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stuart23 September 5, 2011 10:59

Initialising Force Monitors
Hi guys

I would like to know if there is a way to create the force-monitor output files without actually running iterations. I have a journal file which includes a monitor using the following TUI code:

/solve/monitors/force/drag-coefficient yes body front_wing rear_wing front_wheel rear_wheel () no yes "CDA-history.dat" no yes 1. 0 0
I also have a gnuplot script that runs every 10 iterations so I can graphically monitor convergence. When my journal is run, Fluent only creates the "CDA-history.dat" file on the first iteration. I then have Fluent run a bash script that uses gawk to extract the column headers and pass them to gnuplot every 10 iterations.
Instead, I would like Fluent to create the dat file without any data in it before I start iterating so I can run gawk once rather than every 10 iterations.

I think it must have something to do with one of the following scheme envvars: (monitor-forces-init) or (monitor-forces). I know this because I can get the GUI window to specify the monitors to pop-up using (gui-monitor-forces 1), and these are the only 2 similar commands from

If anyone has any ideas, I would be extremely grateful. Unfortunately, Fluent Scheme is not well documented, so I have no way of working this out myself.

Thanks in advance

fox000002 September 5, 2011 12:19

Why not use Fluent's plot to monitor it?


You can use following code to create the dat file.


(iterate 0)

stuart23 September 5, 2011 14:04

Excellent, thank you very much Fox.

I cannot monitor Fluent Cortex because my simulations are run on a cluster which I do not have physical access to. I have the option of using VNC through a tunnel, but I enjoy typing white characters in a little black window too much!


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