The interaction between wind turbines can cause energy losses, which need to be accurately modeled in order to design energy efficient wind farms. A steady-state Computational Fluid Dynamics (CFD) method can be employed to take into account the mean atmospheric effects on the turbine interaction. However, such a method can suffer from spurious numerical waves when a shallow atmospheric boundary layer (ABL) height relative to turbine tip height is employed, which compromises confidence in the results. In this work, we show that the numerical waves can be removed by excluding Coriolis-induced wind veer through a novel steady-state inflow model of the ABL, for an ABL height that is twice the size of the turbine tip height. The inflow model is shown to be in balance with a large empty successor domain and can therefore be used to isolate the effect of wind veer on the wind farm. When the ABL height is lowered to the turbine tip height small scale numerical waves can reappear, which shows that the wind veer is not the only source of the numerical waves. Wind farm simulations with a laminar version of the ABL inflow model, with and without veer, indicate that the presence of a low (eddy) viscosity can cause numerical instabilities. More research is required to further investigate the origin of the numerical waves and how to remove them in order to perform robust steady-state CFD simulations of wind farms with large wind turbines subjected to shallow ABLs.
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