Affiliation:
1. Institute of Low‐Carbon Energy and Artificial Environment Construction, School of Environment and Energy Engineering Anhui Jianzhu University Hefei China
Abstract
ABSTRACTPorous‐fluid systems, which consist of a porous medium structure and a flow passing over it, play a crucial role in aerospace engineering and heat exchanger design. This study aims to investigate the influence of geometric parameters and porous medium properties on flow and heat transfer characteristics around a porous diamond‐shaped cylinder. A cylinder with variable apex angles (30° ≤ θ ≤ 150°) is numerically analyzed in a two‐dimensional channel using the finite element method (FEM). The effect of Darcy number (10−5 ≤ Da ≤ 10−2), Reynolds number (10 ≤ Re ≤ 40), and the presence of heat source in the porous region are systematically analyzed. Flow visualization based on the Q criterion highlights regions where vorticity dominates over the strain rate, providing insight into vortex formation mechanisms. Results show that under specific conditions, increasing the apex angle (θ) from 30° to 150° leads to a 166% increase in the drag coefficient (Cd), highlighting the significant impact of geometry on flow resistance. For the cases with an internal heat source, the mean Nusselt number (Nu) increases with decreasing Darcy number (Da), suggesting improved heat transfer performance. Specifically, at Re = 40, reducing Da from 10−2 to 10−5 results in an 18.5% to 28.8% enhancement to Nu. Furthermore, this study proposes a new correlation for the drag coefficient (Cd) and Nusselt number (Nu) derived from the present simulation results. This correlation is established based on the Reynolds number (Re), Darcy number (Da), and apex angle (θ). The purpose is offering insights into optimizing porous media configurations in aerospace aerodynamics and microchannel heat exchanger designs.