Thermally tunable band gaps in architected metamaterial structures

The combined characteristics of periodicity and locally resonant features in metamaterial structures, or meta-structures, give rise to unique wave propagation characteristics such as relatively low and wide band gaps. These meta-structures have a fixed geometry and thus a fixed behavior, however applications that require structural vibration mitigation such as spacecraft and automotive components have variable vibration mitigation requirements over a range of operation and external conditions. In this work, we propose a method to thermally tune the band gaps of composite meta-structures, which combine a periodic lattice and locally-resonant inclusions, through changes in temperature of the structure. The concept primarily takes advantage of the different moduli of the two materials in the meta-structure that have drastically different temperature dependences, to preferentially tune the modulus of the lattice material compared to the resonant inclusion. We introduce an additional concept, termed thermal partitioning, to partially or fully open and close band gaps by locally controlling the temperature within the meta-structure. We demonstrate these results numerically with finite element simulations.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2018

Author dc:creator

• Nimmagadda, Chaitanya

Contributors dc:contributor

• Matlack, Kathryn H

• Phononic crystals
• metamaterials
• tunable band gaps
• architected materials
• vibration mitigation

Statement dc:rights

• Copyright 2018 Chaitanya Nimmagadda

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/101826

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/101826