A Precision, High Capacity, High Speed, Right Angle Drive Fully Submerged Propulsor Dynamometry System (FSPD)

This paper explains the capabilities of a new right angle drive propeller dynamometry system which has recently been put into service at the Carderock Division of the Naval Surface Warfare Center (CDNSWC). The towing carriage mounted Fully Submerged Propulsor Dynamometer (FSPD) was designed to make precision steady state measurements of propeller thrust and torque while moving through the water at high speeds in the towing basin. Experiments may be performed at various depths and shaft inclination angles. The capabilities introduced by this new instrument will make investigations into many phenomena and the measurement of their effects on propeller performance possible. The FSPD has been used for obtaining the high speed open water performance for the large diameter propulsors used in cavitation experiments at CDNSWC. Experiments have been performed to determine the effects of the variation of propeller depth of submergence and Reynolds Numbers on open water performance. Some preliminary experimental results are presented in this paper.