The invention relates to a
stern structure for an
internal rotation double-
paddle ship. The
stern structure comprises a pair of small
tail fins. In a vertical view, each small
tail fin is arranged at a horizontal inclination angle from front to back towards the central axis of a
hull, and a pair of supporting shafts in the small
tail fins incline at the same angle. The small tail fins inclining inwards conform to the direction of a flow field of a
stern, tail
water flow separation is reduced, and therefore resistance is reduced. In addition, pre-
rotational flow with the rotating direction opposite to that of paddles act on the paddles, so that the rear tail flow rotation of the paddles is weakened or eliminated, and the effects of tail flow
energy loss reduction and propelling efficiency improvement are achieved. By the adoption of the stern structure, the tail flow field is effectively improved, the
propeller exciting force is reduced, the
propeller first-stage exciting force under designed draft is reduced to be below 1.5 kPa, and the ship comfort is improved; the structure is relatively simple, the structure and the size of a tail attaching body are not additionally arranged or changed, and optimization and implementation are better facilitated; and the economical efficiency and rapidness are better considered.