This work uses 2D URANS simulations of an isolated vertical axis turbine (one single turbine with a very low blockage ratio) in order to study the mesh sensitivity of the wake prediction. To that end, four grids are tested and the comparison of the average velocity and turbulence kinetic energy profiles shows that it is better to use a minimum refinement ∆x = ∆y = D/20, with D the turbine diameter. Furthermore, the comparison of velocity and turbulence kinetic energy profiles up to 12 diameters downstream the turbine with experimental data shows the limitations of a 2D model if farms applications are considered.