Experimental Investigation of Turbulence Effects on Aerodynamics Noise of Channeled NACA 0012 Airfoil

Abstract

Abstract Wind power is rapidly growing worldwide as renewable and clean energy of choice due to its competitiveness in cost and technology advancement. However, as the wind turbines grow, the aerodynamic noise generated from the rotating blades is becoming a major concern that limits the use of wind turbines, especially near residential housing areas. Significant low sleep quality has been reported within 2 km of wind turbine locations that is becoming a problem for wider use of wind energy. Generally, continuous exposure to 85–90 dB noise causes permanent hearing loss in humans. To reduce the aerodynamic noise, channeled blades were implemented in this work to damp the airflow turbulence that causes the aerodynamic noise. Samples of different diameter sizes and angles of inclinations with respect to the cord have been tested and compared to a regular unchanneled blade. Noise measurements have been carried out using low-frequency microphones with frequencies ranging between 0 and 10,000 Hz. While turbulence measurements were performed using a hot-wire anemometer. The measured noise around the blades ranged between 20 and 70 dB up to 600 Hz has been proven to be directly related to turbulence intensity. The best low noise blade design was recommended based on noise measurement.