KISS Principle Marine Propulsion

[anorlunda]

I"m a big fan of the KISS principle in engineering. I'm also a boater. I just found something I wanted to share.



It is a permanent magnet motor in which the propeller itself is the rotor. The video hints that it works with simple reversals of polarity similar to a stepper motor.

That eliminates nearly all of those troublesome intermediate devices and hull penetrations for mechanical power transmission, It is about as KISS as I can imagine for an electric drive.

Put one of those forward and another one aft, and you have a superbly maneuverable vessel.

How to generate the electric power on board is a separate question.

 

[RonL]

I"m a big fan of the KISS principle in engineering. I'm also a boater. I just found something I wanted to share.How to generate the electric power on board is a separate question.

This is almost the exact concept in my mind when I made the comment in the Boeing Challenge thread, my thoughts are a very lite-weight flying platform (more complicated) where this is a perfect heat exchange opportunity. One has only to imagine a closed loop steam cycle within the blades and hub section. electric is generated at the outer ring and a resistance inside the blade tips makes high pressure steam that moves to the hub and provides torque to drive the blades, the bulk of the blade area serves to exchange heat that returns the spent steam to liquid and the cycle repeats.

ps. The mechanics would be similar to the workings of a bubble jet printer, just a much greater scale. Perhaps this might help build a mental picture of the basic workings.

 

[CWatters]

The pump in our washing machine works in a similar manner. There are permanent magnets on the rotor which is submerged in the water. Means there is no need for a water tight bearing which reduces chances of a leak.

 

[Baluncore]

... with reduced noise and vibration levels and hardly no cavitation.

Is that a double negative there?
What has cavitation got to do with it? Maybe the blades are so poorly shaped that they have problems with cavitation.

 

[anorlunda]

Is that a double negative there?
What has cavitation got to do with it? Maybe the blades are so poorly shaped that they have problems with cavitation.

I think if you add more vanes on the prop, you can reduce the RPM for the same power. At reduced RPM you have less cavitation.