NACA Airfoils as Proposal for Heat Sink Fins: Optimization Investigation

This work presents a simulation analysis using a multi-objective evolutionary algorithm for the thermo-hydraulic behavior of staggered heat sinks whose fins have NACA 0040 airfoil profile. The results were compared with a conventional pin fin heat sink with a circular profile. This study searched for the best thermo-hydraulic performance by translational and rotational positioning of the fins. It is worth mentioning that this work was carried out in two stages. In the first stage, the thermo-hydraulic behavior of the heat sink was studied moving the location of the upper array above the X-axis from −2.25 to 2.25 mm and above the Y-axis from −1.55 to 1.275 mm. The second stage examined the effects of fin rotation considering the results found in stage 1. However, in this second stage, both arrays were free to rotate. For the upper array, the rotation range was −25° to 25° and for the lower array the rotation range was −15° to 15°. It is worth mentioning that both stages were analyzed for a single Reynolds (Re) number value of 13,000. The optimization results using the multi-objective evolutionary algorithm showed that compared to a NACA 0040 heat sink with fixed, unrotated original configuration (C0), the NACA 0040 heat sink with any Position Configuration (PC) did not significantly improve the heat transfer. Then, the results found in the second stage showed that the effect of the rotation of both sets did not influence the increase in pressure drop. However, it was found that with the Optimal Position and Rotation Configuration (PRCoptimal), which is the optimized array from Stage 1 (position) then optimized by rotation, there is a slightly higher Performance Evaluation Criterion (PEC) compared to the original C0 configuration by 7%. Finally, the proposed NACA 0040 heat sink with the optimal rotation and position setting (PRCoptimal) was found to have a PEC of 9% compared to a conventional pin fin heat sink.