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guds777
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Little Help to Remember - Propeller that Thrusts Water Out of Blades

07/14/2013 8:29 AM

Hi folks i think i remember seeing somewhere on the internet a water propeller who thrust water out of the propellers blade.

I have been googling and googling but no luck.

At least i think i did see this once but i can't find it. Any help is appreciated, thanks...

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Pathfinder Tags: propeller thrust water jet.
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Hendrik
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#1

Re: Litle help to remember.

07/14/2013 9:11 AM

Is this what you had in mind?

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SolarEagle
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#2

Re: Little help to remember.

07/14/2013 9:19 AM

You could be talking about a jet drive which has an impeller enclosed in the drive system....the water enters in a hole in the bottom of the boat....

.....and exits out the back creating thrust....

http://en.wikipedia.org/wiki/Jetboat

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guds777
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#4
In reply to #2

Re: Little help to remember.

07/14/2013 9:41 AM

Thanks for the comment, no there was a set of holes in the edge of the propellers blade, and a water was jet out of the blade, it did have something to do with less drag, more thrust, or it did make a cavity around the propeller, i know the propeller need to dig into the water, but it was something like that.

I just hate it when i remember something but i can't find it again...

Maybe i am confusing two things together, did they not use air thrusters on tip of an airplane propellers, or a helicopter, or a rocket engine on the tip of the blade.

maybe this is it, but i am sure it was something regarding a water propeller and air..

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guds777
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#5
In reply to #4

Re: Little help to remember.

07/14/2013 9:53 AM

it is possible it is air the propeller thrust out, not water.

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Janissaries
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#26
In reply to #4

Re: Little help to remember.

07/15/2013 10:38 AM

That's called cavitation and it doesn't need any external air being injected into the water to create it. It is also not a desired result when it comes to wanting speed but when you increase speed of the propeller it can't be avoided, it is a natural occurrence when a propeller spins faster than the water can close back up when the propeller cuts through it. Which means to gain higher speeds in the water the prop has to spin at a higher RPM ratio wise compared to what it needs to spin at lower speeds for each knot in speed gain.

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cuba_pete
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#27
In reply to #26

Re: Little help to remember.

07/15/2013 12:03 PM

Not used for speed
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Janissaries
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#28
In reply to #27

Re: Little help to remember.

07/15/2013 12:45 PM

Thank you. Good link. I appreciate that.

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kramarat
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#3

Re: Litle help to remember.

07/14/2013 9:28 AM

http://www.simerics.com/gallery_waterjet

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lyn
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#6

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 10:45 AM

Air, not water, although it could work with water, but why would you?

Tip jet - Wikipedia, the free encyclopedia

Never mind. I see you already found that.
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guds777
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#7
In reply to #6

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 11:06 AM

thanks though...

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guds777
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#8

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 11:16 AM

I am starting to think i did just dream this, like so many other things.

If it is something new then it is trademarked, my invention, hahamuhahaha i am gonna be rich...................................................................................joke...

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#9

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 2:39 PM

Check out Hamilton waterjets

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guds777
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#10
In reply to #9

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 4:32 PM

close but no cigar...

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kramarat
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#11

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 4:56 PM

Closest I could find.

http://www.airpostdrivers.com/store/index.php?main_page=product_info&cPath=53_55&products_id=29782

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lyn
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#12
In reply to #11

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 5:20 PM

No.

This is driven by an air compressor and blows air.

guds777

Is there a reason you need this, water propeller. What are you trying to do?

Jet boats don't have propellers anyway, SE. They have impellers.

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guds777
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#14
In reply to #12

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 6:07 PM

I don't need it per se, i was just googling around and came across boat propellers,and it is just stuck in my mind this image of this thing. I just hate it when i can't find what i am looking for...

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guds777
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#15
In reply to #12

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 6:09 PM

i don't get it, was it a link accident or an insult.. hehehehehe...

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#16
In reply to #12

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 7:04 PM

Oh yeah? ....then what do you call these?

Ha!.....

http://www.torquejet.com/

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guds777
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#17
In reply to #16

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 8:07 PM

this is cool.

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#18
In reply to #16

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 8:12 PM

Miniature Kort nozzles?

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#25
In reply to #12

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/15/2013 7:04 AM

The concept is the same.

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#13

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 5:34 PM

Found this for an airplane.....

http://www.dtic.mil/dtic/tr/fulltext/u2/a801340.pdf

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#19

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 8:14 PM

There might have been various devices such as that, but if tried they probably passed out of usage because of inefficiency.

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guds777
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#20
In reply to #19

Re: Little Help to Remember - Propeller that Thrust Water Out of Blades

07/14/2013 9:06 PM

yes i was thinking something similar. Thanks guys...

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#21

Re: Little Help to Remember - Propeller that Thrusts Water Out of Blades

07/14/2013 9:53 PM

Give a prop sales and repair shop in your area a call. Make sure they are a big one and not just a stock facility for outboard props. They may not have what you want but would probably be your best shot or can lead you in the right direction. Contact one who repairs/reconditions those for up to 80' inboards. They have to know their stuff to stay in business.

Good Luck, Old Salt

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stringman
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#22

Re: Little Help to Remember - Propeller that Thrusts Water Out of Blades

07/14/2013 10:31 PM

So could it have been exhaust thru holes in the prop rather than water?

https://www.google.com/search?q=boat+propeller+exhaust+holes&client=firefox-a&hs=wMF&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=i17jUdP7FemCygGt14HgDw&ved=0CEwQsAQ&biw=1551&bih=764
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#23
In reply to #22

Re: Little Help to Remember - Propeller that Thrusts Water Out of Blades

07/14/2013 10:53 PM

That could be it, they do this on performance boats, vent holes...

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KeepItSimpleStupid
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#24

Re: Little Help to Remember - Propeller that Thrusts Water Out of Blades

07/15/2013 12:22 AM

http://www.boatdesign.net/forums/attachments/props/74445d1347995566-strange-propeller-capture.jpg
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cuba_pete (1); guds777 (9); Hendrik (1); Janissaries (2); KeepItSimpleStupid (1); kramarat (3); lyn (2); old salt (1); phoenix911 (1); SolarEagle (4); stringman (1); Tornado (2)

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