10W water turbine not rotating 1

[Jon9]

Hello,

I have a small water turbine which I am trying to use to generate electricity from fairly water flow. The issue that I have is that my water flow is too low to start the turbine and therefore generate electric power (even minute one)I was hoping that someone here might know a way to reduce friction or in some other make it easier to rotate the water turbine? The device is shown below, it's simple as water flows in one way and out from the other to rotate a turbine and generate electricity. I've also attached a photo of the disassembled product as I suspect I will have to open it to do something about it. This isn't actually my own photo but I have an identical water turbine. Would oiling the blades actually do anything given that it's magnetically attached as shown at 3:40 in the video or is some other better way?

https://www.youtube.com/watch?v=mtMO3VmCmiQ

(where I got the photos from)

 

[dgallup]

You probably just need more head, the difference in elevation between the water inlet and the turbine outlet. You don't need a lot of flow for something that small.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[1gibson]

What type of motor? If it's already hooked up to a load before it starts rotating, then it will take more force to start moving. Spin it by hand with wires disconnected, then try again after it's connected. If it's marginal, maybe you can let it start spinning then connect it electrically, and it might have enough inertia to keep moving.

Restricting the inlet with some sort of insert so the water has a higher velocity directly onto the blades, is worth looking into.

 

[MintJulep]

Do not intentionally oil any water stream.

 

[chicopee]

That's what happens when you buy Chinese junk.

 

[BrianPetersen]

Can't get something out of nothing, either. If there's next to no pressure and thus next to no flow, there will be next to no motivation to spin the turbine and thus, nothing to make power from. "Reducing friction" won't magically make power appear out of nothing.

 

[TheTick]

Standpipe?

 

[LittleInch]

Are you and adamj2 related??

https://www.eng-tips.com/viewthread.cfm?qid=450914

It's not your flow that's the issue its the differential pressure across it.

also this thing isn't a turbine, it's a water wheel.

I suspect this thing has permanent magnets in it and they take a certain torque to move the shaft and generate any electricity. Oiling anything will have zero impact other than polute your outgoing water, but oiling the "Blades" won't do anything at all.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Jon9]

After reading all these comments I believe I was looking at the problem the wrong way. The issue seems to be that the starting torque to move the shaft is too high for my head, which is currently only few centimeters. I don't see how this starting torque can be reduced so the only option really is to somehow increase the head.

 

[hydtools]

Capture flow farther upstream and deliver it to the generator at your downstream location. That would present higher head to the input.

Ted

 

[itsmoked]

A couple of centimeters.. Forget it.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[LittleInch]

"A few centimetres"???

What are you using? A pint glass?

What's wrong with the tap?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Jon9]

Thanks for the encouragement.

But in all seriousness I was trying to work with a small scale prototype of a water system hoping that it might generate some power. Clearly I've overestimated the output I should get. At least now I know that fault is not the turbine's but rather my own design/calculations.

 

[itsmoked]

A turbine like that is going to have lots of losses and be maybe 20% efficient. It's also going to have minimum flow requirements. Your really low head just will not surmount that. Very little would. You could design from scratch something that might but it would be a long road to hoe and take a lot of iteration.

Keith Cress
kcress -

http://www.flaminsystems.com

 

[MacGyverS2000]

A really long impeller blade and the water dribbling onto the end of it would get the motor moving... but why?

Dan - Owner

http://www.Hi-TecDesigns.com

 

[waross]

That is a positive displacement pump.
It is similar in principle to a vane pump.
There is a rotor off center in a round housing.
The blades are always in contact with the outer housing.
As the rotor turns the volume between the blades gets larger on one side and smaller on the other side.
They have a lot of friction.
In some applications the power to overcome friction is more than the power to pump water.
If you keep increasing the water pressure it will probably eventually turn.
At that point you may look at the pressure needed and abandon the idea.


Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[waross]

I recently bought one of those for an emergency job.
Mine was turned by a battery drill.
The pump failed in a few minutes.
Plan B.
Spend $120 on a proper sump pump.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[IRstuff]

Seems to me the video pretty tells you that you need a flow that's on the order of 3 in/s, which works out to be ~10 mL/s

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[LittleInch]

Waross. You're close but this is just a simple water wheel. It's just some cheap device marketed as being able to charge phones and batteries.

In theory yes but you need an awful lot of high pressure water. There is a gap between the rotor and the casing and if you don't have the flow or head pressure to drove it friction and resistance from the presumably magnetic general is too [pre][/pre]much

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.