- #1
CharlesHoward
- 4
- 0
This is a very curious situation.
I have a large water tank on the top of a hill.
It supplies a gravity fed water system that works fine.
There is an under ground pipe with one end A in the bottom of the tank.
The other end E is about 80 feet below A, and has a faucet.
None of the pipe is above A.
If you open E, then water flows out with good pressure as you expect.
If E is open and the tank empties, air gets into the pipe at A,
and eventually the water stops coming out of E.
All seems normal.
Except ...
If the tank at A is now filled, no water comes out of the open faucet E.
What is the simplest shape of pipe that will cause this?
I am sure the answer involves vapor lock and the fact you cannot siphon water over a 32 foot rise, but that's it.
I have a large water tank on the top of a hill.
It supplies a gravity fed water system that works fine.
There is an under ground pipe with one end A in the bottom of the tank.
The other end E is about 80 feet below A, and has a faucet.
None of the pipe is above A.
If you open E, then water flows out with good pressure as you expect.
If E is open and the tank empties, air gets into the pipe at A,
and eventually the water stops coming out of E.
All seems normal.
Except ...
If the tank at A is now filled, no water comes out of the open faucet E.
What is the simplest shape of pipe that will cause this?
I am sure the answer involves vapor lock and the fact you cannot siphon water over a 32 foot rise, but that's it.