Kort Nozzle Design

Kort nozzles sometime referred to as ducted propellers are on the design list.

Denso fuel nozzle. The shrouds flow accelerating effect and hydrodynamic inner profile greatly improve the thrust efficiency of the propeller at lesser speeds. The kort nozzle is a shrouded propeller assembly for marine propulsion. Designs have been made for controllable pitch propeller blades for kort nozzle operation up to 5300mm diameter.

During all these years it has been demonstrated that an increase in propulsive efficiency can be achieves in work boats by surrounding the propeller with a foil shaped shroud. The kort nozzle is a low speed ducted propeller design used on ships and boats consisting of a conventional propeller housed within a specially designed shroud. Kort engineers therefore have the expertise to provide powering and performance estimates for every application from 100mm diameter propellers for an rov thruster to 4000mm and above for commercial vessels.

These are essentially propeller shrouds with an airplane wing cross section which increase low speed thruster performance. A kort nozzle is referred to as an accelerating nozzle and is generally a marin 19 a profile or a marin 37 profile. The cross section of the shroud has the form of a foil and the shroud can offer hydrodynamic advantages over bare propellers under certain conditions.

Advantages are increased efficiency at lower speeds 10 knots better course stability and less vulnerability to debris. The kort nozzle is a shrouded ducted propeller assembly for marine propulsion.