On the Improvement of Propulsive Peformance of a Ship by the Stators behind the Propeller

Abstract

It is reported in this paper that the propulsive performance of a ship is surely im一proved by the aid of a wheel of stators installed behind the propeller. This new apparatus converts the rotational motion of the water induced in the rear of the screw propeller into the accelerative motion effectively so as to generate the additional thrust. The principle of the action of it is the same of the old "Star-Contra-Propeller", but it is of a new mode refined by the modern technology. The results of the model tests of one example in the experimental tank showed us that the advantage to be gotten by the stators was five percents up of the propeller efficiency in the open condition and seventeen percents up of the propulsive efficiency in the self-propelled tanker model 6 metres long. From these test results we can predict that the power of the actual ship with the length of 216m will be 10-12 percents down provided with the stators.