CFD Online Discussion Forums - WSGG radiation model

In the WSGGM model, the emissiity weighting factors $\alpha_{\varepsilon}$ are expressed as a polynomial function of temperature of order $N_{g}$ , i.e.

$\alpha_{\varepsilon,i}(T)=\sum_{j=0}^{N_{g}}b_{\varepsilon,i,j}T^{j}$

where $N_{g}$ is the number of gray gases (3 in the work of Smith et al. 1982). For example in Table 1, for a mixture with

you have

$\alpha_{\varepsilon,1}(T)=6.508\times 10^{1} - 5.551\times 10^{4}\cdot T + 3.029\times 10^{7}\cdot T^{2} - 5.353\times 10^{11}\cdot T^{3}$
$\alpha_{\varepsilon,2}(T)=-0.2504\times 10^{1} + 6.112\times 10^{4}\cdot T - 3.882\times 10^{7}\cdot T^{2} + 6.529\times 10^{11}\cdot T^{3}$
$\alpha_{\varepsilon,3}(T)=2.718\times 10^{1} - 3.118\times 10^{4}\cdot T + 1.221\times 10^{7}\cdot T^{2} - 1.612\times 10^{11}\cdot T^{3}$

I believe if you read Fluent User Manual you can easily type above expressions in the dialog box of the custom field expression, create such fields and later postprocess them (contours, lines, probes, etc...)

Then, what else you want to plot? 1) the absorption coefficients $k_{i}$ ? or 2) the

-th emissivities $\varepsilon_{i}$ ?
If its the first case, they are already shown in Table 1 (2nd column). If its the second, you can use Eq. (1) to create corresponding field expressions for each $\varepsilon_{i}$