Learning Forum

[cavazquezg]

I'm running a simulation on the biologic reactor of a wastewater treatment plant. This plant has an intermitent aeration cycle, where air goes on and off every 90 minutes. To simulate the biokinetic reactions occurring I've incorporated them as UDFs. Since there are quite many equations to run (17 biokinetic equations), I am doing the simulation in two parts: First I run only the hydrodynamics of the system, and once it is converged, I run the model with the UDFs on top of the "frozen" hydrodynamics.

Since the aeration regime is intermitent, I have two hydrodynamic states: One where aeration is running and another when it's off.

Is there a way to set the model so that automatically changes from one hydrodynamic state to the other every 90 minutes, while the simulation with the UDFs keeps running on top? Right now, I'm doing it manually by stopping and loading the hydrodynamic files every 90 minutes of simulation.

Thanks!

[Rob]

You can use the Execute Commands to trigger TUI commands, but as you're turning things on/off you may need to use Solution Steering or take advantage of the Execute Commands "only once" option. Alternatively a journal with on/off every whatever time steps may be easier to review; just take care with restarts as the journal will restart from the beginning. 

[KoryGlover99]

 

@tunnel rush You just need to add time checking logic in your UDF to automatically turn on/off the aeration mode in 90 minute cycles, so the simulation will run continuously, the hydrodynamics will update according to the aeration status, and the UDF will still operate normally.