## derive residual exact calculation

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daniele
Posts: 82
Joined: Wed Feb 01, 2017 11:42 am

### derive residual exact calculation

Hello,

I looked for the posts on this subject, but could not find a precise answer: what is the actual meaning of the "derive" residual and how is it calculated? Is it the lhs minus rhs of the equation? More exactly max(lhs - rhs) among all cells?
I have a converged calculation, with derive residuals all lower than 10^-3, except for the enthalpy one which is as high as 10^+5.
I have a source term of 10^8 W (total source term integrated on the calculation domain) for the enthalpy equation, I would like to know if the 10^5 derive residual can be acceptable considered the order of magnitude of the source term.
Does it mean that I have a cell where lhs minus rhs of the enthalpy equation gives 10^5 W?

Many thanks in advance.

Best regards,

Daniele