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FDS User Guide: fix typo

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rmcdermo committed Oct 11, 2017
1 parent 00b7b78 commit ab6be97276eef02fb852bf921d5f6eaf6a319da5
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  1. +1 −1 Manuals/FDS_User_Guide/FDS_User_Guide.tex
@@ -5381,7 +5381,7 @@ \subsection{Radiative Fraction}
\be
\chi_{\rm r} \, \dot{q}''' > 10 \; \hbox{kW/m}^3 \label{clip}
\ee
Elsewhere, hot gases do radiate, adding to the overall radiative loss. Second, FDS applies a correction factor to increase the value of the source term in the radiative transport equation to compensate for the fact that flame temperatures are not resolved on relatively coarse meshes. This correction factor, by default, will only increase, not decrease, the value of the source term. You can change these two default behavior as follows. First, you can force the source term to be modified in all grid cells by changing the 10 in Eq.~(\ref{clip}) to -1 via {\ct QR\_CLIP} on the {\ct RADI} line, in which case the will apply the radiative fraction to the entire domain, not just the cells where combustion occurs. Second, you can allow the source term to increase or decrease in value to achieve the desired {\ct RADIATIVE\_FRACTION} by changing the lower limit of the correction factor, {\ct C\_MIN}, from its default value of 1 to, say, 0.5 on the {\ct RADI} line. The corresponding parameter, {\ct C\_MAX}, limits the correction factor to 100.
Elsewhere, hot gases do radiate, adding to the overall radiative loss. Second, FDS applies a correction factor to increase the value of the source term in the radiative transport equation to compensate for the fact that flame temperatures are not resolved on relatively coarse meshes. This correction factor, by default, will only increase, not decrease, the value of the source term. You can change these two default behavior as follows. First, you can force the source term to be modified in all grid cells by changing the 10 in Eq.~(\ref{clip}) to -1 via {\ct QR\_CLIP} on the {\ct RADI} line, in which case the solver will apply the radiative fraction to the entire domain, not just the cells where combustion occurs. Second, you can allow the source term to increase or decrease in value to achieve the desired {\ct RADIATIVE\_FRACTION} by changing the lower limit of the correction factor, {\ct C\_MIN}, from its default value of 1 to, say, 0.5 on the {\ct RADI} line. The corresponding parameter, {\ct C\_MAX}, limits the correction factor to 100.
\paragraph{Multi-fuel radiative fraction}

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