How to export reverse pathlines data, please?

- April 1, 2019 at 8:06 pm
  
  yg327
  Subscriber
  
  Hi, I am trying to backward particle tracking with fluent, namely tracking particles' pathlines from interested cross section plane backward to upstream inlets. Then I found this discussion, which is quite helpful. /forum/forums/topic/tracing-streamlines-or-pathlines-in-ansys-fluent/
  
  Here is the solution I found: check the "reverse" option in the pathline dialogue box and trace the particles back from the outlet to the inlet. Furthermore, if you check the "write to file" option and then "Fieldview" from the drop down list, you can save the data for all the pathlines in a .fvp file (CSV) which is in ASCII format and very easy and convenient for post processing in MATLAB
  
  I can observe the backward particle pathlines but the exported data are from the interested cross section plane to the downstream outlet rather than expected backward particle tracking from interested cross section plane to upstream inlets.
  
  Does anyone have a clue, please?
  
  Best regards
- April 2, 2019 at 10:09 am
  
  Rob
  Forum Moderator
  
  Which version are you using?
- April 2, 2019 at 10:52 am
  
  yg327
  Subscriber
  
  Hi, I am using 18.2. Thanks
- April 3, 2019 at 11:08 am
  
  Rob
  Forum Moderator
  
  Can you try in a later version? I don't have Fieldview so can't test here.
- April 3, 2019 at 1:17 pm
  
  yg327
  Subscriber
  
  Many thanks, rwoolhou. I believe you pointed the right direction.
  
  I tried with version 18.0 on others' computer. That is right. The exported data show the pathlines backward to the inlet when I clicked reverse. Maybe there is a bug here. The next question is what I should do. I only have the license of 18.2
  
  Thanks a lot.
- April 3, 2019 at 1:42 pm
  
  Rob
  Forum Moderator
  
  If you're using the Student version you can update easily. If you're using the campus licence you may need to talk to IT, unless you're on an independent computer as the campus licence server may not be compatible. Probably worth talking to your supervisor as we're up to 2019R1 now, so you're about 18 months out of date and a lot of useful stuff has gone into the code.
- April 3, 2019 at 3:57 pm
  
  Rob
  Forum Moderator
  
  Just to clarify, pathlines (streamlines) can be displayed in reverse but not exported to Fieldview (which takes flow data). Particle tracks can be exported but don't have a reverse feature, unless I'm missing something!
- April 11, 2019 at 4:45 pm
  
  yg327
  Subscriber
  
  Sorry for the late reply. I asked our IT to install 17.0, and that version can also export reverse pathlines data to Fieldview as 18.0. However, I encountered another problem: some particles are incomplete. When tracking an incomplete particle, I found that the pathline stops near the wall (into loops).
  
  In discrete phase model, I can select particle behavior as reflect in Boundary-wall-DPM. But in pathilnes, what shall I do to let all particles escape rather than incomplete, please?
  
  Thanks a lot.
- April 12, 2019 at 2:59 pm
  
  Rob
  Forum Moderator
  
  If the pathlines stop near the wall then there's not much that you can do. If they hit the wall I think setting it to trap will remove them from the flow.
- April 12, 2019 at 4:32 pm
  
  yg327
  Subscriber
  
  Many thanks. I will try to use discrete phase model to do backward particle tracking