Temperature at specific time steps
 

Hi all,

I am trying to get a Expression done that gives me the difference of the last 3 or 4 Temperature peaks in a transient simulation, and I want to use this expression in the Interrupt Control.

I know at what times the peaks are, so I can get the time step numbers. I can also create a script to get those values, but only after the simulation run is finished.

What I need is a expression like:
0.01 [K] > MaxT@Timestep(81) - MaxT@Timestep(61)

I know "@Timestep(81)" doesn't exist, but I am looking for something that works like that.

Basically my simulation has periodic peak points. Those peak points are settling down at a certain temperature. When this temperature at the peaks has a change of less then 0.01 [K] I want to interrupt the simulation.

Hope somebody can help me there???

Regards,
Alex
http://dl.dropbox.com/u/15545838/peaks.jpg

CFX Expressions cant remember prior values while in solution (you can get fancy and delay updating a variable so that you can get current timestep value - previous timestep value numbers but that is about the extent you can do in CEL). You will need user fortran.

Thanks for the reply.

I haven't used Fortran yet, but looks like I need to get into it. Am I assuming right, that I can play with variables and manipulate the simulation process?

You can do pretty much anything you like with user fortran. But be warned, it is not straight forward.

If you want to implement a simple function as you describe you could do it using a separate file (maybe a cron job) which monitors the output of your monitor point and if triggered runs the cfx5stop command. I suspect this will be much easier to implement than the fortran option.