Flow topology and acoustic emissions of trailing edge serrations at incidence

被引：1
作者：
Carlos Arce León
Daniele Ragni
Stefan Pröbsting
Fulvio Scarano
Jesper Madsen
机构：
[1] Delft University of Technology,Department of Aerospace Engineering
[2] LM Wind Power,Aerodynamics and Acoustics Group
来源：
Experiments in Fluids | 2016年 / 57卷
关键词：
Particle Image Velocimetry; Particle Image Velocimetry Measurement; Suction Side; Pressure Side; Reynolds Shear Stress;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
The flow past a NACA 0018 airfoil with sawtooth trailing edge serrations has been investigated using stereoscopic particle image velocimetry (PIV). The serration flap angle and airfoil incidence are varied in order to study the effect of secondary flow establishing between the suction and pressure sides of the serrations. The flow topology around the serrations is inferred from the analysis of time-averaged streamlines close to the airfoil surface and from the wall-normal flow velocity in between serrations. Additional PIV measurements with a plane in cross-flow highlight the formation of streamwise vortex pairs. The flow behavior is further characterized in terms of its turbulence statistics. Noise emissions are measured with an acoustic phased array in combination with beamforming. The serrations are found to be effective in reducing noise, and their application is studied for different degrees of airfoil incidence and serration flap angle.
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