show, indeed, that neglecting the temperature dependency of the fluid’s viscosity leads to significantly undervalue these parameters, especially when viscous dissipation is also missed. Abacuses depicting the friction factor of Fanning and the Nusselt number variations according to both Brinkman number and dimensionless temperature coefficient are proposed to sum up the study.