Luís Roque Silva Lopes

Is it through the top-leval interface variables, that I solve this problem?

Good afternoon
I have an activated sludge system with surface aerators, where the aerators' input power is indicated to maintain the levels (concentration) of actual OD in the ASU tank.

I make the correct adjustment of the aerators' input power, to obtain OD levels in the ASU tank.

However I noticed that OD levels change during the parameter calibration experience, and also when I change the incoming fractionation of the effluent.

Question: Is there any way to enter the OD levels in the ASU tank with a fixed value?

Thank you for your help

I have an activated sludge system (ASU) with 4 biological reactors that have surface aerators.

I intend to calibrate the parameters (YH, Ks; umxH, YA, umaxA), which represent the 4 surface aerators that make up the system.

  In other words, I do not want results for each ASU, but rather a global result for the 4 biological reactors.

Now it is working, I have changed the step size field to a value other than zero (= 0,3)

Thank you

In the property analysis sheet I have:
Auto-scale: is selected;
Step size = 0;
Solver optimizer of the Simplex type

good afternoon
I am calibrating the following parameters of the activated sludge model: YH, Ks and aH for heterotrophic biomass and YA and umaxA for autotrophic biomass.

The input data entered were the daily mean values of: TKN, COD, water and BCOD.

I intend to calibrate the parameters considering the mean difference between the measured and simulated values of the treated effluent (TKN and COD).

The inserted TKN and COD data of the treated effluent in the property analysis sheet in the parameter estimation experiment (steady-state conditions) corresponds to a series of data of daily values for 90 days.

The problem that arises is that the values of the calibrated parameters are equal to the initial values of the same (indipendently of the initial values assumed by the parameters).

What could be happening?

Thank you, Luís Lopes

Thank you very much

Yes, I mean calibration of the parameters, for three different temperatures. And the kinetic parameters to be calibrated are only u_maxH (specific maximum growth rate for heterotrophic biomass) and Ks for heterotrophic biomass.

Another question, when I change the temperature value, does the kinetic parameters automatically change to that temperature?

Best regards,

Luís Lopes

First of all the aerator that are being used in the project is of "surface aeration model" type (this type of aerator asks to insert the water's temperature).

In the tank of the aeration(ASU)  there is a field representing the temperature of the activated sludge. If I set that field to a temperature value that is equal to temperature of the aerator's block an error occurs(related to input file or the evaluation of the upper/lower bound ).
My first question is, how can I solve this problem?

The second question is, the modelling is will be performed for 3 different periods(each one of them with different temperature values). Should I perform the calibration of the parameters for each one of the periods, or it is enough to make only one calibration?

Best regards,

Luís Lopes