摘要 |
A duct 4 is provided on the suction side of a ship's propeller with blade tips having barrier plates 3 extending transversely therefrom, the duct being arranged to direct a fluid stream in substantially shock-free contact with the plates. When the propeller is rotating, the plates 3 describe a body of revolution which substantially constitutes an extension of the after side of duct 4. <IMAGE> |