Power Consumption for Active Acoustic Control of Launch Vehicle Payload Fairings

Vibroacoustics during space vehicle launch has been blamed for as many as 60% of first day satellite failures. At the Air Force Research Laboratory in Albuquerque NM USA, modeling and analysis was performed to determine the feasibility of monolithic piezoceramic actuators and active acoustic control to reduce noise transmission during launch of the OSP launch vehicle with a hypothetical composite fairing. Voltage, power and energy were studied as a function of transmission reduction. The conclusion reached for the case explored in depth was that off-the-shelf monolithic piezoceramic actuators did not have sufficient control authority to reduce noise transmission at realistic sound levels.

Active Acoustic Control of Sound Transmission through Double Walls: Simulation Results

In this paper, the active control of sound transmission through double-panel partitions by inserting acoustic sources in the air gap between the double panels is studied through a computer simulation. The work is an extension of the previous analytical work in which a theoretical framework was developed to reveal the control mechanisms involved in active acoustic control. In this work, a computer simulation based on the theoretical framework is used to assess the control performance under different conditions. It is shown that the property of the radiating panel plays an important role in active acoustic control. The control performance can be improved by increasing the panel damping or decreasing the panel modal density. The reasons for this are discussed.