Experimental Performance of a Novel Trochoidal Propeller

In the quest for higher energy efficiency in marine transportation, a promising alternative marine propulsor concept is the trochoidal propeller. The authors have 1) designed and tested a novel trochoidal propeller using a sinusoidal blade pitch function and 2) created a theoretical model to describe the principal physics governing the operation of such propellers. The main results presented herein are measurements of thrust and torque, as well as the calculated hydrodynamic efficiency, for a range of absolute advance coefficients. The performance of the present sinusoidal-pitch trochoidal propeller is compared with prior cross-flow propellers, as well as a representative screw propeller. Although the efficiency of the present sinusoidal-pitch propeller exceeds that of prior cycloidal-pitch trochoidal propellers, it is slightly lower than the efficiencies of the other propellers considered. Model predictions show excellent agreement with the experimental data, which opens possibilities for future investigation and optimization of novel blade pitch motions.