Numerical investigation on the influence of installation angle of inclined interrupted fins heat sink on heat dissipation performance

Abstract

Numerical simulations of a symmetric array of inclined fins heat sink under natural convection had been carried out using the ANSYS icepak to solve the complete Navier-Stokes equation and the energy equation in the current study. The effects of fin height (20 mm ≤ H ≤ 40 mm) and heat sink installation angle (–45° ≤ φ  ≤ 30°) were analyzed. The work fluid was the air. The results showed that when the input power was constant, as the fin height increased, the heat transfer performance improved. There was no better heat transfer performance than the case of fin height was 40 mm, of which the corresponding heat transfer resistance was also almost the lowest. Compared with H = 20 mm and H = 30 mm, the case of H = 40 mm can reduce the average substrate temperature by 5%−10%. The installation angle greatly affected the heat transfer performance of the heat sink. Compared with the negative installation angle, the positive installation angle showed stronger inhibition on the heat dissipation. The installation angle of −15° showed the highest heat transfer coefficient, which could improve the heat transfer coefficient by about 7%. The Nusselt number (Nu) was found to increase approximately linearly with the Rayleigh number (Ra) in the range of 8.5 × 106 ∼ 1.64 × 107. A correlation between Nu and Ra, the geometric parameters of fin arrangement and the dimensionless correlations related to the heat sink installation angle were obtained. Highlights A new type of fin heat sink was proposed to improve heat sink performance. The heat sink installation angles was studied with the best angle found. The correlation formula related to the installation angle was obtained.