CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

Boundary condition in an axisymmetric 2D flow

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   February 12, 2008, 17:10
Default Boundary condition in an axisymmetric 2D flow
  #1
jinwon park
Guest
 
Posts: n/a
As I posted before, I am solving axisymmetric 2D underwater explosion. The 200*200cm domain in r and z coordinates corresponds to the fluid domain consisting of water and explosive gas. The bottom is the rigid wall to obtain the reflecting of strong shock wave.

The initial condition is illustrated by the situation that a half circle with raidus 16cm modeling gas bubble is located at x=0cm y=20cm above the rigid bottom plate. As time goes, high pressure impinges against the rigid bottom and wave is reflected.

I initially set the bottom and the left wall as rigid boundaries. I wonder if such boundary impositions in axisymmetric flows were right. Could anyone advice me how to imply axisymmetric flow motions?

Thanks in advance.
  Reply With Quote

Old   February 12, 2008, 19:59
Default Re: Boundary condition in an axisymmetric 2D flow
  #2
Ertan Karaismail CFD&AMP
Guest
 
Posts: n/a
Is the bottom wall axis of symmetry? If so, I think you should use symmetry boundary condition instead of rigid wall.. Sorry if I got you wrong..
  Reply With Quote

Old   February 12, 2008, 20:02
Default Re: Boundary condition in an axisymmetric 2D flow
  #3
jinwon park
Guest
 
Posts: n/a
Yes. Bottom wall axis is symmetric.If so, what is the symmetric boundary condition?

I set the y-dir velocity at the bottom as zero and the x-dir velocity along the symmetric axis as zero.

Could you give me idea how to define symmetric B.C?

Thanks in advance!
  Reply With Quote

Old   February 12, 2008, 22:15
Default Re: Boundary condition in an axisymmetric 2D flow
  #4
Ertan Karaismail CFD&AMP
Guest
 
Posts: n/a
Taking centerline (x-axis at r=0) as the symmetry axis, you can set du/dr=0 and v=0 on the centerline. But this condition does not imply that symmetry axis is a rigid wall as you said in your first post.

HTH
  Reply With Quote

Old   July 23, 2012, 13:55
Default how did you create your shockwave??
  #5
Member
 
Mike
Join Date: Jun 2012
Posts: 55
Rep Power: 5
dreamchaser is on a distinguished road
jinwon park and Ertan Karaismail CFD&AMP ,

I am working on a similar simulation.
I am trying to create an underwater shockwave using a heat source.
I want to see how the shock reflects off of the reflecting walls.

How did you create your shockwave??
I'm using a heat source but I'm not getting any good results.

I would really appreciate any kind of help you can provide.

thanks
dreamchaser is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wind turbine simulation Saturn CFX 34 October 16, 2014 05:27
inlet velocity boundary condition murali CFX 5 August 3, 2012 08:56
Swirling flow as a boundary condition hami9293 FLUENT 0 November 2, 2010 08:09
mass flow in is not equal to mass flow out saii CFX 2 September 18, 2009 08:07
Mass flow boundary condition vivian Main CFD Forum 0 April 10, 2006 23:32


All times are GMT -4. The time now is 10:33.