The purpose of this research program was to develop a vane type hydraulic starter motor for aircraft, high-speed, auxiliary power units. The goals were to achieve a starter cutoff speed of 50,000 RPM and an inlet pressure capability of 8000 PSIG maximum using MIL-H-5606 hydraulic oil as the working fluid. A balanced, three element, single eccentric vane motor has been designed and proved capable of operation at 30,000 RPM and 3000 PSIG. The 0.145 cu in./rev. prototype motor had a 72% torque efficiency at the noted conditions. Although the design goals proved unattainable, the unique vane motor design demonstrated that high speed hydraulic motor operation is feasible. The inability of the vane tip/cam ring interface to survive the high vane tip surface speed and loading represents the major problem that must be eliminated if the goal conditions are to be achieved. Use of highly wear resistant vane and cam ring materials did not provide a solution to this difficult lubrication problem. The vane motor was not evaluated at the projected thermal extremes (-65 F. to +130 F.) and the proposed hydraulic starter system demonstration was not conducted when the operational limits were found to be far less than the original starter motor objectives. (Author)
High Speed Hydraulic Starter Motor for Aircraft Auxiliary Power Unit
1976
76 pages
Report
No indication
English
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