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Active control of fan noise-feasibility study. volume 2: canceling noise source-design of an acoustic plate radiator using piezoceramic actuators
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Rajiyah, H. Pla, F. G. |
| Copyright Year | 1995 |
| Description | The feasibility of using acoustic plate radiators powered by piezoceramic thin sheets as canceling sources for active control of aircraft engine fan noise is demonstrated. Analytical and numerical models of actuated beams and plates are developed and validated. An optimization study is performed to identify the optimum combination of design parameters that maximizes the plate volume velocity for a given resonance frequency. Fifteen plates with various plate and actuator sizes, thicknesses, and bonding layers were fabricated and tested using results from the optimization study. A maximum equivalent piston displacement of 0.39 mm was achieved with the optimized plate samples tested with only one actuator powered, corresponding to a plate deflection at the center of over 1 millimeter. This is very close to the deflection required for a full size engine application and represents a 160-fold improvement over previous work. Experimental results further show that performance is limited by the critical stress of the piezoceramic actuator and bonding layer rather than by the maximum moment available from the actuator. Design enhancements are described in detail that will lead to a flight-worthy acoustic plate radiator by minimizing actuator tensile stresses and reducing nonlinear effects. Finally, several adaptive tuning methods designed to increase the bandwidth of acoustic plate radiators are analyzed including passive, active, and semi-active approaches. The back chamber pressurization and volume variation methods are investigated experimentally and shown to be simple and effective ways to obtain substantial control over the resonance frequency of a plate radiator. This study shows that piezoceramic-based plate radiators can be a viable acoustic source for active control of aircraft engine fan noise. |
| File Size | 56533117 |
| Page Count | 150 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19960003376 |
| Archival Resource Key | ark:/13960/t7np70k6p |
| Language | English |
| Publisher Date | 1995-03-01 |
| Access Restriction | Open |
| Subject Keyword | Acoustics Actuators Sound Waves Jet Aircraft Noise Engine Noise Noise Reduction Aerodynamic Noise Piezoelectric Ceramics Optimization Tuning Resonant Frequencies Beams Supports Turbofan Engines Sound Generators Active Control Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
