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05-27-2020
09:04 PM

05-27-2020
09:04 PM

Hi everyone,

In my reactor design with Mathcad, I am getting an error in "tend" part of the design which says "divide by zero" when I click on "tend" and therefore I am not able to see the changes in temperature and conversions with the changes in volume. Although I checked several times to see whether there is any zero value in the denominators or not, I couldn't find any. I would be super happy if you can help me with it. You can find the file and the photos attached in the mail.

Thank you for taking your time.

Selim

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05-28-2020
05:27 AM

05-28-2020
05:27 AM

You have a divide by zero error here:

You set T(0) = 0 in your solve block. I suspect you should be using absolute temperature, so T(0) = non-zero value.

Alan

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05-28-2020
05:27 AM

05-28-2020
05:27 AM

You have a divide by zero error here:

You set T(0) = 0 in your solve block. I suspect you should be using absolute temperature, so T(0) = non-zero value.

Alan

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05-28-2020
12:59 PM

05-28-2020
12:59 PM

Re: Divide by zero error in tend

Hi,

I got the results I am looking for after changing T(0)=0.

Thank you so much Alan 🙂

Best regards,

Selim

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05-28-2020
09:43 AM

05-28-2020
09:43 AM

Re: Divide by zero error in tend

Hi,

By keeping X2 = 1 and T = const, as X1 varies between -1 and 1, the function R2 has discontinuities:

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05-28-2020
01:54 PM

05-28-2020
01:54 PM

Re: Divide by zero error in tend

Hi,

Thank you for such a detailed analysis it seems at some point we are getting errors due to the discontinuities in R2 and since X1 goes to -1. Maybe finding areas that works for solution can be a better approach. In anyway thanks a lot for taking your time on my problem, I really appreciate it 🙂

Best Regars,

Selim