Learning Forum

[aCVP]

Hi all - I used Fluent to run the simulation and specified "strain rate" as a variable of interest in my solution data export file. However, when using CFD-Post, I cannot find this variable anywhere. I have looked through all of the variables tab. 

How can I access this value in CFD-Post?

Please let me know if this is possible. Thanks!

[Rob]

I've just checked in 2019R2 and it's the third one down in the list variables. 

[aCVP]

The third down from my list is "Velocity.Divergence." How closely related is this to strain rate?

[Rob]

it's not: mine was in the pull down list (on the arrow to select variable), and just below Heat Flux in the Solution section. 

[aCVP]

That's odd. What could be the reason for why it is not showing up? I am using a 19.0 release (academic version). I also selected "Strain Rate" as a variable of interest for my data solution export. Also please note: the strain rate variable is present in the "Solution" tab of fluent and I am able to calculate values. However, I need this variable to be in CFD Post. 

 

Update: This is the strangest solution...but rather than using the "Results" cell in the Fluent module or by adding a new "Results" cell and copying the data over, the strain rate variable will only show up if I import the .cdat (NOT .CAS NOT .DAT) file at the last step into the "Results" cell. I'm not sure why this would make a difference, but it solved my problem - hoping this can help others struggling with this!

[Rob]

cdat is a cut down data file, very useful for CFD Post but useless if you want to restart a Fluent case.  

If you read the case & data (after double checking you did add strain rate to the data quantities) into CFD Post standalone (launch from Start -> ANSYS -> CFD) what happens? 

As an aside we're tending to use Fluent for most post processing with 2019 as it saves opening/closing software and gives us parallel post processing. Fluent's graphics have been improved as part of this. 

[aCVP]

If I read the case & data into CFD Post standalone, the strain rate does not show up (I double checked that the strain rate was added to data quantities). It only shows up when I read in the cdat file. Additionally, only some of my UDSs (added in the data quantities) are visible within CFD Post (but fully accessible/visible in Fluent post-processing). This happens regardless of whether I import the .cdat or full case/data files into CFD Post.

I think I will try to make the switch to Fluent post-processing. The one thing that I like about CFD Post is that it is very easy to switch between time steps - is there an easy way to do this in Fluent post-processing?

 

 

 

 

[Rob]

Not yet....  We just read in different data files at the moment and/or use journals to create images etc.