Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Topology optimization of elastic internal resonators for sandwich metastructures
Submission Author:
Carlos Andrés Rincón Velásquez , SP , Brazil
Co-Authors:
Carlos Andrés Rincón Velásquez, Marcelo A. Trindade
Presenter: Carlos Andrés Rincón Velásquez
doi://10.26678/ABCM.COBEM2023.COB2023-0799
Abstract
Metastructures have gained attention in recent years due to their noise and vibration isolation properties in tunable frequency ranges, basing their behaviour on the principle of phononic crystals. These phononic crystals exhibit frequency ranges known as bandgaps, in which elastic and acoustic waves do not propagate. Metastructures are achieved from the addition of resonator elements, which act as vibration absorbers and are periodically distributed in host structures. The advantage of applying metastructures is that, unlike phononic crystals, the bandgaps are generated based on the properties of the resonator elements, this paves the way towards compact and lightweight vibroacoustic solutions for the lower frequency ranges, since that the waves can be affected by the incorporation of resonator elements of sizes smaller than the wavelength. An approach in the investigation of metastructures is the search for optimal geometry of resonators, which can provide a reduction of vibrations in a greater range of frequencies, or allow the damping of relatively distant resonance peaks. That is why this research work proposes a topological optimization to find the geometry of an elastic resonator, as a building block of a sandwich type metastructure. In the development, the topology optimization based on a modified method of penalization, together with the objective function and the constrains, which show the sensitivity of the resonator with respect to its properties and its coupling with the host structure, are implemented in a modeling tool based on finite elements that uses uniform isoparametric hexahedron elements with two degrees of freedom in each node, and also was developed in this research work. Numerical results show that the proposed modified method with penalization and the objective functions generate an efficient resonator geometry, with relative density values between zero and one for each of the isoparametric elements of the discretization.
Keywords
Topology optimization, Metastructure, Control of vibrations
