steady-state and transient simulation

stefan85r · July 25, 2012, 08:52

Hi.
At the moment I am simulating the valve (picture) stationary. Ansys WB 14
The Flap is rotating round a point"drehpunkt". The value "h" varied between closed flap and 100 mm.
Diameter of the cross-sectional area is 500 mm.
Now I would start an transient simulation. I generated several meshes in ICEM CFD with different opening highs.
My consideration: I start the simulation stationary with a minimum opening high (1mm ?!), after I add other meshes (h=15mm, 55mm, 100mm).
Is that possible? Could that be correct?!
As results I need the massflow and force on the flap in space of the different highs.
Does anyone have a document or can help me?
Thanks!!

ghorrocks · July 25, 2012, 19:37

The steady state models are easy, just generate meshes at the different openings and run it.

The transient is trickier. You have two options:
1) Use dynamic remeshing to do remeshing as the valve opens. There are tutorials on how to do this on the ANSYS customer site.
2) Use an immersed solid for the valve cap. Much easier to implement but makes some approximations about the flow and cannot handle all flow regimes.

stefan85r · July 27, 2012, 09:13

I have done the steady state simulations, thx.
¨
But I don't know how I can add the several mesehen to realize the flap-opening..

ghorrocks · July 28, 2012, 08:54

Did you read my post? I gave two options for modelling this as a transient. There are probably other options as well, but these two come to mind.

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July 25, 2012, 19:37		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,852 Rep Power: 144	The steady state models are easy, just generate meshes at the different openings and run it. The transient is trickier. You have two options: 1) Use dynamic remeshing to do remeshing as the valve opens. There are tutorials on how to do this on the ANSYS customer site. 2) Use an immersed solid for the valve cap. Much easier to implement but makes some approximations about the flow and cannot handle all flow regimes.

July 27, 2012, 09:13		#3
stefan85r New Member stefan Join Date: Jul 2012 Posts: 11 Rep Power: 14	I have done the steady state simulations, thx. ¨ But I don't know how I can add the several mesehen to realize the flap-opening..

July 28, 2012, 08:54		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,852 Rep Power: 144	Did you read my post? I gave two options for modelling this as a transient. There are probably other options as well, but these two come to mind.