Noise and Vibration Control Engineering: Principles and Applications

Abstract

Lord Corp has developed a combination of three technologies to help solve problems of aircraft cabin noise and vibration. Lord's NVX systems combine active and passive noise and vibration control techniques to increase cabin comfort to levels previously unattainable. The technologies are distinguished by the actuators and sensors used for control. Active noise control uses microphones to detect cabin sound, and speakers to eliminate it. Active structural control uses inertial actuators which monitor and control the vibration of the fuselage which, in turn, reduces noise. Active isolation control includes active mounts which control noise and vibration at the interface between disturbance sources and the fuselage. Microphones and accelerometers are used to monitor noise and vibration in both active isolation control and active structural control.