Convection heat transfer inside a lid-driven cavity filled with a shear-thinning Herschel–Bulkley fluid

Abstract

The present numerical study, based on the finite volume method, deals with the characterization of flow and heat transfer convection inside a lid-driven square cavity filled with a shear-thinning Herschel–Bulkley fluid. The upper and bottom walls of the enclosure are thermally insulated, while the vertical ones are mobile and differentially heated. The study focuses on the effect of the fluid’s rheological properties, i.e., the fluid’s viscoplasticity (0.50 ≤ Bng ≤ 5000) and the flow index (0.2 ≤ n ≤ 1.0), on both flow and heat transfer within the cavity on one hand and on the modifications involved by the introduction of viscous dissipation (0 ≤ Br ≤ 10) on the other hand. The results show that the increase of the generalized Bingham number leads to the increase of the unyielded regions inside the enclosure. In addition, heat transfer is more pronounced for weak values of the generalized Bingham number and great values of the fluid’s flow index. Viscous dissipation modifies significantly both flow and heat transfer structures, especially for mixed and dominant natural convection. To sum up the obtained results, useful abacuses predicting the heat exchange within the enclosure are given.