Optimizing heat transfer in laminar channel flow using inclined inverted L-shaped obstacles

This study numerically investigates the influence of obstacle inclination and flow rate on the convective heat transfer performance in a 3-D rectangular channel equipped with periodically arranged inverted L-shaped obstacles. Using the finite element method, simulations were conducted for laminar flow conditions across a range of Reynolds numbers (Re = 20-600) and obstacle inclination angles (30?, 45?, and 60?). Water was used as the working fluid, and thermal enhancement was evaluated using temperature contours, local Nusselt number distributions, and average Nusselt values. Results reveal that increasing both Reynolds number and obstacle inclination significantly enhances thermal performance. The 60? configuration consistently yielded the highest local and average Nusselt numbers, with up to 99.5% improvement over the 30? case at Re = 600. Temperature fields confirmed enhanced vortex formation, mixing, and wall impingement in steeper geometries. This study highlights the potential of obstacle inclination as a passive enhancement technique in compact thermal systems operating under laminar flow conditions.