Influence of Groove Type on Friction Coefficient of Wet Friction Clutch Pair

The shape of the groove in the friction plate of a wet friction clutch has an influence on the dynamic friction coefficient of the friction pair. Some suggestions are put forward for the selection of the groove type of brake pads. This study establishes a dynamic friction coefficient calculation model for clutch engagement process considering the asperity and lubricant bearing capacities of the centrifugal force of the oil film. The model is based on the Reynolds equation, average flow model, and Greenwood model. The friction coefficients of different groove shapes were measured using the SAE#2 testing machine. The measured results were compared with theoretical calculations to verify the accuracy of the theoretical model. Under the premise of satisfying the torque transmission condition of the helicopter, the groove type of the wet clutch friction plate should be waffling groove or double arc groove. In this study, some suggestions are put forward for the selection of the groove type of the friction plate of the wet clutch.