Homebrewed Electricity > Hydro

Combining 2 different pressure penstock lines

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skid:
The best way would be to dump the flow from the higher spring into the waters of the downhill stream. An energy dissipater may be required depending on the elevation change. I've done this professionally on a 30MW Pelton.

Mountain Clan:

--- Quote from: skid on January 27, 2019, 05:36:24 PM ---The best way would be to dump the flow from the higher spring into the waters of the downhill stream. An energy dissipater may be required depending on the elevation change. I've done this professionally on a 30MW Pelton.

--- End quote ---

When it comes to simplicity, I agree. Dumping the higher spring into the lower one is the easiest and least costly method.

I need to come up with a creative and fun way to use up the energy in the water coming from the upper spring, so I dont feel bad about losing the extra psi.

...Hot tub frother, ....Neptune and Nymphs water sculpture, ...mini vertical waterwheel

SparWeb:
 8)

casrwm:
Hi, I don't know if you are still interested...it's a while since the last post.

Basically if you don't want two separate systems you have two options:
(a) if it is feasible to run water from the top spring to the lower one, do that.  Have a small turbine at that point to extract energy from the difference in head between the two springs.  The water coming out of that turbine would then mix with the lower spring water and continue down to your main turbine at the bottom.   If the pipe lengths are reasonable this could be your most efficient option.

(b) Alternatively, mix the flows using something like an ejector pump (as mentioned in a previous post).  At the mixing point, the flows will have the same static pressure but different total (stagnation) pressures (look at Bernoulli's equation) and therefore different velocities.  There will be some energy loss when the two flows moving at different speeds mix together.   You have some control over this static pressure because you can pick the pipe diameter at the mixing point.

Mountain Clan:
Thanks for that information.
Right now, I am combining the 2 flows at the source of the lower spring and losing the energy from about 45' head from the upper spring. It is the method that I know I can count on the results of, for the effort I put into it.

In the upcoming Winter, when our heavy rains return, I will experiment with a directional flow mixing unit further down from the lower spring source and see how that goes. This seems a somewhat simple process and I am hoping not to stress about it, and overthink the dynamics and engineering.

Again, thanks for the response.

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