The noise generated by wind turbines is a factor that must be considered when building a wind farm. As the size of wind turbines continues to increase in the last decades, the aerodynamic sound will gradually become severe and already is the main source of the noise.
Our lab has been engaged in the aeroacoustics research of wind turbines for many years. Regarding the calculation method, in addition to the most common Ffowcs Williams-Hawkings (FW-H) method, our team has further improved and developed the APE-based model of wind turbine noise proposed by the Technical University of Denmark (DTU). This calculation method is able to adapt to a wider range of application scenarios due to its higher accuracy and mesh efficiency with the combination of the actuator line model (ALM).
Especially when predicting the aerodynamic noise propagation of multiple wind turbines in large wind farms or distributed small wind turbines in the urban area, this model has obvious advantages.
Unlike the already-established models in commercial software, the solver of this method is developed based on the open-source CFD software OpenFOAM.
- Spanwise profiles of the mean velocity deficit δU
- at a downstream distance from the turbine of 0.4D at the hub height
- at the rated speed of the NREL 5-MW reference wind turbine
- comparison between ALM/LES and SRM.
- y is normalized by the blade radius R.
- The directivity pattern computed via three methodologies
- ALM/LES+BPM+APE
- SRM+FW-H
- Hamiltonian ray tracing technique proposed by McBride[1]
[1] S. M. McBride. A comprehensive Hamiltonian atmospheric sound propagation model for prediction of wind turbine noise. Master’s thesis, Virginia Polytechnic Institute and State University, 2017.