Update SU2_CFD/src/solvers/CNSSolver.cpp

Co-authored-by: Pedro Gomes <38071223+pcarruscag@users.noreply.github.com>

Author: TobiKattmann

SU2_CFD/src/solvers/CNSSolver.cpp

@@ -539,7 +539,7 @@ void CNSSolver::BC_HeatFlux_Wall_Generic(const CGeometry *geometry, const CConfi
 
         const su2double Density = nodes->GetDensity(iPoint);
         const su2double oneOnCv = (Gamma - 1.0) / config->GetGas_ConstantND();
-        const su2double Vel2 = GeometryToolbox::SquaredNorm(nDim, &nodes->GetPrimitive(iPoint)[1]);
+        const su2double Vel2 = nodes->GetVelocity2(iPoint);
         const su2double dTdrho = 1.0/Density * ( -Tinfinity + (Gamma-1.0)/Gas_Constant*(Vel2/2.0) );
         const su2double dTdrhoe = (Gamma-1.0)/(Gas_Constant*Density);