Abstract
Design of wave energy devices to withstand extreme conditions is a major challenge in wave energy development. Oscillating body devices use relative motion between the bodies to harness the energy though the motion limitation is necessary due to the motion restrictions of the power take off (PTO) mechanisms. This paper focuses on the development of an axial piston pump, which is an integral part of a new hydraulic PTO system that does not need motion restrictions. Since the axial piston pump rotates at relatively slow speed than typical speeds, the effect of lubrication at the motion transfer parts (mainly between swash plate and the slipper bearing) is the key focus of this study. Conventional grove design of the slipper bearing and proposed pocket design were studied and compared using analytical and CFD methods. It is found that, at very slow speeds, the new pocket design shows higher ability to maintain self-balancing on the lubrication layer than that of the conventional slipper bearing.
Hence, new design has prospective for further development to enhance the lubrication ability at very slow speeds suitable for wave energy applications.