| 摘要 |
PROBLEM TO BE SOLVED: To provide a ship rudder that attains improvement in propulsion efficiency.SOLUTION: The ship rudder includes: a rudder blade 30 disposed on the same axial center at a rear side of a propulsion propeller; and a top end plate 40 and a bottom end plate 50 which are provided in a top end portion and a bottom end portion of the rudder blade 30 while being expanded to both port and starboard sides. The rudder blade 30 includes a plurality of ribs 70 disposed on a rudder surface at both the port and starboard sides in parallel with the top end plate 40 and the bottom end plate 50. The rudder blade is formed from a front edge part 31, an intermediate part 32 and a rear edge part 33 in a contour of a horizontal cross section. The front edge part is formed by protruding forwards in a semicircular shape. The intermediate part continued to the front edge part is formed by increasing a width in a streamline shape towards a widest portion and gradually decreasing the width towards a narrowest portion. The rear edge part continued to the narrowest portion of the intermediate part is formed in a fish tail shape by gradually increasing a width towards a rear edge widest portion of a predetermined width. The plurality of ribs are disposed in the narrowest portion of the intermediate part. |
