Menu

Discussion Forum

New Discussion
查找

Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Moving Interior Wall in cdf

Posted 2012年5月15日 GMT-4 12:25 Fluid & Heat, Computational Fluid Dynamics (CFD) Version 4.2a 4 Replies

fhtagn
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi,

I am studying pipe flow, currently in 2D.

I have placed a rigid interior wall, making a certain angle with the direction of flow, inside the pipe. Ideally, I would like it to rotate 'freely' around its first edge (see picture, the red point would be the axis). As of now, I am only using the Laminar Flow module.

By freely, I mean subjected to the flow. How can I achieve this?

1) the freely rotating axis
2) make the mesh follow the interior wall

I am reading this www.comsol.com/support/knowledgebase/970/ and looking for examples.

Thank you

Attachments:

4 Replies Last Post 2012年5月15日 GMT-4 16:03
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2012年5月15日 GMT-4 13:38
Hi

I'm not sure COMSOL 4.2a allows you to simulate a thin wall like that (may be, perhaps someone else has managed) because for a FSi you need from, my knowledge, a domain (a surface in 2D). But you can make it thin and I would end it with two half circular ends to allow a better meshing and fluid separation (avoid right angle corners in CFD but also ACDC ...). Then to give a rotation axis, one way is to make a hollow cylinder and apply a roller structural BC or apply a weak equation to enforce a rotation

--
Good luck
Ivar
Hi I'm not sure COMSOL 4.2a allows you to simulate a thin wall like that (may be, perhaps someone else has managed) because for a FSi you need from, my knowledge, a domain (a surface in 2D). But you can make it thin and I would end it with two half circular ends to allow a better meshing and fluid separation (avoid right angle corners in CFD but also ACDC ...). Then to give a rotation axis, one way is to make a hollow cylinder and apply a roller structural BC or apply a weak equation to enforce a rotation -- Good luck Ivar
fhtagn
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2012年5月15日 GMT-4 15:53
Thank you for your reply

> But you can make it thin and I would end it with two half circular ends to allow a better meshing and fluid separation (avoid right angle corners in CFD but also ACDC ...)

Yes, maybe that will have to do (and thank you for the tips). I have used fillet (the circular ends, right?) and it bends the obstacle nicely. However, I want the obstacle to be rigid, so I guess I'd have to mess with the Young modulus. And add a constraint to a point?

I found this: www.comsol.com/community/forums/general/thread/15286/#p41764

Can someone point me in the right direction? My obstacle's movement will also come from an external ODE, I "just" don't know how to move the obstacle mid simulation.
Thank you for your reply > But you can make it thin and I would end it with two half circular ends to allow a better meshing and fluid separation (avoid right angle corners in CFD but also ACDC ...) Yes, maybe that will have to do (and thank you for the tips). I have used fillet (the circular ends, right?) and it bends the obstacle nicely. However, I want the obstacle to be rigid, so I guess I'd have to mess with the Young modulus. And add a constraint to a point? I found this: http://www.comsol.com/community/forums/general/thread/15286/#p41764 Can someone point me in the right direction? My obstacle's movement will also come from an external ODE, I "just" don't know how to move the obstacle mid simulation.
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2012年5月15日 GMT-4 15:56
Hi
you could try with the Rigid Connector on your structural domain, that will enforce it to be "rigid"

--
Good luck
Ivar
Hi you could try with the Rigid Connector on your structural domain, that will enforce it to be "rigid" -- Good luck Ivar
fhtagn
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2012年5月15日 GMT-4 16:03
Again, thank you.

(had just found this www.comsol.dk/community/forums/general/thread/13559/#p36289)

Another day, another thing to explore in COMSOL...
Again, thank you. (had just found this http://www.comsol.dk/community/forums/general/thread/13559/#p36289) Another day, another thing to explore in COMSOL...

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content