| 摘要 |
PURPOSE:To improve the efficiency of a hull and the rudder steering performance by allowing each axis line of a plurality of screws on the right and left sides which are arranged with the bow draft lower part therebetween to be opened outward at a proper angle with respect to the axis line of the ship and reducing the resistance by the radial high-speed water flow directed to the back of the ship. CONSTITUTION:A screw block 1 is equipped with a plurality of screws 3 and 3' at right and left, having a bow draft lower part between them, and each axis line 4, 4' of the right and left screws 3 and 3' is opened outward at a proper angle for the axis line 2 of the ship, and a radial high-speed water flow is formed towards the back of the ship. Therefore, the water stream in the opposite direction to the high-speed water stream is generated in the vicinity of the side of the ship, and the speed of the hull for water and the frictional resistance are reduced, and the resistance of the hull is reduced. When the direction of advance of the ship is changed to the right, only the left screw 3 is revolved, and the revolution of the right screw 3' is reduced, and at the same time, a rudder 5 is steered to the right. When the direction of advance is changed to the left, the opposite operation is executed. |
