Three-dimensional assessment of convective heat transfer in perforated cubic obstacles arranged in a staggered pattern under laminar flows

This study presents an investigation into forced convection within laminar fluid flow through a configuration consisting of two heated cubic obstacles with circular perforations, arranged in a staggered pattern on a horizontal plate. The research addresses the critical challenge of enhancing heat transfer in such configurations by examining the influence of variations in streamwise distance (L) and spanwise distance (m) on thermal performance. Employing the finite-volume method, simulations were conducted across a range of parameters: L from 1 to 2 times the obstacle height (H), m from 1/2 to 2 times H, Reynolds numbers (Re) between 102 and 3 × 102, and perforation diameter ratios (D/H) of 0.42 and 0.88. The findings reveal that the Nusselt number (Nu) exhibits significant variation with changes in L/H for solid obstacles, while this effect diminishes for perforated obstacles, particularly at a D/H ratio of 0.88. For the first obstacle, optimal heat transfer is achieved with a streamwise distance equal to H for solid obstacles, whereas no notable differences are observed between the arrangements of perforated models. Notably, perforated obstacles with the maximum D/H ratio exhibit a Nu increase of up to 30% compared to solid obstacles. For the second obstacle, the optimal configuration across all types involves a streamwise distance of H and a spanwise distance of 2H, leading to a 37.4% increase in Nu for large-diameter perforated obstacles compared to solid ones. Overall, the staggered arrangement of perforated obstacles outperforms the tandem arrangement, enhancing heat transfer by up to 43.52% for the first obstacle, 109% for the second obstacle, and 48% for the entire system. This study introduces novel insights into the impact of perforation and obstacle arrangement on heat transfer, demonstrating that staggered arrangements and larger perforation diameters significantly enhance heat transfer compared to solid obstacles, thereby advancing the understanding of convective heat transfer in such setups.