Computational analysis of fluid flow and convection heat transfer characteristics of multiple heat sink for electrical power stack cooling

• Published in: Applied Thermal Engineering
• Main Author: Azizan N.A.C.; Norazam N.F.; Tijani A.S.
• Format: Article
• Language: English
• Published: Elsevier Ltd 2025
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85214326347&doi=10.1016%2fj.applthermaleng.2025.125426&partnerID=40&md5=92928c08d238d5ef21c5f9caabc95155

This paper investigates thermo-hydraulic performance of new design overlap heat sinks. Design 1 is a heat sink with trapezoidal fillet and symmetrical half-round pins in horizontal arrangement. Design 2 is a heat sink with half parabolic fillet and symmetrical half-round pins in a horizontal arrangement. Each design consists of 0 % overlap ratio (non-overlap), 50 % overlap ratio (partial-overlap) and 100 % overlap ratio (fully-overlap). The Menter's Shear Stress Transport turbulence model (k-ω SST) was used to numerically simulate fluid flow and heat transfer characteristics. The results show that the partial overlap design has the highest Nusseslt number, followed by non-overlap and fully-overlap heatsink. At a velocity of 2 m/s, the performance for non-overlap, partial overlap and fully overlap are 0.45, 0.25 and 0.15, respectively. The deterioration of the performance was due to increase in pressure drop penalty. Design 1 with fully overlap has about 30 % increase in pressure drop compared with design 2. Interestingly the heat transfer coefficient of partial overlap design (Design 1) is about 12 W/m2.K which is about 36.6 % increase in heat transfer coefficient. The findings of this study make several contributions to the current literature through heat transfer enhancement and electrical power stack space minimization. In terms of space minimization, the fully overlap heat sink can be applied in minimizing electrical stack cabinet space, however, for heat transfer characteristics, the partial overlap heat sink has a better performance. The novel fillet profile coupled with the symmetrical half-round pins promotes heat transfer due to increase in heat transfer area. © 2025 Elsevier Ltd