STERN DUCT

To provide a stern duct with easy adjustment of propulsion by being capable of increasing the propulsion without greatly changing number and configuration of ducts from a conventional structure.SOLUTION: A stern duct 1 comprises a duct body 11 which is provided around a stern tube 9 in stern before a propeller 5 of a vessel 100, is a single cylinder with axial direction facing vessel length direction, and is arranged in a position and posture with lower pressure in surface vicinity of the cylinder than outside, and has a slot 23 in the duct body 11 which is a long hole formed along peripheral direction of the tube of the duct body 11 for communicating inner periphery and outer periphery of the duct body 11 conducting a part of water flow flowing outside the duct body 11 to inside the duct body 11.SELECTED DRAWING: Figure 3 【課題】ダクトの数や外形を従来の構造から大きく変えずに推力を増やすことができ、推力の調節が容易な船尾ダクトの提供。【解決手段】船舶１００のプロペラ５の前方で船尾のスタンチューブ９回りに設けられ、軸方向が船長方向を向く単管で、管の表面近傍において内側の圧力が外側よりも低くなるような位置と姿勢で配置されたダクト本体１１を備える船尾ダクト１であって、ダクト本体１１の管の周方向に沿って形成されてダクト本体１１の内周と外周を連通する長孔であって、ダクト本体１１の外側を流れる水流の一部をダクト本体１１の内側に導入するスロット２３をダクト本体１１に備えることを特徴とする船尾ダクト１。【選択図】図３