Numerical Analysis of Enhanced Forced Convection in Perforated Surface Wavy Plate-Fin Cores

Steady, periodically fully developed forced convection through three-dimensional perforated sinusoidal wavy fin cores with uniform wall temperature is computationally investigated. Constant property airflow (Pr ≈ 0.71) with a Reynolds number range of 50–4000 covering both laminar and turbulent regimes is considered. The computational solutions, validated with in-house experimental data for continuous and perforated wavy fin coupons, highlight the effects of perforation locations (characterized by phase angle β), fin porosity, inter-fin spacing, and corrugation amplitude on the thermal-hydraulic performance of the fins. The local temperature, velocity, and pressure variations, and the corresponding local heat transfer coefficient and friction drag (or the Colburn factor j and Fanning friction factor f) are reported. Fluid flows from the adjacent channels through wavy surface perforations induce secondary flow and interrupt the boundary layer leading to an increase in f and j in both laminar and turbulent regimes. Decrease in corrugation amplitude and inter-fin spacing leads to the suppression of recirculation zones, whereas higher porosity yields increased f and j. Perforated fins nevertheless require less surface area to fulfill a specified heat load condition with a fixed pressure drop as compared to the continuous wavy fins. Furthermore, the perforation location has a noticeable effect on the local heat transfer and flow dynamics and, except for Re < ∼200, wavy fins with perforations at relatively higher phase angle β perform better.