ACTA AERONAUTICAET ASTRONAUTICA SINICA >
Experimental research of broadband sound power determination in axial fan
Received date: 2014-09-18
Revised date: 2015-03-24
Online published: 2015-04-21
Supported by
National Natural Science Foundation of China (51476134); State Key Laboratory of Aerodynamics Research Fund (SKLA20140201)
It is in urgent need for aircraft engine noise reduction research to find a kind of measurement technique for broadband noise determination in turbomachinery duct to guide the noise reduction design. In this paper, we use wall-flush annularly installed microphone array to measure the noise of axial fan and finally obtain the broadband sound power in duct by means of cross-spectra between measurement signals and reference signal and the application of singular value decomposition (SVD) method. The results show that this experimental technique enables the calculation of not only in-duct transmitted sound power for dominant tones, but also broadband noise over a wide frequency range; this method also helps to distinguishe between sound power transmitted in and against the direction of flow. Broadband noise results confirm that this method behaves fairly robust in loud background noise and hard wall reflection condition.
Key words： broadband noise; mode; array; turbomachinery; axial fan
XU Kunbo , QIAO Weiyang , WANG Liangfeng , TONG Fan . Experimental research of broadband sound power determination in axial fan[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2015 , 36(9) : 2939 -2946 . DOI: 10.7527/S1000-6893.2015.0080
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