  Noise generated by wind turbines is significantly impacted by its propagation
in the atmosphere. Hence, for annoyance issues an accurate prediction of sound
propagation is critical to determine noise levels around wind turbines. This
study presents a method to predict wind turbine sound propagation based on
linearized Euler equations. We compare this approach to the parabolic equation
method, which is widely used since it captures the influence of atmospheric
refraction, ground reflection, and sound scattering at a low computational
cost. Using the linearized Euler equations is more computationally demanding
but can reproduce more physical effects as fewer assumptions are made. An
additional benefit of the linearized Euler equations is that they provide a
time-domain solution. To compare both approaches, we simulate sound propagation
in two distinct scenarios. In the first scenario, a wind turbine is situated on
flat terrain; in the second, a turbine is situated on a hilltop. The results
show that both methods provide similar noise predictions in the two scenarios.
We find that while some differences in the propagation results are observed in
the second case, the final predictions for a broadband extended source are
similar between the two methods.
