FYI http://nopr.niscair.res.in/bitstream/123456789/6211/1/IJMS%2038(3)%20338-345.pdf is a link to a paper on design of a thruster using a Kort nozzle. The thruster is small relative to what we normally us at 0.5 hp but the paper is interesting in that it goes through the design process using both bench testing and CFD. It gives some good references on software for thruster design and standard profiles for thrusters props. My interest in this on the boat I am doing the conceptual engineering on, I would like to use a Kort nozzle both from an efficiently point of view and the safety of a shrouded prop. I am thinking it would be straight forward to use the process outlined in the paper to marry a Minn Kotta 101 motor with Wagenigen ducted propeller KA series 19A. This would give a good low cost ducted thruster a psubber could fabricate.
Cliff