The surface and interior response of a Cessna Citation fuselage section under three different forcing functions (10-1000 Hz) is evaluated through spatially dense scanning measurements. Spatial Fourier analysis reveals that a point force applied to the stiffener grid provides a rich wavenumber response over a broad frequency range. The surface motion data show global structural modes (less than or similar 150 Hz), superposition of global and local intrapanel responses (proportional 150-450 Hz), and intrapanel motion alone (greater than or similar 450 Hz). Some evidence of Bloch wave motion is observed, revealing classical stop/pass bands associated with stiffener periodicity. The interior response ( less than or similar 150 Hz) is dominated by global structural modes that force the interior cavity. Local intrapanel responses (greater than or similar 150 Hz) of the fuselage provide a broadband volume velocity source that strongly excites a high density of interior modes. Mode coupling between the structural response and the interior modes appears to be negligible due to a lack of frequency proximity and mismatches in the spatial distribution. A high degree-of-freedom finite element model of the fuselage section was developed as a predictive tool. The calculated response is in good agreement with the experimental result, yielding a general model development methodology for accurate prediction of structures with moderate to high complexity.
The vibro-acoustic response and analysis of a full-scale aircraft fuselage section for interior noise reduction
Journal of the Acoustical Society of America ; 117 , 6 ; 3667-3678
2005
12 Seiten, 19 Bilder, 34 Quellen
Article (Journal)
English
British Library Conference Proceedings | 1995
|Vibro-Acoustic Analysis of Aircraft Fuselage Panels using a Periodic SEA Subsystem Formulation
British Library Conference Proceedings | 2008
|Numerical vibro-acoustic modelling of aircraft for the active acoustic control of interior noise
Online Contents | 1994
|