The heat-diffusion model of Nagano has been reformulated by Rochhausen [43] . This version is implemented. Deviating from the paper, the diffusion for \(k_\theta\) and \(\omega_\theta\) is given by:

\begin{eqnarray} \parfrac{}{x_j} \left[ \frac 1 {c_p} \left( \frac \lambda {\sigma_{k, L}} + \frac{\lambda_T}{\sigma_k} \right) \parfrac{k_\theta}{x_j} \right] *\\ \parfrac{}{x_j} \left[ \frac 1 {c_p} \left( \frac \lambda {\sigma_{\omega, L}} + \frac{\lambda_T}{\sigma_\omega} \right) \parfrac{\omega_\theta}{x_j} \right] *\end{eqnarray}

The constants are set to:

Constant	Value
\(\sigma_{k, L}\)	0.4
\(\sigma_{k}\)	2.0
\(\sigma_{\omega, L}\)	0.4
\(\sigma_{\omega}\)	2.0