New theory for the low frequencies non linear acoustic radiation of clamped-clamped beams at large vibrations amplitudes. (2017)

• Record Type: Journal Article
• Authors: Abdelali, H. Moulay; Tiscar, Y.; Benamar, R.
• Is Part Of: Procedia engineering. Volume 199(2017)
• Page Start: 723
• Page End: 728
• Publication Date: 2017
• Subjects: non-linear acoustic radiation -- beam -- forced response -- acoustic radiation indicators -- geometrical non-linearity; Engineering -- Congresses; Engineering -- Periodicals; Engineering; Conference proceedings; Periodicals; 620.005
• DOI: 10.1016/j.proeng.2017.09.028
• Languages: English
• ISSNs: 1877-7058

Abstract

Abstract: Vibrating structures upon a surrounding fluid radiate sound energy. Some of them are desirable like vibrations of musical instruments and many are not like traffic noise. That suggests that the study of its physical mechanism is of importance for the control and reduction of noise. Sound radiation from vibrating structures is also encountered in a number of applications, such as loudspeakers manufacturing, road, rail, marine and airborne vehicles design. The continuous increase of speed in industry and optimization of the weight of pieces go above the domain of validity of the linear theory of structural vibrations, making the classical analytical and numerical tools unable to predict properly the corresponding sound radiation parameters. It is of great interest in such cases to know how the nonlinear vibrations influence the acoustic parameters. In this paper, a new approach is presented for the estimation of the non-linear acoustic radiation of clamped-clamped beams in the neighborhood of the first modes of vibration. Simplified expressions are given for the acoustic indicators using the explicit analytical expressions for the beam non-linear forced response, previously developed. The results allowed the estimation of the effect of non-linearity on the classical acoustic parameters and showed a higher increase in the acoustic indicators, compared with those predicted by the linear theory. This confirms the necessity of taking into account the geometrical non-linearity in order to get accurate estimates of the beams sound radiation at large vibration amplitudes.