Hello oli80 and thank you for your help
The case mentioned above is quite specific because the outlet level is below the level of the water in the well. (which is quite rare when using a well)
As said in one of my previous messages, I saw this system operate in Vietnam and the water source, a pond, was at least three meters below the level of the bottom of the siphon barrel. The barrel was about 1,5m above the surface to water.
A system like a Lemichel siphon is unusable in my case.
I should have said at the outset that my goal is to install a lifting system in Africa. So: anything that is complicated, expensive or dependent on a foreign supply is excluded.
I can easily find a 200l barrel in scrap as in the video, there is everywhere here, I can easily find pvc pipe, even if it is of poor quality, however find what to make a Lemichel system is excluded . (and if I find it I will have it stolen within a week of installation ....)
oli 80 wrote:there were all kinds of machines to raise water, some are still made in poor countries
try to search for "barrel pump" on youtube or google
good night
The video of the first post is a "barrel pump".
I plunged back into the mechanics of fluids which I had practiced a few years ago, the fluid being for me at the time air, but it remains a fluid.
At first glance it seems that the difference in weight between the feed water column and the outlet water column matters. Hence, for example, the difference in diameter between the inlet and outlet pipes of the barrel that can be seen on some videos of barrel pumps. In fact it seems that the length of the garden hoses is generally greater than the length of the supply hose, this is enough to create this difference.
In all cases it is necessary to provide for a re-priming of the system, if only to compensate for the loss of depression in the barrel due to the air dissolved in the water (and the air at ten cents is not dear ..) which will "evaporate". It also seems that the installation on the drums, the two taps on the top of the drum, is made to re-prime the system.
Some problems could be avoided with check valves or by increasing / decreasing the pressure by varying the temperature in the barrel, but that would be crushing a chip with a steamroller. In Africa it would not be reasonable ;-)
Fifi