a ship propeller is combined with the end of the dam plate blades to increase efficiency and process of the propulsion of a ship by means of the combination of

摘要

A tubular duct is provided for ship propellers with blade tips having barrier plates extending transversely therefrom. The tubular ducts are effectively arranged to extend the barrier plates in a manner which, in operation, directs a fluid stream in substantially shock-free contact with such plates.