Unites of the transfer rates

Hi,

The simulations of my model differ at different unites of transfer rates. For example, the following are plots for the same variable but for different time scales. Could you please help me to figure out the reason?

[Arthur Goldsipe]

I'm not sure I understand your question. Can you share reproduction steps?

I think you're saying that changing your simulation stop time from 5000 hours to 3e5 minutes (which should be equivalent) changes the results of your simulation. If that's the case, I can think of a couple of possible explanations. But it would be easiest to confirm if you could share a model that reproduces this problem.

[Day]

Yes, correct.

I am sorry I can't share my model because it belongs to a project

Answer 1

[Arthur Goldsipe]

Did you enable UnitConversion for your model? If not, then you will need to manually update your entire model to use consistent time units when changing the sto ptime from hours to minutes.

If you did enable UnitConversion and see this difference, then another common cause of mistakes is incorrectly handling units when calling functions. There's a tip about this on the UnitConversion reference page: "Non-dimensionalize the parameters that are passed to the function if they are not already dimensionless."

Lastly, I suggest reading these simulation troubleshooting tips. In particular, you might want to see if the discrpancy can be removed by disabling AbsoluteToleranceScaling.

[Day]

Thank you so much.

I don't enable the the UnitConversion in my model. However, I checked carefully all the unites of the parameters of the model with my colleague.

I will follow your suggestions, thank you.