# Communicating vessels that wont communicate

יש לי אדנית א. מלאה במים המתפתפים ממזגן. רציתי לשתף המים אם עדנית ב באותה גובה ומרחק של כ1.5 מ דרך צינור כותר פנימי 8 ממ. לפי פלס הצינור אופקי. כשהגביתי אדנית א ראיתי קצת זרימה, בלי זה גורנישט , מה עושים לעזור לכלים שלובים להתממש

I have a watertight planter A that catches aircon condensate. I wanted to share this precious water with a neighboring planter B at a distance of ± 1.5m through a pipe of inner diameter 8mm. According to a level the pipe is horizontal. When I raise planter A I see a bit of flow, otherwise gurnisht. What should I do to allow the ‘law of communicating vessels’ to obtain?

Maybe to use a piece of cloth inside the tube?

Best regards

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!! “DIRTPONICS” !!

https://wiki.telavivmakers.org/index.php/Windowfarming

Might be an issue with the placement of the pipe: It seems like it’s too high, and thus the flow must compete with the forces (capillary, surface tension…) active in the unsaturated area of the soil. Lowering the pipe will place you in the saturated area of the soil, and might solve the problem.

The pipe is about 4cm below the surface of the water , so it seems that 4cm pressure head is insufficient to cause significant flow (I do see a consistent puddle at the output planter but the level of the input planter isn’t changing noticeably over several days) . The pressure head is
$$\rho g h ~ 400Pa$$
, while the pressure drop in the pipe is
$$\lambda L/D \rho / 2 v^2 ~ 0.9Pa$$
assuming flow of 10cm/s.
If I’ve done the math right I actually have enough pressure for 2m/s flow so I suppose something must be gunking up the pipe, which is soon to be replaced.

About the failed math rendering above,
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