Post by Cwi555 on Jun 30, 2012 0:14:09 GMT -7
I worry that would create back pressure on my well and effect my pump. It may be I would need to have an elevated holding tank and run the water down to the wheel by gravity.
I am hoping people who know more about this will jump in and tell me if it will work or not.
Reduction in pipe diameter will not increase the pressure.
hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
hyperphysics.phy-astr.gsu.edu/hbase/pber.html#beq
The Bernoulli principle applies here.
As the diameter is decreased, the velocity of the fluid is increased, but it's pressure is actually decreased.
Effectively reducing that pipe diameter is creating a venturi. As with all of them, the limiting factor is choked flow. What that means is the maximum speed the fluid can obtain will always be less than the local speed of sound.
This is demonstrated via a manometer;
fluid dynamics will allow it to happen, but to satisfy the continuity principle, it must increase in speed. That increase in speed must be on combination of a decrease in pressure to satisfy the principle of conservation of mechanical energy.
Your not really getting any more energy out of the flow restriction, what your getting is more efficient conversion of mechanical energy to electrical energy. The faster you can spin the impeller/pelton wheel etc, the more energy you will create on the generator side.
For low head pressure I would suggest a reverse Archimedes wheel.
