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segalion / raspipool

Swimming Pool Automation Systen with Raspberry Pi + Home Assistant
MIT License
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Fluids dynamics #4

Closed metropt closed 3 years ago

metropt commented 4 years ago

How did you design the bypass Tube dimensions? I suppose you need to guarantee some pressure between the main pumping system and the bypass, is that right?

Thank you

segalion commented 4 years ago

I dont understand your question. The bypass is carefully designed to:

  1. get a consistent flow (high enough) It is garanted because it is in recirculating mode, so a little part the main returning flow (from filter) is going to be reabsorbed by the pump, to by-pass, and go again to the filter.
  2. get an adecuate flow (low enough). It is garanted by the 20D pipes instead 50 or 65D main
  3. the water recirculating is always filtered before measurement, to improve the lognevity of the probes
  4. easy maintenance: outiside the main flow, with 20D valves, you can cut the bypass for maintenance (change probes, callibrate, etc.)
  5. allways wet. To mantain the probes inside water, the bypass need to be at the most bottom, over a 50D pipe (more water, more difficult to evaporate).
ghost commented 4 years ago

It would be nice to include those rationale on the wiki. I was about to question the design after reading the https://github.com/segalion/raspipool/wiki/Bypass-for-sensors but it is pretty clear with your explanation. Thanks again for your work ! Amazing !

socbrian commented 4 years ago

I am having a hard time getting my head around how new water gets to the probes. The image here seems like the sensors will get "dirty" water before the pump and then never have pressure because it is before the pump.

0u751d3r commented 4 years ago

seems like the sensors will get "dirty" water before the pump and then never have pressure because it is before the pump.

If you look at the diagram, the "sensor loop" is connected to both the suction AND pressure side of the pump (the latter is after the filter). Water will flow from the higher pressure toward the lower pressure, i.e. it will flow from the pump outlet back to its inlet, so it will always be clean water.

segalion commented 3 years ago

seems like the sensors will get "dirty" water before the pump and then never have pressure because it is before the pump.

If you look at the diagram, the "sensor loop" is connected to both the suction AND pressure side of the pump (the latter is after the filter). Water will flow from the higher pressure toward the lower pressure, i.e. it will flow from the pump outlet back to its inlet, so it will always be clean water.

You are right. Probes are getting "clean" water (after the filter), as it is a recirculation system. Note that this bypass has to be as low as possible to ensure it never runs dry (and probes "caput").

segalion commented 3 years ago

I close this issue as it is solved by @0u751d3r