Propeller break through?

[kach22i]

FYI:

From another forum...................Water and Air versions.

http://hovercraft.org.uk/FUDforum2/index.p...ca0906a36277bf8

I dont know if this will be of interest to anyone, but a year or so ago I visited a company in Berlin called Evologics who make all manner of bio-inspired equipment. They have come up with a new propeller design based on continual planar surfaces that runs with a greater efficiency and with much less noise (this is why we were interested, for underwater propulsion) than a standard propeller. No leading edges on the prop. mean no tip-vortices, so less energy is lost in combating turbulence.

There is not much information about it, but there website is:

http://www.evologics.de/propeller_index.php?sectionID=5

There is a video of the props working on the home page of this website, but is probably in german:

http://www.lexi-tv.de/lexikon/thema.asp?InhaltID=2733

Kinda neat idea, thought someone might find it interesting

Dylan

It must be a bugger to balance, looks interesting.

In the video they show the wing tip of a bird, then why is the end of the fan blade not with multiple tips?



http://www.evologics.de/propeller_index.php?sectionID=5

Even the propeller can still be improved!

With their fanned wing tips, birds already use it longer than the age of mankind, and avionics made the retrofit in the last years. The topic is the principle to split up vortices at the wing tip, known as "winglets" in airplanes.

The consequent further development in aero- and hydrodynamic terms led to a stunningly simple, but even more stunningly efficient propeller.

Whether in aircraft propulsion, marine technology, wind energy or ventilators - this technically new design loses signifcantly less energy to tip vortices, provides an increased efficiency ratio, operates as silent as technically possible and comes with a self-stabilizing shape.

[MichiganMat]

Wow, the video is pretty cool.

[Seahawk]

Very interesting...but stoopid!

Just kidding. Interesting stuff.

Efficient props are the Holy Grail. I kept waiting for the German pronuciation of, "wing tip vortices".

From fertile minds.

[kach22i]

I've oftened wonded why there is no ring or hoop connecting the blade tips of conventional fan and propellers. It seem to me that it would add strength. Perhaps the extra mass and the moment of energy would just be to great and offset any possible advantages.

My ideawould mostly be applied to ducted propellers and fans, to help narrow up the clearances and improve efficiency - by reducing blade tip vortices.

It seems this new propeller does that and more.

[Seahawk]

Originally posted by kach22i
I've oftened wonded why there is no ring or hoop connecting the blade tips of conventional fan and propellers. It seem to me that it would add strength. Perhaps the extra mass and the moment of energy would just be to great and offset any possible advantages.

My ideawould mostly be applied to ducted propellers and fans, to help narrow up the clearances and improve efficiency - by reducing blade tip vortices.

It seems this new propeller does that and more.

In helicopters, they have addressed, as you correctly named (I did not), "blade tip vortices" with ducted tail rotors...sometimes called a finistron.

The interesting aspect to me is that finistrons are in line with the direction of the vehicle. The propeller in the link
is not. For every ring or hoop (shroud), there is an added drag coefficient that might impact the props benefits.

I wish I understood German!

Thanks again for the post.

[fastpat]

Originally posted by Seahawk
In helicopters, they have addressed, as you correctly named (I did not), "blade tip vortices" with ducted tail rotors...sometimes called a finistron.

The interesting aspect to me is that finistrons are in line with the direction of the vehicle. The propeller in the link
is not. For every ring or hoop (shroud), there is an added drag coefficient that might impact the props benefits.

I wish I understood German!

Thanks again for the post.

I think the only application for the "Fenestron", from Latin from fenestra, window, is in the French Aerospatiale/Eurocopter
365 Dauphine used by the Coast Guard.
http://www.shastalake.com/images/boatingsafety/coastguard-009.jpg

[Seahawk]

Originally posted by fastpat
I think the only application for the "Fenestron", from Latin from fenestra, window, is in the French Aerospatiale/Eurocopter
365 Dauphine used by the Coast Guard.
http://www.shastalake.com/images/boatingsafety/coastguard-009.jpg

Ok, wrong again (dammit)...the fensetron is also in the Gazelle, and the Comanche, before it was cancelled.

I had the pleasure of working the Comanche program...but based on my spelling prowess, maybe I didn't.

[fastpat]

Originally posted by Seahawk
Ok, wrong again (dammit)...the fensetron is also in the Gazelle, and the Comanche, before it was cancelled.

I had the pleasure of working the Comanche program...but based on my spelling prowess, maybe I didn't.

It's French, we're not holding you accountable for that.

To me, the most fascinating devopment in helicopter designs is the NOTAR, put into production by only one manufacturer so far, Hughes/Mac-Doug MD520N no tail rotor machine.
http://www.airliners.net/open.file?id=0190996

[Seahawk]

Originally posted by fastpat
It's French, we're not holding you accountable for that.

To me, the most fascinating devopment in helicopter designs is the NOTAR, put into production by only one manufacturer so far, Hughes/Mac-Doug MD520N no tail rotor machine.
http://www.airliners.net/open.file?id=0190996

I've had the pleasure of flying it...

Relatively old technology, however. I first flew it in the late '80's.

[kach22i]

Thanks for the new term.

http://images.google.com/images?svnum=10&hl=en&lr=&safe=off&q=Fenestron&btnG=Search