The aim of the thesis is to carry out high fidelity computational fluid dynamics, CFD, simulations on the DTU 10MW wind turbine in order to understand (1) what is the best way for generating grids, (2) what is the optimum turbulence model to mimic the aerodynamics behind the turbine and (3) what are the effects of the cell size extruded from the blade, thus on the use of wall functions, on the performance computation. The first part of the thesis deals with several studies done on the NACA 0012 airfoil profile. The latter were done with the aim of familiarizing with the solver Open- Foam and with the grid generator Pointwise and of shallowly forecast, from the airfoil, what the behaviour of the turbine simulations would be by using similar settings.