CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Post processing of rotational moving reference frame

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 22, 2013, 10:37
Post Post processing of rotational moving reference frame
  #1
New Member
 
B.Rathmann
Join Date: Feb 2013
Location: Germany
Posts: 7
Rep Power: 13
Brathmann is on a distinguished road
Hello, cluerich and clueless readers,

as a beginner to Ansys-FLUENT v14 I try to set up a flow problem with a propeller in a closed hollow cylindrical volume. In the attached pictures you can see the geometry which is one third of the real geometry and the mesh I use for the moment as displayed in FLUENT.
The problem I'm facing for now is that the results I obtained so far are not displayed identically in FLUENT-Results and the Ansys postprocessor CFD-post. You can see the different visualisation by comparing the picture CFDpost to FLUENTresults. I believe to have set all the options identically pretty much, as is hopefully shown in the dialogues next to them. The outer planes are the periodic boundaries and the middle plane is defined by the same 3 points in both cases. Also in CFD-post the streamlines look like there is no real interaction between the two fluidzones (see streamlines.jpg) but as if they pass uneffectedly through the other zone and even the airfoil.

For the setup I chose to use a rotating reference frame and periodic boundaries to set up the problem roughly according to the Ansys 12 Tutorial for Multiple Moving Reference Frame .
The slice with the airfoilshape in it is defined as a rotationally moving frame with the airfoil shaped wall as moving wall at a velocity of 0m/s relative to adjacent cell zone. The contact to the steady fluid volume was set as an interface by default. The right vertical faces are defined as periodic boundaries with the left vertical faces as their shadow walls and the model is a viscous k-epsilon-model. All other settings are basically default.

Do you have any idea why the results are displayed differently? May it be a problem of too little convergence? Or of a mesh too coarse around the contact inface? Or is something wrong in the setup that prevents the mass transfer between the moving and the steady fluid volumes?

Since I have to document my work anyway, I'm thinking to make it a tutorial and post it here, so any hints you give may impove this already in advance.

I will be happy to provide further information if necessary.
Thanks already
Brathmann
Attached Images
File Type: jpg Meshmodel-large.jpg (41.3 KB, 56 views)
File Type: jpg Meshmodel-closeup.jpg (50.8 KB, 47 views)
File Type: jpg Meshmodel-geometry.jpg (36.9 KB, 49 views)
File Type: jpg CFDpost.jpg (92.9 KB, 50 views)
File Type: jpg FLUENTresults.jpg (73.2 KB, 42 views)
Brathmann is offline   Reply With Quote

Old   March 22, 2013, 11:39
Default Streamlines.jpg
  #2
New Member
 
B.Rathmann
Join Date: Feb 2013
Location: Germany
Posts: 7
Rep Power: 13
Brathmann is on a distinguished road
Here is the picture of the so far obtained streamlines mentioned in the initial post.
Attached Images
File Type: jpg streamlines.jpg (80.2 KB, 56 views)
Brathmann is offline   Reply With Quote

Reply

Tags
pbc, post processing, rrf


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
mass flow in is not equal to mass flow out saii CFX 12 March 19, 2018 06:21
moving mesh vs moving reference frame nikolaous FLUENT 0 August 1, 2012 19:46
OpenFoam-1.7.x on Suse 11.2 (64bit) does not compile val46 OpenFOAM Installation 4 August 27, 2010 04:43
G95 + CGNS Bruno Main CFD Forum 1 January 30, 2007 01:34
Concept Behind Moving Reference Frame Lam Main CFD Forum 1 February 27, 2005 13:31


All times are GMT -4. The time now is 06:17.