Some considerations about the effect of grooves on the viscous coupling performances

Abstract

Abstract A viscous coupling transmits torque by viscous shearing of the oil film between one or multiple pairs of discs that are in relative motion one to the other. A viscous coupling uses a viscous fluid as a working medium and performs best in full film lubrication condition. A continuous film of oil must be present at all times between the two surfaces that are in relative motion. Only in this stage, when operating in full film lubrication condition, this coupling can achieve the maximum transmission of torque. This kind of study is of a great importance since this coupling is widely used all around the world in all sorts of applications. In this paper, the effect of grooves on the viscous coupling performances was carried out deeply using a Computational Fluid Dynamics Software. The flow of the fluid film and shear torque between the friction pair are complex and keep changing with the operating conditions, the geometry, the number of grooves, the properties of the working oil and the thickness of the oil film.