An experimental comparison of various configurations of actuators and sensors for active noise and vibration control in turboprop aircraft was completed on a deHavilland DASH-7 fuselage section. Noise control performance was experimentally compared for systems using speakers and structural-based actuators. It was found that at low frequencies, structural-based noise control systems considerably outperform speaker-based noise control systems for reducing interior noise in turboprop aircraft. At higher frequencies, the two forms of actuation provided similar noise reduction performance. In addition, various sensor configurations were investigated for interior noise control. Using a structural-based noise control system, vibration and noise levels are presented for control systems that use accelerometers and microphones as error sensors. It was found that a combination of microphones and accelerometers was necessary to ensure noise and vibration reduction throughout the frequency range studied, and that a frequency dependent sensor weighting can be used to enhance noise control performance. At lower frequencies, the dominant modes of vibration couple directly to the interior acoustics and adding accelerometers to the error sensor array decreased noise reduction performance only slightly. At higher frequencies, adding accelerometers to the error sensor array significantly reduced noise control performance.
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