Topology optimization with pressure loads and finite deformation

Autor(es)

Moscatelli, Eduardo ; Goncalves, Juliano Fagundes ; Lino, Carlos Eduardo ; da Silva, Andre Luis Ferreira ; de Sa, Luis Fernando Nogueira ; Silva, Emilio Carlos Nelli

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES; v. 303, p. 15-pg., 2025-10-01.

Resumo

The trend of using soft materials to design robots, wearables, and other products that interact with humans is driving the development of new technologies and design methods. Among the technologies used are pneumatic actuation and elastomeric structures, which demands analysis tools capable of handling pressure loads and finite deformation. Thus, this work proposes a topology optimization formulation to design structures subjected to pressure loads and undergoing large deformations. The formulation is based on the idea of transmitting pressure loads from the boundaries of the domain to the structure by imposing a hydrostatic stress state to the non-solid phase. In previous works, this idea has been explored with linear constitutive models and small deformations. The novelty here is the extension of the same idea to nonlinear geometric and material behavior by modeling solid elements with a Neo-Hookean constitutive model. The instabilities associated with non-solid elements undergoing large deformation is alleviated by assigning a linear constitutive behavior to non-solid phase. This work also proposes a material model to interpolate Nanson's relation, improving the robustness of the pressure load non-linearity. This new material model interpolation eliminates the need to fix a solid region close to the pressure load surface, as done in previous studies. It is shown that the formulation also handles the distribution of solid, fluid, and void, i.e., non-solid material in hydrostatic and non-hydrostatic states simultaneously. The structural analysis is solved with a Newton's method based on the secant search, and the optimization problem is solved with the Method of Moving Asymptotes. The internally-pressurized lid and the piston head benchmarks are investigated to assess the performance of the proposed formulation. It is seen that the optimization results change with the increase of the pressure for the benchmark problems, showing the importance of considering an appropriate constitutive behavior for large deformations. (AU)

• Processo FAPESP: 23/17518-4 - Método de otimização topológica aplicado ao projeto de células a combustível de óxido sólido
• Beneficiário: Juliano Fagundes Gonçalves
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 14/50279-4 - Brasil Research Centre for Gas Innovation
• Beneficiário: Julio Romano Meneghini
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa Aplicada
• Processo FAPESP: 20/15230-5 - Centro de Pesquisa e Inovação de Gases de Efeito Estufa - RCG2I
• Beneficiário: Julio Romano Meneghini
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa Aplicada
• Processo FAPESP: 21/02340-0 - Otimização topológica de selos labirintos considerando escoamento turbulento e interação fluido-estrutura com variáveis binárias
• Beneficiário: Eduardo Moscatelli de Souza
• Modalidade de apoio: Bolsas no Brasil - Doutorado