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

Track after particle hit the wall.

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

Reply
 
LinkBack Thread Tools Display Modes
Old   October 7, 2013, 06:52
Default Track after particle hit the wall.
  #1
New Member
 
Albert
Join Date: Oct 2013
Posts: 5
Rep Power: 3
Brigido is on a distinguished road
Hi everybody.

I’m doing a steady state simulation with Ansys CFX and using particle transport modeling. I have a problem with the particle track. The track ends a short time before the particle hits an inclined wall (the boundary of the mesh). The wall has a free slip condition.
I want to follow the particle displacement after the impact.

How can I solve this problem?

Thank you!

http://imageshack.us/photo/my-images/809/bpdk.png/

Last edited by Brigido; October 7, 2013 at 07:57.
Brigido is offline   Reply With Quote

Old   October 7, 2013, 17:39
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,929
Rep Power: 85
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
There are many reasons a particle track can terminate - exceed time, distance, integration steps, minimum displacement increment. Have you checked which reason caused this particle track to terminate?
ghorrocks is offline   Reply With Quote

Old   October 8, 2013, 02:59
Default
  #3
New Member
 
Albert
Join Date: Oct 2013
Posts: 5
Rep Power: 3
Brigido is on a distinguished road
Thank you for your answer,

I donít know the reason why particle track terminate. In fact, some tracks arrive to the wall and go out across the outlet, and other tracks donít. This last tracks ends a short time before the particle hits the wall.

I realize the track distance varies according to the residuals. If I stop the solver at 1E-3 I can see a short track across the wall. If I stop the solver at 1E-4 or 1E-5, the problem come back.

Thank you again.
Brigido is offline   Reply With Quote

Old   October 8, 2013, 04:45
Default
  #4
New Member
 
Albert
Join Date: Oct 2013
Posts: 5
Rep Power: 3
Brigido is on a distinguished road
Solved!
The problem was the solver control.

Thanks!
Brigido is offline   Reply With Quote

Old   October 8, 2013, 05:23
Default
  #5
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,929
Rep Power: 85
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
I trust you are not proposing using a very loose residuals convergence critereon is the "solution" to your problem....
ghorrocks is offline   Reply With Quote

Old   October 8, 2013, 05:54
Default
  #6
New Member
 
Albert
Join Date: Oct 2013
Posts: 5
Rep Power: 3
Brigido is on a distinguished road
Quote:
Originally Posted by ghorrocks View Post
I trust you are not proposing using a very loose residuals convergence critereon is the "solution" to your problem....
Of course not. My residual convergence criterion is 1E-5Ö
I changed some parameters of the particle control to solve the problem.

Thanks anyway
Brigido is offline   Reply With Quote

Old   October 8, 2013, 05:56
Default
  #7
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 10,929
Rep Power: 85
ghorrocks has a spectacular aura aboutghorrocks has a spectacular aura aboutghorrocks has a spectacular aura about
I am pleased to hear that, very good.
ghorrocks is offline   Reply With Quote

Old   October 12, 2013, 13:41
Default
  #8
New Member
 
Join Date: Oct 2013
Posts: 2
Rep Power: 0
libbyy is on a distinguished road
Which parameters were causing the termination before reaching the wall?
I am having similar problems in a transient simulation.
libbyy is offline   Reply With Quote

Old   October 15, 2013, 09:14
Default
  #9
New Member
 
Albert
Join Date: Oct 2013
Posts: 5
Rep Power: 3
Brigido is on a distinguished road
Quote:
Originally Posted by libbyy View Post
Which parameters were causing the termination before reaching the wall?
I am having similar problems in a transient simulation.
I increased max. tracking time and max. tracking distance at particle termination control.
Brigido is offline   Reply With Quote

Old   October 28, 2013, 14:33
Default
  #10
New Member
 
Join Date: Oct 2013
Posts: 2
Rep Power: 0
libbyy is on a distinguished road
I will try that, thanks!
libbyy is offline   Reply With Quote

Reply

Tags
track particle hit wall

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
Enhanced Wall Treatment paduchev FLUENT 18 April 11, 2014 07:37
Radiation interface hinca CFX 15 January 26, 2014 18:11
injection problem Mark New FLUENT 0 August 4, 2013 01:30
distance between particle and wall Worth FLUENT 2 June 13, 2009 03:04
Plotting particle wall impact angle (Lagrangian pt Bart Prast CFX 0 January 26, 2009 05:23


All times are GMT -4. The time now is 12:58.