Learning Forum

[Jason Moss]

How do I stop a transient simulation once a certain condition is met?   ex:  Inlet pressure has reached a target value.

Thanks in advance!

[Rahul Kumar]

Hello, 

You could use the execute commands to set the conditions. Please see the users guide. 

[Jason Moss]

The command shown below isn't working.  I want the calculation to stop once the inlet pressure decays below 0 bar at the inlet.

Is this the correct way to write the command?  (Inlet zone ID = 6)

(if ( < 0 (pick-a-real "/rep/volume/volume-avg 6 , pressure n")) (set! mstop? #t))

Users guide does not explain how to write scheme programming.

Thanks for your help!

[Rob]

I don't think there is any public Scheme documentation. My approach is to monitor the value of interest and manually stop the model once that point is reached. Otherwise you need a monitor linked to a trigger to cause the convergence criterion to be met. 

[tony.karam2]

Hello,

I am trying to stop the transient simulation when any of the below-described liquid fraction definitions becomes less than 0.1:

• volume-average liquid fraction (I named it "liquid_fraction_va_pcm_all")
• mass-average liquid fraction (I named it "liquid_fraction_ma_pcm_all")

How can I modify the below command to achive my target:

(if ( < 0 (pick-a-real "/rep/volume/volume-avg 6 , pressure n")) (set! mstop? #t))

[tony.karam2]

I guess it can be done using the following commands:

(if ( < 0.8 (pick-a-real "/rep/volume/volume-avg liquid_fraction_va_pcm_all,liquid fraction n")) (set! mstop? #t))

(if ( < 0.8 (pick-a-real "/rep/volume/mass-avg liquid_fraction_ma_pcm_all,liquid fraction n")) (set! mstop? #t))

 

[tony.karam2]

Hello,

I am using the below command which is supposed to stop the transient simulation when air_temp_outlet becomes greater than or equal to 926.5 K. but duing the simulation, Ansys is giving an error message statiting "invalid function". I inserted a "?" after mstop (based on what I saw on some ansys yout tube videos) but I was still getting the same error. Any help would be highly appreciated.

(if((>= (string->number (pick "/solve/report-definitions/compute air_temp_outlet")) 926.5)) (set! mstop #t))

[Rob]

I (and other Ansys staff) can't comment here as the Scheme options aren't covered in documentation and must rely on the wider community for a response.