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Notes and ideas for pedal powered boats from this site and around the web.
Pedal powered azimuth drives and or kort nozzle; contra rotating propellers. Hull to be narrow beam (ratio of 6 to 1 : to 10 to 1 length to beam ratio) Probably displacement type; possibly semi-submersible.
Possibly use two azimuth drives with applied braking on a differential to give independent drive power control.
./Car Differential with Balls-IkpTGkMxgLc.webm
./Car Differential with Belt 1--dtBWDVshYY.webm
./Car Differential with Bevel Gears 1-YjhzkV5Ya2k.webm
./Car differential with locker-xTYGVGU_g88.webm
./Face gear 6 - Drive for coaxial propellers 12-xda1WgL9fd0001.webm
./Drive for coaxial propellers 1-4mWe9EnW9hE001.webm
./Drive for coaxial propellers 9-t5u-_HslCxg001.webm
Below image, we are focused on the nozzle on the left side, for increased thrust.
Comparison of Drag Coefficient Between Kort and Rice Nozzles
OPERATIONAL ANALYSIS OF A RICE SPEED NOZZLE
Figure 3 Transverse View of Rice Nozzle.
Because of this pressure difference, a force P (Figure 4) is created on the external surface of the nozzle that is always perpendicular to this surface.
Due to the design of the outside trailing end part of the nozzle, the horizontal component of this force P creates an additional forward thrust on the nozzle; increasing the total thrust of the vessel.
Figure 4 Pressure Differences Creates Additional Forward Thrust.
Up to 40% of the total thrust is generated by the nozzle itself and is transmitted directly to the hull.
Add length to tip of prop blade where nozzle is wider to reduce clearance distance, shown in blue.
Kaplan Prop, for use in kort nozzles
For straight drive
./Face gear 6 - Drive for coaxial propellers 12-xda1WgL9fd0.webm
./Drive for coaxial propellers 9-t5u-_HslCxg.webm
Rear prop should have more blades than front prop,ie four blades and five blades; however both props should provide equal thrust.
For Azimuth or outboard type
./Drive for coaxial propellers 1-4mWe9EnW9hE.webm
Constant-velocity (CV) joints
./Tripod joint animation in solidworks--RMxVcq-RhQ.mp4
Power transmission, and direction. Spiral gearing shows better efficiency
Drive train: Bicycle pedal, with long chain going under seat (like recumbent tadpole trikes), back up to an sprocket axle, between two azimuth drives (contra-rotating prop?) in kort knozzles.
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