New Hydro Project

[dbcollen]

As a small scale manufacturer of micro-hydro turbines, I have decided to try and develop a fairly efficient, easy to manufacture impulse runner to replace the very costly Harris Hydro pelton runners I have been buying, here is a prototype.



I know that it needs to have more cups, but I had several feet of this 12 sided stock that I had already machined for rotor cores, so 12 cups it was.





Here is the cups from the angle of the water jets. There is a very sharp leading edge on the cups, there should be good laminar flow across the surface of the cups, and about 170 degree redirection of the water. I may put a ring around the outside of the cup, I will decide after initial testing.

Here is the nameplate on the 3hp total stainless washdown rated induction motor that will be the alternator. I cap excite these, they are not conversions. This one should produce 1.5 to 2 KW at 500Vac at around 2100 rpm. My current penstock is capable of around 1500 watts.





I will keep everyone posted with the results of testing. I am a week or so from getting this one finished.

Dustin

Mad River Wind and Hydro

[dbcollen]

pay no attention to the really ugly welds, I was running a big mig welder that I had never used before off a generator that really couldn't keep up. the welds looked better at the finish, as I got used to the welder.

Dustin

[dbcollen]

Since it wasn't clearly described, the circle represents where the jet of water will strike the cups.

Dustin

[thirteen]

because of the straight edge of the blades would a nozzle shaped in the form of a   D let you direct more water to the straighter edge of the blade. How many nozzles are  to have on this wheel? Just and idea.

[MattM]

Isn't one of the keys of the pelton runner the fact that the flow is directed towards the center of the wheel, boosting its tangential velocity by restricting its relationship to the wheel diameter-wise?  Take a weight on a string and twirl it around your head.  As it twirls shorten the string and watch the weight suddenly appear to accelerate.  The weight still has the same tangential velocity, but because the diameter of the circle has shrunk the rpm's increase.  You theoretically lose torque for the benefit of rpm's.

Your turbine appears to work inside-out, which by the physics should slow the turbine.  You theoretically have more torque at the sacrifice of velocity. Just a thought, not a criticism.

[Flux]

This is a Turgo based blade and I see no reason why it shouldn't work perfectly well. Normal Turgo blades are curved in two directions but as long as the emerging flow clears I think it will be ok. For it to work well you will need the blade dimensions to be bigger in proportion to the jet size than a proper two dimensional casting but for normal use I would say it will be fine.

I think the Turgo runner is a lot more forgiving than the Pelton.

Flux

[dbcollen]

Yes Flux, I have used several different turgo runners and was attempting to come up with an easy to mass manufacture design so I will not have to purchase them from others. The Harris pelton runners have gone down in quality, and up in price, and ES&D wants $700 for thier turgo runner. I think it should have more cups, so I will test this one and will also make one with 24 cups, and see which one performs better. It took me three hours of shop time to make this one, if I did a production run of a few hundred it would take way less time each. At $80/hr I am only $240 of my time into this one.

Dustin

[dbcollen]

I'll have to try to find some "D" shaped drill bits and try that.

It would be difficult to machine a D shapes orifice and matching pintle, and I don't think it would make any real difference.

Dustin

[hvirtane]

It seems to be a really nice machine when ready.

What is the current estimate of the price for a ready made thing with the generator and everything?

- Hannu