CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Running, Solving & CFD

[sprayFoam] strange spray formation behaviour

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 23, 2015, 11:41
Default [sprayFoam] strange spray formation behaviour
  #1
Member
 
Pascal Balz
Join Date: Feb 2015
Location: Germany
Posts: 44
Rep Power: 11
pbalz is on a distinguished road
Dear FOAMers,

I want to simulate the injection of liquefied propellant into ambient air using sprayFoam. For some simple tests I started off with the aachenBomb tutorial and some major simplifications.
So at the moment I'm investigating an isothermal case without any breakup/reactions/combustion, etc. The problem I'm facing right now is some really strange spray behaviour which shows up as soon as I change ambient pressure to 1e5 Pa. During the solution process I get some fluctuations in ambient temperature reaching from around 330K to 350K (initial). These are directly related to the spray fluctuations I think.

This has to be some sort of numerical issue I guess. The boundary conditions should be fine as well as the spraycloudproperties. But I'm not getting the error I'm doing here because the spray behaviour is solely dependent on the ambient pressure in my 0-folder.

As soon as I turn on the phaseChangeModel, the spray behaves like it should and forms a nice plume although the evaporation rate is to high and therefore quickly reduces the droplets size.
Thats another task as I'm using the thermophysical properties from the aachenBomb tutorial which are obviously not correct as I need R134a and not heptane. But that shouldn't be the reason for my problem.

So, if anybody has an idea on how to improve the spray formation behaviour to a more phyiscal level... I would be really greatful!

Please let me know if you need any case files.
Attached Images
File Type: jpg strange-spray.jpg (27.7 KB, 26 views)
__________________
Regards,
Pascal
pbalz is offline   Reply With Quote

Reply


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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Strange behaviour when using compressibleInterFoam with constantAlphaContactAngle TobM OpenFOAM Running, Solving & CFD 2 May 11, 2016 06:34
strange pressure behaviour with symmetricPlane boudary condition - interFoam duongquaphim OpenFOAM Running, Solving & CFD 10 August 20, 2013 14:00
Strange residuals behaviour xxxx Main CFD Forum 1 July 13, 2013 14:40
Strange behaviour when using LienCubicKE and NonlinearKEShih hani OpenFOAM Running, Solving & CFD 20 March 6, 2013 10:06
Poiseuille flow: strange behaviour samiam1000 OpenFOAM 6 February 17, 2013 03:31


All times are GMT -4. The time now is 21:35.