Session: Virtual Presentations in Acoustics, Vibration, and Phononics

Paper Number: 95206

95206 - Design and Numerical Analysis of Locally-Resonant Meta-Lattice Structure for Vibration Attenuation 

Meta-materials are artificial materials that perform superior properties in addition to natural behavior. Regardless of their chemical properties, metamaterials show high performance due to their geometric orientation. These designs are often used to manipulate wave propagation; In this context, electromagnetic, optical, and mechanical metamaterials exist. Mechanical metamaterials are used in vibration and acoustic fields, the main subject of which is wave transmission. The propagation of mechanical waves, which can cause problems such as structural damage, fatigue, poor performance, and discomfort in the industry, can be prevented or reduced by using meta-materials. Mechanical waves of various frequencies can be reduced or eliminated by locally resonant metamaterials obtained by adding various masses to viscoelastic materials. As a new generation design, polymer metamaterials are low-cost products and are candidates for use in various application areas such as aviation, automotive, white goods, and manufacturing machines due to their hollow structure and lightweight properties. Metamaterials can be designed by modifying various lattice structures. With the literature survey, higher performance metamaterials will be designed by modifying the lattice structures that are currently used for vibration isolation. Metamaterials that are used in vibration attenuation, create bandgaps depending on the design parameters. Theoretically, no wave transmission is observed at bandgap frequencies. In this context, metamaterials can be applied in situations where the operating frequency causes high amplitude vibration (resonance) by optimizing the bandgap determining parameters. Since low-frequency mechanical waves such as low-speed fan systems or shafts, and low-frequency sound waves are more difficult to isolate, metamaterials differ from traditional vibration isolation methods by considering the adjustable bandgap. Meta-lattice structures can be manufactured with additive manufacturing due to their complex geometries. The fact that the material consumption in the parts produced by additive manufacturing is very minimal compared to the conventional production techniques and the materials to be used in the design are suitable for recycling, show that meta-material designs are environmentally and ecologically friendly. The vibration suppression performance and bandgap creation are investigated theoretically, numerically, and experimentally methods. For numerical analysis, a bandgap formation will be determined for the unit cell using the Bloch-Floquet Theorem. When designing the unit cell, it is needed to remark the periodicity. The Bloch-Floquet Theorem implies that if a unit cell has bandgap(s) under its eigenfrequencies, the final lattice structure which is formed by this unit cell will certainly have bandgap(s). To design a lattice-based structure, it is needed to design a unit cell that gives bandgap(s) within its eigenfrequency at first. Besides, it can be confirmed that the final lattice structure will have bandgap(s) if the unit cell which forms the structure has bandgap(s). In both cases, it is more sensible to design and analyze the unit cell beforehand. After the determination of unit cell, the structure will be analyzed with analytical and modal finite element methods. The validation will be ensured by using experimental data. In the designing process, manufacturability will be an important criterion. Stereography (SLA) or filament fused fabrication (FFF) manufacturing techniques will be used according to the requirements of the design. Impact hammer and shaker tests will be applied to the manufactured structure. The analytical and numeric results will be compared and validated to the experimental data.

Presenting Author: Utku Güngör TOBB University Of Technology And Economics

Presenting Author Biography: I am, Utku Güngör, a senior mechanical engineering student at TOBB University of Economics and Technology. My main area of interest is acoustics & vibration. I worked in the system dynamics and control laboratory as an undergraduate researcher. Me and my colleagues are currently studying our senior design project. I am also interested in the philosophy of art and aesthetics. I am planning an academic career in my area of interest.

Authors:

Utku Güngör TOBB University Of Technology And Economics
Ahmet Arda Kurt TOBB University of Economics and Technology
Mert Lale TOBB University of Economics and Technology
Furkan Acar TOBB University of Economics and Technology
Recep Muhammet Görgülüarslan TOBB University of Economics and Technology
Hakkı Özgür Ünver TOBB University of Economics and Technology