An investigation into wave propagation in hanging chains

Autor(es)

Cleante, V. G. ; Goncalves, P. J. P. ; Waters, T. ; Brennan, M. J. ; Carneiro, J. P., Jr. ; Rade, D. A.

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physics: Conference Series; v. 2647, p. 7-pg., 2024-01-01.

Resumo

The study introduced in this work is motivated by the prospect of using a hanging chain as an Acoustic Black Hole (ABH) for passive vibration control. An ABH is effectively a waveguide in which a wave slows progressively as it propagates away from the source enabling it to be extinguished with modest damping. The effect can be achieved by engineering inhomogeneity into a structure's geometry or material, the most common realisation being a beam of tapered thickness. This paper proposes an alternative realisation, that of a chain hanging under its own weight. Such a system has a wave speed that naturally decreases to zero, owing to its linear variation in tension, thus overcoming the challenges of constructing precisely shaped beams with vanishingly thin tips. The study of transverse vibration of hanging chains is a classical problem in structural dynamics. The motion of the chain can be described in terms of Bessel or Hankel functions, which are needed to account for the variation in tension along the chain. In this work, the hanging chain problem is revisited from a wave propagation perspective. An expression is derived for the amplitude of the waves in an infinite chain due a point excitation. From which, the spatial behaviour and the receptances of the waves are evaluated, revealing differing characteristics of upward and downward propagating waves. Some experimental results are presented to support the theoretical analysis. (AU)

• Processo FAPESP: 19/19335-9 - Modelagem, projeto e análise experimental de estruturas periódicas não lineares
• Beneficiário: Jean Paulo Carneiro Junior
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 22/11995-2 - Projetando Metamateriais Usando Não-linearidade Geométrica para formar uma super band de atenuação em Baixa Frequências
• Beneficiário: Vinícius Germanos Cleante
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 22/09543-6 - Estratégias para formar uma super banda de atenuação em uma metaestrutura de viga finita usando uma série de ressonadores
• Beneficiário: Jean Paulo Carneiro Junior
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto
• Processo FAPESP: 18/15894-0 - Projeto e otimização de estruturas periódicas para aprimoramento de desempenho vibroacústico
• Beneficiário: Carlos de Marqui Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático