SHIPBOARD PROPELLER Russian patent published in 1999 - IPC

FIELD: shipbuilding; shipboard propellers. SUBSTANCE: shipboard propeller has blades with damping members secured on their surfaces; damping members are made in form of mechanically secured insert located along trailing edge of each blade; layer of viscoelastic material is placed between surfaces of inserts and blade. length of damping member is no less than 0.1 of length of blade profile chord and its width is equal to 0.1 to 0.5 of local thickness of blade section profile at total length of damping members no less than 1/3 of length of blade trailing edge. damping members may be made in form of part of profiled body of blade with its trailing edge and inserts are made in form of packages consisting of two or more components with additional layer of viscoelastic material placed between them. EFFECT: reduced level of vibrations and noise created by propeller, first of all noise generated by blade edges.