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pressure distribution in rotating cylinder

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Hii,

I am a beginner in COMSOL. I want to model a rotating cylinder filled with air. The surroundings of cylinder is air as well. I want to see the pressure distribution inside the cylinder. The solution is converging and displays the results but I have doubt on its accuracy. Can someone check my model

A major doubt I have is about the geometry: I have placed an air cylinder inside the plastic cylinder...is it right way to model the air inside the plastic cylinder. Should I use the contact pair definition to attach both of them.

I am attaching my model here. Can explain it further if someone could help


2 Replies Last Post 2010年11月23日 GMT-5 05:16
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2010年11月22日 GMT-5 15:15
Hi

I beleive your model is slightly complex to start with. First of all it depends on what you want to mode, is it the cetrifugal force acting on the fluid, or a transient analysis of the fluid starting to rotate induced by a non-slip flui-wall inteaction ? And is the air around (outside the plexi) really useful ?

You can in principle start just with a cylinder, static and say the reference is rotating at a rotational speed w0, which induces a body load on the fluide. Or you use the rotating domain.

Furthermore, I would not use "contact" as these are rather for mechanical (structural) contact. An identity pair is sufficient for the rotating boundary. Check the doc

--
Good luck
Ivar
Hi I beleive your model is slightly complex to start with. First of all it depends on what you want to mode, is it the cetrifugal force acting on the fluid, or a transient analysis of the fluid starting to rotate induced by a non-slip flui-wall inteaction ? And is the air around (outside the plexi) really useful ? You can in principle start just with a cylinder, static and say the reference is rotating at a rotational speed w0, which induces a body load on the fluide. Or you use the rotating domain. Furthermore, I would not use "contact" as these are rather for mechanical (structural) contact. An identity pair is sufficient for the rotating boundary. Check the doc -- Good luck Ivar

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Posted: 1 decade ago 2010年11月23日 GMT-5 05:16
Thanks Ivar, Yes I am interested in centrifugal force acting on fluid. I have removed the outer air block , i think it is not that necessary . The modified model is showing some believable results. I am trying it to improve it a bit more
Thanks Ivar, Yes I am interested in centrifugal force acting on fluid. I have removed the outer air block , i think it is not that necessary . The modified model is showing some believable results. I am trying it to improve it a bit more

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