CFD-Post Expression transient graph plot takes too long time
 

Hi everyone again,

I ran a Fluent Cell heat simulation and I want to plot the graph of temperature by time step in Excel. For doing this I need to export data.

I'm using CFD-Post and I apply the expression [volumeAve(Temperature)@ locations] for several locations.

I need each time step data of volume average temperature.

But graphploting takes a long time... for one graph takes around 3~4 hours.

Is there any method to accelerate to plot a graph? OR is there a method to export direct expression variables by time step?

This is much better done as the solver runs rather than post processing. In CFX you can use monitor points and Fluent can do it to (but I forget what they call it).

If you want to do it post processing then I would try using a CFD-Post session file to automate the extraction of it.

If depends a lot on the Fluent file format. If it is .h5 or .gz-format, it takes ages to open. CFD-Post likes plain .cas and .dat files best.
Actually, CFD-Post works best with CFX-files, but that is not very help full here, I think.

Also, Fluent saves complete .dat-files with all variables for every time step. As a result, every file is unnecessary large and takes long to load and interpret by CFD-Post.
CFX allows you to only save the variable that you think is relevant. If you are only interested in temperature, you get small .trn-files with only temperature. You understand that this speeds up the loading and interpretation as well.

Great responses,
Just wanted to add a minor thing I found a long time ago. Drive speed matters as well. If you are saving on a spinning disk hard drive, it will take longer than if files are saved to a fast SSD.