A MODEL OF STIFFNESS NON-LINEARITY IN FIBROUS MATERIAL DYNAMICS

• Published in: Journal of sound and vibration Vol. 212; no. 2; pp. 375 - 381
• Main Authors: Rice, H.J., Torrance, A.A., Eikelman, G.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 30-04-1998; Elsevier
• Subjects: Acoustics; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Physics; Solid mechanics; Structural acoustics and vibration; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Vibrations and mechanical waves; Fibrous material; Vibrations (mechanical); Numerical methods; Mineral wool; Glass wool; Acoustic absorption; Non linear effect; Experimental study; Aircraft; Structural analysis
• ISSN: 0022-460X; 1095-8568
• DOI: 10.1006/jsvi.1997.1416

In the study of aircraft interior vibroacoustics, the major dissipative mechanism at propeller tone frequencies can be attributed to the dynamic interaction of the thermal insulating layer in the cabin walls with the ambient vibration and acoustic fields. The most popular materials currently being used in these designs are those in the form of glass fiber blankets. At these low frequencies the dynamical behavior of the material is biphasal, incorporating both a fluid and an interacting structural or frame element. This paper proposes a model of the stiffness nonlinearity based on purely physical considerations. The model is shown to agree with dynamical measurements performed on a fibrous material sample used in aerospace applications. (AIAA)