Right option is (a) \(\frac{\sqrt{\overline{\vec{V}^{‘}.\vec{V}^{‘}}}}{\sqrt{\vec{V}.\vec{V}}}\)
Easiest explanation: The turbulence intensity which is used to get the k and ε-values for the inlet boundary conditions is
\(T_i=\frac{\sqrt{\overline{\vec{V}^{‘}.\vec{V}^{‘}}}}{\sqrt{\vec{V}.\vec{V}}}\)
Where,
\(\vec{V}\) → Velocity vector.