On the attenuation of vibration using a finite periodic array of rods comprised of either symmetric or asymmetric cells. (27th October 2021)

• Record Type: Journal Article
• Authors: Carneiro Jr, J.P.; Brennan, M.J.; Gonçalves, P.J.P.; Cleante, V.G.; Bueno, D.D.; Santos, R.B.
• Is Part Of: Journal of sound and vibration. Volume 511(2021)
• Publication Date: 2021-10-27
• Subjects: Periodic structures -- Finite structure -- Asymmetric structure -- Attenuation band estimation -- Transfer matrix method; Sound -- Periodicals; Vibration -- Periodicals; Son -- Périodiques; Vibration -- Périodiques; Sound; Vibration; Periodicals; Electronic journals; 620.205
• DOI: 10.1016/j.jsv.2021.116217
• Languages: English
• ISSNs: 0022-460X

Abstract

Highlights: Investigation of vibration attenuation in a finite array of symmetric/asymmetric periodic rods. Analytical expressions derived to predict the behaviour of N periodic cells. Determination of simple expressions to estimate the attenuation band and the minimum transmissibility within this band. Demonstration that a correctly orientated finite array of asymmetric cells outperforms the a comparable array of symmetric cells in terms of both bandwidth and minimum transmissibility. Theoretical analysis is supported with experimental results. Abstract: Periodic structures have an important role to play in the reduction of vibration within a targeted frequency range. Much of the literature concerning vibrations in periodic structures involves the description of wave behaviour in infinite structures. This paper concerns the dynamic behaviour of a finite mono-coupled periodic structure, concentrating on the prediction of the vibration transmission through the complete structure in terms of the displacement transmissibility of a single cell. An investigation is conducted into the effects of either using an array of symmetric or asymmetric cells comprised of rods, on the lowest frequency range targeted for vibration attenuation. The importance of the orientation of asymmetric cells with respect to the source is also discussed. Analysis of the systems shows that correctly orientated asymmetric cells offer better performance than an array of symmetric cells for a finite mono-coupled periodic structure. Provided that the periodic structure is not connected to a structure that significantly affects its dynamics, there is improved performance both in terms of a wider frequency range in which there is vibration attenuation, and the maximum vibration attenuation within this frequency range. Analytical expressions are derived that allow the prediction of the maximum attenuation within the attenuation band based on the number of symmetric or asymmetric cells. Some experimental work is also presented to support the theoretical predictions.