Regular Article

CFD simulation of air effect on flow field characteristics of hydro-viscous clutch with constant speed difference

¹ School of Mechanical Engineering, Jiangsu University, Zhenjiang, PR China
² The State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, PR China
³ The Institute of Mechanical and Electrical Engineering, Hanoi University of Mining and Geology, Hanoi, Vietnam

^* e-mail: xiefangwei@ujs.edu.cn

Received: 19 January 2018
Accepted: 19 June 2018

Abstract

The purpose of this paper is to study the air effects on transmission characteristics of hydro-viscous clutch and reveal the distribution law of the flow field of the oil film. The computational-fluid-dynamics (CFD) simulation model of oil film with radial oil grooves between friction pairs is taken as the study object. Considering the air effects, the pressure field, two-phase distribution, transmission torque and temperature field of the oil film are analyzed comparatively by using the CFD technology. The results show that the presence of air changes the pressure and temperature distributions of the oil film. With increase of the absolute rotational speed, the air volume fraction increases and the radius value of the air-liquid boundary decreases under condition of constant speed difference, which makes the coverage rate of the oil film on the surface of the friction disks reduce and the transmission torque of the oil film decrease. These simulation results are attributed to the study of hydro-viscous-drive and its applications. This paper also can provide a theoretical basis for the mechanism of power transmission through oil film in the presence of air effects.