Theory and Validation of Microscopic Contact Model in the Cylinder Block/Valve Plate of Electro-Hydrostatic Module

With the advancement of the aerospace sector, Electro-Hydro static Actuators (EHAs) have gained extensive utilization in aircraft hydraulic systems. The enhanced performance requirements of aircraft have necessitated higher power density and reliability. Consequently, the development of highly compact cohousing Electro-Hydrostatic Module (EHM) has emerged as a pivotal technology. The lubrication interface of EHM plays a crucial role in determining their performance and service life, with the cylinder block/valve plate interface serving as a critical friction interface. In this research, a microscopic contact model is established for the key frictional interface. By combining the viscous friction model based on Reynolds lubrication theory with simulated frictional experimental measurements of the cylinder block/mating disk, the boundary/mixed friction characteristics of the key frictional interface are observed and characterized. This study offers theoretical support for future structural optimization of EHMs, thereby contributing to the field of research.