Kaplan?

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The link to a picture of a Kaplan that I saw in another thread today looks a whole lot like an old Jet Ski pump (I have several laying around).  I'll try to take a picture of one later today.  The ones I have are about 5" in diameter and designed for axial flow.  They have an aluminum housing with 15~17 degree impeller and drive shaft.  Having the pump, housing and drive shaft already there it would be pretty easy to hook up an alternator, and keep it completely dry.  For that matter the entire WET portion could be completely sealed so that it would hold pressure/vacuum.

I don't know the first thing about water power so I don't have any insight into the practical mechanics of what really works.

Is this a totally hair brained idea, or might it have some merit?  

Put it in the right section for you. TW

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Sorry, I put this in "Water" instead of "Hydro".  My mistake.

[spinningmagnets]

Banki is a proven generator with low-head conditions, certainly the first option for consideration. Also very low up-front cost.

If you are willing to build a small pond and flume, with a 7'-10' vertical drop tube, a Kaplan may be viable. An interesting feature of this story is that the turbine is near the top of the tube, and runs half off the suction below the prop instead of all from the pressure/flow from above.

http://www.fieldlines.com/story/2008/6/22/191210/965

As far as jet-ski prop, sounds like a fun experiment. Best of luck.

(PS, I have not owned a hydro-gen yet, this info is only from research file)

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That story is what got me thinking about this.

Unfortunately I have no water source to test it on.

Maybe, when I make my planned rain water collection system, I'll be able to try it out during the next hurricane.  

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Here are some pictures of one of the Jet Ski pumps I have.  This one is actually a combination axial/redial flow pump off of a JS-550.  It has internal bearings top support the impeller and a splined drive shaft slips into it.  It also has "straightening vanes" (seen in the 2nd picture) behind the impeller which are designed to reduce the spin imparted to the water to prevent torque from causing the Jet Ski to lean to one side under acceleration.

Side view (Water Intake is on right, Jet Nozzle on left)



rear view



front view

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I always notice my typos right AFTER I post...

It is a combination Axial/Radial (not redial) pump

[domwild]

Hi,

The Austrian engineer Kaplan developed the turbine for low head/high volume situations and they are used along the Danube and other rivers which are dammed up. I doubt you would have the volume to drive a "useful" alternator as the rotor looks very small in diameter.

Google "Kaplan+power" for the power formulae and try to work out how much volume you need given the dia. of the impeller.

[A6D9]

I think it could work..only one way to really find out....TRY IT.  

any ideas what these go for in cost?   I'd try it this spring.  i got a nice source of water in my back yard and a banki scares me for soem reason.

even if it was only 25-50 wattes  it be better then nothing...i could have a back up system for when we lose power to keep some stuff working.  

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I suspect that it would take a LOT of pressure to make it work...but once you got it turning it would produce a LOT of power.  It is designed to go behind a 45 HP motor at about 6000 RPM (not that I would expect it turn anywhere near that speed).  It was also developed originally from a water pump, so I think it might work well in reverse.

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Oh yea, you can get them for about $50.00 on E-Bay from time to time.