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water turbine

water turbine

water turbine

(OP)
Hi,
I have a question regarding a hydraulic pressure with embedded water turbine mechanism.
The hydraulic cylinder contains two cylinder barrels of different diameters. For example the top cylinder barrel has a diameter of 20cm and 2cm for the bottom one. They are inner liquid connected. If the top piston is pushed inward for 1mm, the bottom piston will be pushed outward by 3cm approximately.
I am wondering if a reaction water turbine is installed in the bottom cylinder barrel, will the moving fluid get the turbine runner rotating under the condition that the top piston is pushed in and pulled out for a once?
And where can I find a water turbine with such small size?
I do really appreciate if someone can help me and give me an explanation!
Wazi
 

RE: water turbine

Your turbine will not rotate.  There will be no flow through the blades.  There will be flow into the smaller cylinder, but not across the turbine.  Or, does the smaller piston move without moving the turbine?  That is, are the turbine and shaft stationary relative to the smaller piston?

The distance the smaller piston moves will be the square of the area ratio times the larger piston distance.  L2 = L1 * Area1^2/Area2^2.  In your example L1 = 1 cm, L2 = 100 cm, not 3 cm.

Ted

RE: water turbine

In other words, see www.mrwizard.com

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water turbine

(OP)
Hi Ted,
Thank you very much for the help!
Actually L1=1mm, and L2 = 10cm if diameters of the top and the bottom cylinder barrels are 20cm and 2cm respectively.
The small piston will move no matter whether the turbine rotating or not. The turbine has an extensive connected shaft out of the cylinder barrel, and in fact, this is going to drive a flywheel. That is, the position of the turbine and the shaft is fixed, and when the top piston is pressed down, there will be a fluid flow through the blades.
I am not sure whether I make myself clear here.
So if this is true, will the turbine rotate?
If I know the total input energy put in to the top piston, how can I know the rotary energy stored in the turbine hence the speed of the turbine?
 

RE: water turbine

wazi

I'm not sure that the turbine will rotate, much less drive anything.  However, it sounds like you've convinced yourself that it will work and what you're really wanting is a recommended place to buy a turbine of the correct size. I'd suggest Google as a place to start looking for turbine manufacturers.

You might consider making a prototype, even if it's a slightly different size than desired, with a clear outer container. That way you can test your hypothesis.

Patricia Lougheed

-----
"Somebody on this Internet forum said it was ok" is not a sufficient explanation when responding to a lawsuit.

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RE: water turbine

wazi, sorry I misread L1 as cm and not mm as you posted.

Actually L2 will be greater than 10cm since the piston2 area is less than that of a 2cm circle.  You must subtract the area of the shaft tube that passes through piston2 from the area of the 2cm circle to know the effective piston2 area.

Ted

RE: water turbine

Unless I am missing something, or the drawing isn't clear ...

The turbine will not rotate.  Ask yourself - will it turn clockwise, or counterclockwise?  Because the same force will be on the "right hand" side as the "left hand" side, and, consequently, the turbine will not rotate (?)

RE: water turbine

(OP)
Hi AllHandlesTaken,

Actually, I think you can by one of those reaction water turbines, they work when they are totally immersed under the water, when the water flow through it, the blades are directed in such a way that different pressures producing on it, thus make the turbine rotates.

wazi

RE: water turbine

(OP)
Hi vpl,

I haven't convinced myself that it works, actually I have no idea if this works or not.

I've searched for a lot of suppliers of water turbines, but still can not find a suitable one, or even a one to make a prototype and verify the hypothesis result...

So can anyone help me with this?

RE: water turbine

(OP)
hi hydtools,

Thank you for noticing me of the effective piston2 area.

wazi

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