Research Status and Outlook for Oil Film Power Transmission Between Friction Pairs

Using viscosity of fluid between friction pair to transmit power is called the Hydro-viscous Drive (HVD), which has obvious energy-saving effects on soft start and speed regulation. In this review, we introduce the basic principle of HVD and HVD production development, and emphasize the potential of ever increasing power of HVD in future industrial applications. The current status of research in HVD is described which includes the improvements in the understanding of transmission mechanism of the oil film between the friction pair and in the development of intelligent control systems for HVD based devices. In particular, four aspects of HVD need to be further researched, which include the development of higher power HVD devices, new friction materials, multi-friction pair coupling issues and new intelligent control systems. The goal of this review is to attract the attention of researchers to these fertile areas of investigations related to HVD; and to provide an overview about the oil film transmission between friction pair by addressing recent patents and scholarly articles on the subject of design, control and application of such systems.