The noise radiated by aeroengines or stationary gas turbines is usually reduced by acoustic absorbers, whose efficiency is limited due to the confined length of the inlet and outlet duct sections. Active Noise Control (ANC) was successfully applied to the BPF-tones of a counter-rotating propfan-model, where the tones were generated by interaction of a rotor with inlet disturbances. The best results have been achieved by applying a narrow-band modal control algorithm. At maximum a 32 dB reduction of the downstream propagating rotor coherent sound power level has been achieved. High reductions of transported sound power have been achieved as long as the number of actuators and sensors is not lower than the number of propagating modes in the inlet duct and actuators and sensors are distributed on as many axial positions as radial mode orders are propagating.
Active control of noise from turbomachines - control algorithms and experimental results
Aktive Regelung des Turbomaschinengeräusches - Regelalgorithmen und experimentelle Ergebnisse
2001
6 Seiten, 4 Bilder, 1 Tabelle, 6 Quellen
Aufsatz (Konferenz)
Englisch
Active control of the aerodynamic performance and tonal noise of axial turbomachines
Online Contents | 2003
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