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Valve, fluid flow question

  1. May 26, 2010 #1
    Hi all,

    Right, this may be a bit hard to explain but I'll do my best. Hopefully attached is a sketch of the situation. The water flows from the tank into the "rigid container" through valve (1). This tank is then heated until the water reaches boiling at which point the thermostatic valve opens draining the water.
    The question is I'm looking for valve (1). It must let the water flow into the container when the container is empty or when the water has drained from the container (due to the hydrostatic pressure exerted on it by the reservoir placed higher than the container) but once the tank is full it must close and definitively separate the water in the tank to the water in the container being treated.
    This may be a simple valve but I'm not really a connoisseur so I was wondering if anyone out there knew what type I'm looking for??

    Thanks in advance

    Attached Files:

  2. jcsd
  3. May 27, 2010 #2


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    Science Advisor

    You need some type of float valve. One that shuts when the water level rises enough to close it.

  4. May 27, 2010 #3
    a simple float type check valve would work well as long as the head pressure was low.
    It is basically a cage with a tapered seat at the top. The ball is boyant in water so as the container fills the ball seals in the seat.
    You could add a calibrated spring under the ball to compensate for higher head pressures.
  5. May 31, 2010 #4
    Brilliant, thanks for you help.
    Just to maybe complicate this a little bit further, instead of a single cubic container it was a long coil pipe. Is there any way to calibrate the valve in order to let the water flow from the pipe through the outlet thermostatic valve while introducing a delay before the inlet water enters? Therefore separating the two streams while inside the pipe.

    Thanks again
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