@article {Wang:2020:0736-2935:2411,
title = "Experimental study on instability tonal noise reduction using trailing edge gradient porous materials",
journal = "INTER-NOISE and NOISE-CON Congress and Conference Proceedings",
parent_itemid = "infobike://ince/incecp",
publishercode ="ince",
year = "2020",
volume = "261",
number = "4",
publication date ="2020-10-12T00:00:00",
pages = "2411-2418",
itemtype = "ARTICLE",
issn = "0736-2935",
url = "https://ince.publisher.ingentaconnect.com/content/ince/incecp/2020/00000261/00000004/art00048",
author = "Wang, Yong and Lai, Qing-Ren and Liang, Yong and Song, Yu-Bao and Zheng, Xie",
abstract = "Instability tonal noise is an important mechanism for airfoil self-noise generation from the trailing edge at low Reynolds number flow under free field conditions. In this paper, an experimental study on the reduction of airfoil instability tonal noise is presented. The experiment in
the 0.55 m \texttimes 0.4 m aeroacoustic wind tunnel was performed on a set of NACA 0012 airfoils with trailing edge gradient porous materials. Those materials feature a piecewise gradual change in pores per inch (ppi) between one region and another at the trailing edge. The acoustic measurement
showed that a noticeable tonal noise reduction (up to 14 dB overall sound pressure level) can be achieved. Moreover, a preliminary parameter study demonstrated that tonal noise reduction enhances when the porous treatments gradually sparsely transiting from aluminum main body to downstream
air flow, whereas diminishes with increasing flow speeds.",
}