Development of a Piezoelectric Active Acoustic Liner for Jet Engine Noise Reduction
Navy SBIR FY2008.2

Sol No.: Navy SBIR FY2008.2
Topic No.: N08-142
Topic Title: Development of a Piezoelectric Active Acoustic Liner for Jet Engine Noise Reduction
Proposal No.: N082-142-0674
Firm: Spectral Energies, LLC
2238 Hunters Ridge Blvd
Dayton, Ohio 45434-7065
Contact: Sivaram Gogineni
Phone: (937) 266-9570
Web Site:
Abstract: Acoustic liners are presently used for attenuating combustion and turbine noise radiated from jet engines. Current acoustic liners are passive by nature. This is a drawback because they are only able to absorb acoustic energy over a limited bandwidth. A possible solution to this drawback is the development of an active acoustic liner. The main advantage of this concept is the ability to tune the acoustic impedance for optimal attenuation at variable operating conditions. In this proposal we outline the development of a piezoelectric acoustic liner that is capable of adapting its attenuation characteristics to the various flight regimes, thus making it a candidate for an active acoustic liner. The liner is active because an electrical excitation is applied to the piezoelectric element causing the porous face sheet to vibrate at a prescribed frequency and displacement. Preliminary results have demonstrated that the active liner can improve the absorption characteristics compared to a passive liner. To build upon these results, a computational model will be developed during Phase I to predict the acoustic absorption properties of the piezoelectric actuator and the perforated liner sheet. Then during option portion of Phase I, the computational model will be further developed and experiments will be run to optimize the liner performance.
Benefits: The technology developed under this SBIR program will have broad applications in commercial and military aerospace industries where aircraft engine noise is an issue in communities around the world. The computational tools and liners developed under this program will also impact the future design of aircraft systems.