@article {Geyer:2019:1610-1928:109,
title = "Reduction of Turbulence Interaction Noise Through Airfoils With Perforated Leading Edges",
journal = "Acta Acustica united with Acustica",
parent_itemid = "infobike://dav/aaua",
publishercode ="dav",
year = "2019",
volume = "105",
number = "1",
publication date ="2019-01-01T00:00:00",
pages = "109-122",
itemtype = "ARTICLE",
issn = "1610-1928",
url = "https://www.ingentaconnect.com/content/dav/aaua/2019/00000105/00000001/art00014",
doi = "doi:10.3813/AAA.919292",
author = "Geyer, Thomas F. and Lucius, Andreas and Schr{\"o}dter, Marcus and Schneider, Marc and Sarradj, Ennes",
abstract = "With the aim of reducing turbulence interaction noise of axial fans, a wind tunnel study was performed on airfoils equipped with a flow permeable leading edge. The leading edges were realized as bulk materials with round pores and manufactured using rapid prototyping. The inflow turbulence
was generated by a turbulence grid. Acoustic measurements were performed using microphone array technology, while simultaneously the aerodynamic performance was captured with a wind tunnel balance. In order to provide insight on the flow phenomena at the perforated leading edges, a RANS simulation
was performed. The results show that a noticeable noise reduction up to 8 dB is possible in a frequency range between 1 kHz and 4 kHz, while for leading edges with large pores additional high frequency noise is generated. At low geometric angles of attack from 0\textdegree to 8\textdegree, the aerodynamic
performance of the modified airfoils is the same as for a reference airfoil with solid leading edge. At higher angles of attack the perforated leading edges lead to an aerodynamic penalty.",
}