Numerical simulation research on effect of oil groove forms on thermal behavior of friction pair in hydro-viscous clutch

Purpose – The purpose of this paper is to study the influence of different cross-sectional shapes (rectangular, trapezoidal, oval and triangular) and layout forms of oil grooves (radial, circumferential, inclined, compound, helical and double-helical), and determine the optimal section shape and layout form of oil grooves on the temperature field. Design/methodology/approach – Heat conduction theory model was established based on startup characteristics and friction heat principle of hydro-viscous clutch (HVC), and then the theoretical expression of angular velocity of the friction pair and control pressure were deduced, and the heat flux and its distribution on friction disk and separator disk were calculated. Finally, the finite element method was used to solve the temperature field of the friction pair. Findings – The studies show that the circumferential oil groove got the highest temperature, and on the surface of all other structures, hot spots appear with different sizes and temperatures, and the maximum temperature difference in the friction zone is about 3°C, and in the oil groove zone is about 16°C, wherein the compound oil groove has the lowest average temperature. This research shows that the compound oil groove with rectangular cross-section is the best choice for the friction pair. Originality/value – In this paper, it was found that the compound oil groove with rectangular cross-section is the best choice for the friction pair, and it provided a favorable theory reference and technical support for the structural design of the friction pair and optimized design of the high-power HVC.