# how to simulate a VIV of the cylinder in a fluid domian use rigid body solution?

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 May 19, 2013, 01:31 how to simulate a VIV of the cylinder in a fluid domian use rigid body solution? #1 New Member   Ma.L Join Date: May 2013 Location: ShangHai,China Posts: 17 Rep Power: 13 In a fluid domain which contains inlet,outlet,symmetry,and wall, in order to sumilate a cylinder vibration ,how to use rigid body to simulate the cylinder ? That is to say, how to simulate a VIV of the cylinder in this domian? I need your detail and kind answes. I will appreciate your help! Thanks very much!!

 May 19, 2013, 06:04 #2 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,732 Rep Power: 143 Can you draw a picture of what you want to do?

 May 19, 2013, 06:38 #3 Member   rasool Join Date: Apr 2013 Posts: 41 Rep Power: 13 hi are you sure about using rigid body? Maybe you can solve your problem with wall. I suggest you first study carefully totorial (example 23) then ask your questions good luck

May 19, 2013, 07:22
#4
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Ma.L
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Quote:
 Originally Posted by ghorrocks Can you draw a picture of what you want to do?
There is a picture for my simulation in the attachment .
Thank you.
The arrows imply the inlet/outlet boudray, and the left/right faces is the wall, and the up/down faces is the symmetry. The cylinder in the middle of this domain is the rigid body. I want to simulation the movement of this cylinder on condition of the fluid, which is VIV.
Thank you very much.

 May 19, 2013, 07:25 #5 Super Moderator   Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,732 Rep Power: 143 I cannot see any attachments or images.

May 19, 2013, 07:32
#6
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Ma.L
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Quote:
 Originally Posted by rasool motamedi hi are you sure about using rigid body? Maybe you can solve your problem with wall. I suggest you first study carefully totorial (example 23) then ask your questions good luck
OK thank you
before I start my case--simulation of viv of a cylinder,I have study the tutorial(example 22 and 32).In the example 22 and 32,rigid body solution has been used to simulate the movement of rigid,so I want to use the same method to simulate my case.And I will first study carefully totorial (example 23) to look for other solutions.I am a newcomer for the CFX,so I also need you help.
Thank you very much!

May 19, 2013, 07:36
#7
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Ma.L
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Quote:
 Originally Posted by ghorrocks I cannot see any attachments or images.
Sorry I am raw to the CFX.
I have uploaded the image this time.
Thanks!

May 28, 2013, 08:02
#8
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Ma.L
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Quote:
 Originally Posted by rasool motamedi hi are you sure about using rigid body? Maybe you can solve your problem with wall. I suggest you first study carefully totorial (example 23) then ask your questions good luck
hi i have tried the method as the totorial23,but there is a problem.
in the solution cell, after the solution last for some steps,then it indicate a erro that the result file have not been created, so the solution has to be terminated.
have you ever meet this problem?
how to deal with this problem?

 May 31, 2013, 03:24 #9 Member   rasool Join Date: Apr 2013 Posts: 41 Rep Power: 13 hi so much I solved this problem by changing cfx pre step by step and found the problem

May 31, 2013, 07:23
#10
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Ma.L
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Quote:
 Originally Posted by rasool motamedi hi so much I solved this problem by changing cfx pre step by step and found the problem
oh,you are so great.
Did you use the totorial (example 23) or rigid body solution?
If you use the totorial (example 23),could you show me what is the problem and how to solve this problem?
Compared with the totorial (example 23),which step did you change in the cfx pre? maybe this step is the key!
I had been tried to deal with this case for many days,but i alway met some problems that i do not know solve.So i need your help.please..
Thank you very much.

 May 31, 2013, 16:02 #11 Member   rasool Join Date: Apr 2013 Posts: 41 Rep Power: 13 hi o god I am so sorry you must study example 32 no 23 I am realy sorry excuse me I simulated a oscillating blade with sliding mesh and I could use rigid body but used wall boundary. You occured an error that every body use cfx maybe has this problem and I solved my problems in 3 month also your problem is a general problem explane your problem totaly super motherator can help you and I am not expert in cfx

May 31, 2013, 22:15
#12
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Ma.L
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Quote:
 Originally Posted by rasool motamedi hi o god I am so sorry you must study example 32 no 23 I am realy sorry excuse me I simulated a oscillating blade with sliding mesh and I could use rigid body but used wall boundary. You occured an error that every body use cfx maybe has this problem and I solved my problems in 3 month also your problem is a general problem explane your problem totaly super motherator can help you and I am not expert in cfx
i have trid example32 which is similar to example22.
but there is also a problem. the error is that my there is negtive volum and highly distored volum in the domain. i used icem cfd to produce my mesh,and i think the quality of my mesh is good.
in the example32 and 22,it use the subdomain. did you use the subdomain in your case?

 June 1, 2013, 06:57 #13 Member   rasool Join Date: Apr 2013 Posts: 41 Rep Power: 13 hi Yes certainly if your body have moving you must use subdomain WHEN YOU USE SUBDOMAIN you can control move of domain by subdomain with four strategy and I used of specified Location When i occured negative volume my subdomain moving was fuls and my mesh was good can you send your mesh for me www.rasool.mech.esf@gmail.com your mesh is structure or unstructure? You must use unstructure.

 April 14, 2014, 13:44 #14 Senior Member   ok Join Date: Oct 2013 Posts: 346 Rep Power: 13 Dear Rasool, I'm working in the same case. What do you mean by example 22 and 32? If you don't mind I will send you my mesh via email. Kind regards Maimouna

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