AIRFOIL-SECTIONED DUCT FOR INSTALLING ON STERN OF SHIP

摘要

The present invention provides an airfoil-sectioned duct for installing on the stern of a ship, the circular duct being installed in front of a stern propeller of radius R, wherein the duct has an airfoil section, a radius of 0.7R at the back end, and an angle of attack of 14 degrees. According to the present invention, by rectifying and accelerating the flow of the flow field entering and passing through the interior of the duct, the pressure recovery of the stern is promoted and thereby the resistance performance of the ship is improved, and moreover, the propulsive performance of the propeller can be improved by the changes in the wake entering the propeller. Furthermore, by configuring the cross-section of the duct to have the shape of an airfoil and suitably configuring the angle of attack of the duct with respect to the inflow flow field, not only can the drag of the duct itself, which is an addition, be minimized, but additional thrust provided by the duct itself can be expected. Also, according to the present invention, as the shape of the duct is comparatively simple and installation can be completed simply by attaching the duct to the stern, production and installation of the duct are simple and cost therefor is economical, and the present invention has the benefit of being applicable not only to new hulls but also to existing hulls in operation.