Buoyancy-Driven Flow and Forced Flow of Complex Fluid Within a Triangular Chamber with a Rotating Body

This study investigates mixed convection heat transfer of a non-Newtonian fluid within a finned triangular cavity containing a horizontally oriented, rotating cylinder with a circular cross-section. The cylinder, maintained at a high temperature, rotates at a constant speed, while the cavity walls are kept at a cold temperature. This configuration is significant for applications in cooling technologies and materials processing. Unlike previous studies that primarily focused on simpler geometries, this work uniquely examines the effects of varying blockage ratios in a finned triangular cavity, a less explored configuration. The analysis considers key parameters such as cylinder rotation speed (Re = 1, 5, and 10), thermal buoyancy intensity (Ri = 0, 1, 2, and 3), fluid viscosity (characterized by the power-law index, n=0.6, 1, and 1.6), and blockage ratio (β = 0.12, 0.24, and 0.36). Numerical simulations were performed using the finite volume method to solve the governing equations, with Ostwald’s law modeling the fluid’s rheological properties. Results show that increasing the blockage ratio stabilizes the flow, suppressing counter-rotating regions around the cylinder and reducing the heat transfer rate by more than 30%. Additionally, a decrease in the fluid’s power-law index enhances heat transfer from the hot cylinder. These findings provide valuable insights for optimizing thermal systems.