论文信息 - Fan Broadband Noise Generation and Propagation

Fan Broadband Noise Generation and Propagation

The two -dimensional (2D) pressure spectra and the modal amp litudes of fan broadband noise, generated due to fan turbulence interacting with downstream stator, are computed using Hanson's recently developed PS -3D source prediction code. The 2D pressure spectra predictions generally compared reasonably well with th e NASA Fan Noise Source Diagnostic Test (SDT) measurements, including the effects of stator sweep and vane count. The predictions show that it is not a good approximation to use equal distribution of energy in the modes for liner design. The predicted br oadband source modal amplitudes are coupled to a duct propagation code to compute the noise propagation in fan exhaust ducts. The relative modal power attenuations due to optimum liner impedance are presented.

D. B. Hanson | Gabriel Zlavog | Yahia A. Abdelhamid | Lian L. Ng

[1] John Premo,et al. Fan Noise Source Diagnostic Test - Wall Measured Circumferential Array Mode Results , 2002 .

[2] M. Nallasamy,et al. Fan Noise Source Diagnostic Test Computation of Rotor Wake Turbulence Noise , 2002 .

[3] Stewart A. L. Glegg,et al. MEASUREMENT AND PREDICTION OF BROADBAND FAN NOISE , 1998 .

[4] Stewart A. L. Glegg,et al. The response of a swept blade row to a three-dimensional gust , 1999 .

[5] Gabriel Zlavog,et al. Statistical Distributions for Acoustic Power of Broad Band Noise in Lined Ducts , 2005 .

[6] Yahia A. Abdelhamid. Acoustic Propagation and Radiation of Fan Noise Sources in Treated Ducts , 2005 .

[7] Donald B. Hanson,et al. Theory for broadband Noise of Rotor and Stator Cascades with Inhomogeneous Inflow Turbulence Including Effects of Lean and Sweep , 2001 .