Investigation of novel geometrical design concepts for damping treatments

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2022-11

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Çavuş, Bertuğhan

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Surface damping treatment concepts are developed utilizing viscoelastic materials as a damping layer where it is applied to the main structure. The main aim for adding these materials is to increase cyclic deformation in the frequency region of interest, which increases dissipated energy from the main structure. Constrained layer damping treatment is the most common, where the viscoelastic layer is constrained by a stiff top layer. Recently, a spacer or standoff layer has been added between the base and constrained damping layer to increase the damping performance of the structure. Adding a standoff layer increases the distance between the damping layer and the base layer, which results in increasing shear strain. Also, the electromagnetic and acoustic metamaterial concepts are extended to reduce vibration levels using the vibration absorber analogy, known as mechanical metamaterial or metastructure concept. It is developed by embedding vibration absorbers to the main structure rather than attaching them in this concept. In the frame of this thesis study, novel damping treatment designs are developed using surface damping treatment and vibration absorber concepts to optimize dynamic behavior and reduce vibration amplitudes of the main structure. The proposed designs are compared using the performance metric that quantifies the vibration damping performance of the design. Hence, the main aim is to find optimal design geometry that maximizes vibration amplitude reduction with minimum mass. The modelling of these complex geometries is developed in ANSYS finite element simulation environment. Finally, the proposed optimum designs are manufactured and tested to verify the methodology used and finite element results.

Subject Keywords

Passive standoff layer damping treatment, Metastructures, Structural optimization, Vibration absorbers, Passive vibration control techniques, Standoff layer

URI

https://hdl.handle.net/11511/101217

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Çavuş, “Investigation of novel geometrical design concepts for damping treatments,” M.S. - Master of Science, Middle East Technical University, 2022.