What are dynamics for sudden water flow stoppage?

[mrelet]

I test swimming pool drains-- sort of. I block the drain with a foam pad after establishing constant flow gpm. I take data and the pressure/time trace shows an initial sharp drop and then an oscillatory form on top of a decay back towards the pressure of the water head of the tank. Longer suction pipe lengths have longer periods.

Does anyone know if this can be modelled as a mass-spring damper system where the mass is the incompressible flow and the spring and damper properties are mainly in the foam? Would you know a good source of instruction/information?

 

[IRstuff]

sounds like water hammer

TTFN

 

[GregLocock]

You'll find the pipe elasticity is an important factor.

Cheers

Greg Locock

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