Aerodynamic Noise Characteristics of Horizontal Axis Wind Turbine Blade Using CAA

Abstract

 Abstract—This paper presents the aero-acoustic characteristics of horizontal axis wind turbine blade using computational aero-acoustic. The National Renewable Energy Laboratory (NREL) Phase VI wind turbine blade configuration was considered for the studies. This paper aims at predicting the sound noise generated by rotating wind turbine using unstructured mesh. The LES simulation was used for unsteady transient simulations with hybrid FW-F technique for mid to far-field aero-acoustic sound noise simulation. The volumetric quadrupole noise source was considered to estimate the rotating effect of rotor blade even though the simulation is low Mach number. To perform the numerical simulation for noise characteristics of rotating wind blade, rigid body motion was imposed to the blade surface. The surface total noise term, which includes the thickness and pressure loading terms, and volume quadratic term are obtained efficiently for reference and rotating frame motions respectively. However significant discrepancy of volume and total sound noise level was obtained between reference and rotating motion cases. The unsteady rotating effects of wind blade on the sound noise emission could be simulated well using the process of this study.