Metamaterial design in the hyperelastic regime

The design of metamaterials relies on numerical simulations to both obtain the basic distribution of displacements, stresses and strains throughout the domain, and to find structures that handle the loads optimally. Linear elasticity theory is often employed for these simulations; however, this form...

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Detalhes bibliográficos
Autor: Creus Costa, Ton
Tipo de documento: dissertação
Data de publicação:2024
País:España
Recursos:Universitat Politècnica de Catalunya (UPC)
Repositório:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglês
OAI Identifier:oai:upcommons.upc.edu:2117/411651
Acesso em linha:https://hdl.handle.net/2117/411651
Access Level:Acceso aberto
Palavra-chave:Metamaterials--Design
Elasticity
Finite element method
Topology
Hyperelasticity
Neo-hookean
Nearly-incompressible
Metamaterials
Topology optimization
Metamaterials--Disseny
Elasticitat
Elements finits, Mètode dels
Topologia
Àrees temàtiques de la UPC::Enginyeria dels materials::Materials compostos
Descrição
Resumo:The design of metamaterials relies on numerical simulations to both obtain the basic distribution of displacements, stresses and strains throughout the domain, and to find structures that handle the loads optimally. Linear elasticity theory is often employed for these simulations; however, this formulation fails to capture large displacements, and the results obtained in highly deformed structures may not be as efficient as possible. In this present work, the goal is to solve hyperelastic problems using Neo-hookean materials, using a formulation geared towards the field of topology optimization for further later implementations. Hyperelasticity is posed as a minimization problem, which is discretized using the finite element method, and solved using a Newton-Raphson algorithm implemented in a MATLAB-based topology optimization toolbox. After showing that the formulation is consistent with the small displacements theory, four tests are carried out to validate the implementation. The results obtained are promising from a physical meaning perspective, but a lack of quadratic convergence in the Newton-Raphson algorithm suggests the presence of an error in the calculation of the tangent operator.