This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Zaitsev, V. Articles by Sas, P. Search for Related Content Social Bookmarking                         What's this?

Nonlinear Response of a Weakly Damaged Metal Sample: A Dissipative Modulation Mechanism of Vibro-Acoustic Interaction

Mechanical Engineering Department, Katholieke Universiteit Leuven, Celestijnenlaan 300 B, B-3001, Heverlee, Belgium, Institute ofApplied Physics RAS, 46 Uljanova Str., 603600, Russia

P. Sas

Mechanical Engineering Department, Katholieke Universiteit Leuven, Celestijnenlaan 300 B, B-3001, Heverlee, Belgium

The nonlinear vibro-acoustic response of solid samples containing quite a small amount of defects can be anomalously high in magnitude compared to the case of undamaged intact solids. Functional de pendencies of the nonlinear effects exhibit rather interesting behavior. In this paper, experimental results on nonlinearity-induced cross-modulation of a high-frequency (HF) f = 15 — 30 kHz signal by a low-frequency (LF) F = 20 - 60 Hz vibration in an aluminum plate with a small single crack are reported. Comparison with a reference sample (the identical plate without a crack) has proven that the presence of such a small defect can be easily detected due to its nonlinear manifestations. It is demonstrated that under proper choice of the sounding signal parameters, the effect level can be so pronounced that the amplitude of the modulation side-lobes originated due to the nonlinearity exceeds the amplitude of the fundamental harmonic of the HF signal. Main functional features of the observed phenomena are analyzed, and a new physical explana tion is suggested based on a dissipative mechanism of vibro-acoustic interaction. Results of the numerical simulation of the effect are also presented.

Key Words: Nonlinear response • nonlinear vibro-acoustics • diagnostics • cracks

Journal of Vibration and Control, Vol. 6, No. 6, 803-822 (2000)
DOI: 10.1177/107754630000600601


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?