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water hammer problem

MOHD FIRDAUS BIN ZAKARIA

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can fluid dynamic model identify water hammer problem?
because i don't know how to run when valve close..
why this software take long time to run? because my model is simple
just pipe Length 3m diameter 0.022m and velocity just 0.01m/s only...(in valve open)
any of you know to do water hammer solution during this COMSOL

2 Replies Last Post May 10, 2010, 6:33 a.m. EDT
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago May 10, 2010, 2:36 a.m. EDT
Hi

no need to mix up the threads with different subjects. I'ts not going to make me resonds more or less quickly, my repsonses rely on 1) available time as I'm doing this on my private time, 2) if I beleive I can give a reply, 3) if I have access to COMSOL.

You were unlucky, none matached this week-end ;)

But still, my reply is vague; I believe YES, because from the moment you can express it as PDE's , its solvable, but I'm not sure what to propose as approach, the question is really what are the physical phenomena required, the hammer effect is a wave propagation effect after an abrupt velocity change, at least in my understanding, and I'm not a fluidic specialist so I'm not feeling well enough informed/trained here. You should look through the litterature to identify the physics needed and then match that against what you have as comsol modules, and then decide how to mix the physics, possibly to add some PDE, if you are missing a module or some physical expressions.

BEst reply so far, but there are other better than me in fluidics around

have fn Comsoling
Hi no need to mix up the threads with different subjects. I'ts not going to make me resonds more or less quickly, my repsonses rely on 1) available time as I'm doing this on my private time, 2) if I beleive I can give a reply, 3) if I have access to COMSOL. You were unlucky, none matached this week-end ;) But still, my reply is vague; I believe YES, because from the moment you can express it as PDE's , its solvable, but I'm not sure what to propose as approach, the question is really what are the physical phenomena required, the hammer effect is a wave propagation effect after an abrupt velocity change, at least in my understanding, and I'm not a fluidic specialist so I'm not feeling well enough informed/trained here. You should look through the litterature to identify the physics needed and then match that against what you have as comsol modules, and then decide how to mix the physics, possibly to add some PDE, if you are missing a module or some physical expressions. BEst reply so far, but there are other better than me in fluidics around have fn Comsoling

MOHD FIRDAUS BIN ZAKARIA

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Posted: 1 decade ago May 10, 2010, 6:33 a.m. EDT
thank you very much (^_^) sir...
thank you very much (^_^) sir...

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