CFD Online Logo CFD Online URL
Home > Forums > General Forums > Main CFD Forum

exact face values

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

LinkBack Thread Tools Search this Thread Display Modes
Old   June 22, 2009, 11:09
Default exact face values
New Member
Join Date: Jun 2009
Posts: 1
Rep Power: 0
RubenG is on a distinguished road

I'm trying to calculate the exact numerical values of the thermodynamic properties (entropy, enthalpy, mass flow, velocity) on the cell faces. With 'exact' I mean the values which are used by Fluent to solve the navier stokes and turbulence equations.

The reason why I do this, is to perform an exergy analysis. I would like to be able to calculate/visualise the irreversibilities in each cell of the computational domain. To obtain these irreversibilities I need to calculate the flow exergy, which is based on the thermodynamic properties of the fluid on the cell faces.

Thusfar I tried to get these values by means of:
- Applying discretization schemes (first order upwind, second order upwind and central differencing scheme)
After setting the 'right' discretization scheme in the solver, I exported the cell center values to Matlab and tried to reconstruct the cell face values by applying the methods described in the paragraph discretization (Fluent manual).
- Drawing a straight line through the cell
The cell face centers are the intersection points of the line with the cell boundaries. These intersection points can be exported to Matlab.

Unfortunately these methods resulted in negative irreversibilities, which are of course non existing. After that I tried to reconstruct the mass imbalances in Matlab, by exporting and applying the same methods to the cell center values. But that resulted to in large deviations from the values which are displayed when Fluent plots the mass imbalances.

Has anyone an idea how I can obtain the exact cell face values from the cell center values?

RubenG is offline   Reply With Quote


face interpolation exergy

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
[Netgen] Import netgen mesh to OpenFOAM hsieh OpenFOAM Meshing & Mesh Conversion 32 September 13, 2011 05:50
[blockMesh] BlockMeshmergePatchPairs hjasak OpenFOAM Meshing & Mesh Conversion 11 August 15, 2008 07:36
fluent add additional zones for the mesh file SSL FLUENT 2 January 26, 2008 11:55
[blockMesh] Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Meshing & Mesh Conversion 10 April 2, 2007 14:00
[Commercial meshers] Trimmed cell and embedded refinement mesh conversion issues michele OpenFOAM Meshing & Mesh Conversion 2 July 15, 2005 04:15

All times are GMT -4. The time now is 19:55.