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Numerical Analysis on the Low Noise Designs of Savonius Wind Turbines by Inducing Phase Difference in Vortex Shedding

와류이탈 위상차를 이용한 사보니우스형 풍력터빈의 소음 저감 설계에 관한 수치적 연구

  • Received : 2013.08.01
  • Accepted : 2013.12.17
  • Published : 2014.03.01

Abstract

In this study, low noise designs for a Savonius wind turbine were numerically investigated. As was reported in our previous study, the harmonic components with a fundamental frequency higher than the BPF were identified as being dominant in the noise spectrum of a Savonius wind turbine, and these components were a result of vortex shedding. On a basis of this observation, an S-shaped blade tip is proposed as a means of reducing the noise generated by small vertical(Savonius) wind turbines. This blade induces phase differences in the shedding vortices from the blades, and thus reduces the noise from the wind turbine. The aerodynamic noise characteristics of the conventional and "S-shaped" Savonius turbines were investigated by using the Hybrid CAA method where the flow field around the turbine is computed using the CFD techniques and the radiated noise are predicted by applying acoustic analogy to the computed flow field data. The degree of noise reduction resulting from the proposed design and its reduction mechanism were confirmed by comparing the predicted noise spectrum of these turbines and the flow characteristics around them.

Keywords

Low Noise Design;Flow Noise;Vertical-Axis Wind Turbine;Vortex;Savonius

References

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Acknowledgement

Supported by : 한국연구재단, 한국에너지기술평가원(KETEP)