Development of a linear acoustic array for aero-acoustic quantification of camber-bladed Vertical Axis Wind Turbine
Document Type
Article
Publication Date
10-1-2020
Abstract
Vertical axis wind turbines (VAWT) are a source of renewable energy and are used for both industrial and domestic purposes. The study of noise characteristics of a VAWT is an important performance parameter for the turbine. This study focuses on the development of a linear microphone array and measuring acoustic signals on a cambered five-bladed 45 W VAWT in an anechoic chamber at different tip speed ratios. The sound pressure level spectrum of VAWT shows that tonal noises such as blade passing frequencies dominate at lower frequencies whereas broadband noise corresponds to all audible ranges of frequencies. This study shows that the major portion of noise from the source is dominated by aerodynamic noises generated due to vortex generation and trailing edge serrations. The research also predicts that dynamic stall is evident in the lower Tip speed ratio (TSR) region making smaller TSR values unsuitable for a quiet VAWT. This paper compares the results of linear aeroacoustic array with a 128-MEMS acoustic camera with higher resolution. The study depicts a 3 dB margin between two systems at lower TSR values. The research approves the usage of the 8 mic linear array for small radius rotary machinery considering the results comparison with a NORSONIC camera and its resolution. These observations serve as a basis for noise reduction and blade optimization techniques.
Keywords
Aeroacoustic, Tip speed ratio, Blade passing frequency, Anechoic chamber, Dynamic stall
Divisions
mechanical
Funders
Universidad de Castilla-La Mancha, Plan Propio de Investigacion, cofinanciadas por el Fondo Europeo de Desarrollo Regional (FEDER) [Grant No: SBPLY/19/180501/000102]
Publication Title
Sensors
Volume
20
Issue
20
Publisher
MDPI
Publisher Location
ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND