Toroidal propellers: A noise-killing game changer in air and water

[BARRY STOTT]

Here’s an article on a new design for propellors on boats and drones that is much quieter and at least 20% more fuel efficient:

https://newatlas.com/aircraft/toroidal-quiet-propellers/

With only one manufacturer so far, it’s not cheap, and the fuel savings would offset purchase price much faster on a thirsty powerboat, but it does extend powered cruising range by a significant amount and greatly reduce the noise level which might make it worth the price.

Please report back to us if any Nonsuch owner splurges and gives it a try!

Barry Stott
Chadds Ford, PA
ebs...@aol.com

[bobby.il...@gmail.com]

This type of propeller would make a lot of sense when paired up with an electric motor, not so much for the noise reduction but certainly for fuel efficiency

Bob Illingworth
Nonsuch Luck 30U #367 (GBR1262T)
Moored Titchmarsh marina, Essex, UK; cruising the rivers of East Anglia, and, the North Sea.

--
You received this message because you are subscribed to the Google Groups "INA Nonsuch Discussion Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to INA-Nonsuch-Discussi...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/3D33A1E5-9BDE-40A6-A1A3-25007723FBCC%40aol.com.

[Mike BIANKA]

Not sure if it would make much difference on boats using electric propulsion like my 30U. Since EP is already pretty quiet compared to using diesel propulsion. But, if it improves thrust in the same size prop then that would be a game changer and might be worth a prop changeover..

Mike

BIANKA

1986 30U

Long Island

[Mark Powers La Reina 26C Vancouver, B.C.]

It looks interesting.

 I note that most of the props on our boats are spinning at between 1000 and 2000 rpm. At this speeds the chart showing efficiency gains indicates that the improvements at those prop speeds are in the 3% to 5% range. A nice improvement but cost recovery might take a while. I also wonder what the drag will be when the boat is sailing and the prop stationary. Here is a link to a youtube clip where a fellow has used a toroidal prop for a computer cooling fan. A standard computer fan was quieter. The presenter wondered if the difference from the MIT results were party due to the lower speed the computer fans ran at. 

https://www.youtube.com/watch?v=4ImeOKgD_Dw

I look forward to hearing from an owner that takes the plunge when one is available to our boats.

Mark Powers

[Bob Neches (Me Gusta, Nonsuch 26U #233)]

Does look like an interesting technology.   Max rpm is 1750 rpm for an Electric Yacht QT10 motor, representative of most electric boat systems for our size.  Not even the 2000 rpm range that Mark mentions.  So the efficiency gains aren't going to justify switching yet for many electric Nonsuch owners. 

Fun to watch, though.  In addition to the question about drag, I'd also be curious what they do when freewheeling; do they facilitate or interfere with regeneration?

-- Bob

   Me Gusta

   Nonsuch 26U #233

[Mike]

Bob

Good point the ability to regen under sail would be a factor as to if this new prop technology is worth the upgrade to those of us who use electric propulsion as auxiliary power.

Mike

BIANKA

1986 30U

Long Island

biankablog.blogspot.com 

https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/f6bdf3d9-8867-49d1-a82d-3de5d3a1ddafn%40googlegroups.com

.

[bobby.il...@gmail.com]

Mike,

As electric motors are capable of much higher rpm than diesel engines, I wonder if a much smaller toroidal propeller operating at very high rpm would offer an electric yacht much better efficiencies.  The downside might be a much-reduced regen when sailing.

To view this discussion on the web visit https://groups.google.com/d/msgid/INA-Nonsuch-Discussion-Group/3c82bc68-50f0-4390-84bd-165a0be2d93dn%40googlegroups.com.