NewTest

\begin{equation} \tag{69}

 \overrightarrow{\Gamma }=\frac{{{T}_{wc}}{{{\vec{u}}}_{wc}}(\Omega _{c}^{3}+{\Omega }'_{c}^{3})+{{T}_{wt}}{{{\vec{u}}}_{wt}}(\Omega _{t}^{3}+{\Omega }'_{t}^{3})}{({{u}_{wc}}+{{u}_{wt}}){{T}_{w}}}

\end{equation}