Salar Haghighatafshar Lunds Universitet Ph.D. Student

Hi,
I already have ArcGIS 10.2.2 installed on my computer but Mike Urban requires an older version i.e. ArcGIS 10.1. I wonder if there is way to keep ArcGIS 10.2.2 which is more recent and have MIKE URBAN installed as well?

Regards,
Salar

Dear Enrico,

I am trying to model steady-state conditions via dynamic simulation i.e. by introducing same flow characteristic everyday during 365 days. I expected to get a straight steady-state condition in the operation so that I could then introduce instantaneous vaiations in the inflow at certain time points.

The problem is that I do not get steady-state results despite I have introduced exactly the same inflow for all the simulation days. Results are still very dynamic with strong fluctuations. 

Do you have any idea how I could solve this problem?

Regards

1- I changed the integrator to "Alg" and I do not get the previous errors.
2- Surprisingly all return flows are "0.00" after the loop-breakers and the hydraulic mass balance of the model does not match. (Return flow are correct at in the flow splitters but then turn to zero after loop-breakers, i.e. return flows are zero in the following flow combiners.
3- Moreover, all the particulate COD (X_??) disappear in the beginning of the process.
4- I am feeling not so good since I am the only one asking questions!
Thanks for taking your time,
/Salar

Dear Enrico,

My investigations show that the biofilm processes cause the problem. The model works fine if I remove both the Trickling Filter and the MBBRs. I have sent the file and the input files to the email address you mentioned above.

I will be very greatful if you could have a look to the model and help me with the problems.

My regards,
/Salar

I am facing two major problems when I run the simulation on VODE (steady-state):

1. It takes tremendously long time to simulate since the steps are extremely little (1E-7 ish).
2. The whole simulation process crashes by the error "Numerical error: CVODE: Integration error: -6" 

Any ideas why it is so and how I can fix them?

Now I have made a new setup. I removed the state variables for Soluable and Particulate COD and connected the output interface variables directly to the measured data (as attached). Is it a problem that I do not have the State varibales for S_COD and X_COD in the fractionation?

https://www.dropbox.com/s/jeklmhdte7qlnr8/Fractionation.jpeg?dl=0

Thanks a lot for your quick response. I suppose I now need to tell the program that X_COD = COD-SCOD and Organic N = TKN-NH4, right? Do I need to add connection with negative weights?

Sorry, but I need to understand the logic behind the connections?

Regards

Hello,

The WWTP I want to model has already measured [i]Soluable COD[/i], [i]NH4[/i] and [i]NOx[/i] in the influent. I wonder how shall I include these input components in the influent fractionation blocks? What and how will be their connection to the other state- and output interface variables?

I have already tried different compositions but I get errors like duplicate parameter names, etc.

I appreciate if anyone could help me on this.

Regards,
/Salar