Modelagem numérico-computacional e avaliação experimental do autoaquecimento de materiais viscoelásticos

Detalhes bibliográficos
Ano de defesa: 2010
Autor(a) principal: Cazenove, Jean Antoine de
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Uberlândia
BR
Programa de Pós-graduação em Engenharia Mecânica
Engenharias
UFU
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: https://repositorio.ufu.br/handle/123456789/14874
Resumo: In the present work, a methodology for numerical simulation of self-heating phenomenon in viscoelastic materials has been developed, with the aim of proposing and validating finite element models that can be applied to predict the thermomechanical behaviour of structures including viscoelastic materials. The model takes into account the dependence of the mechanical characteristics of the viscoelastic material with respect to frequency and temperature and allows to obtain the transient temperature field. For this purpose, the heat source calculation is computed based on the dissipated energy obtained from the harmonic response calculation as the structure is submitted to cyclic loading. The validation of the model and the adjustment of two initially unknown parameters, namely the film coefficient for natural heat convection and the ratio of the heat source over the mechanical power dissipated through viscoelastic effects, were carried out by comparison of the model-predicted responses to experimental results counterparts, the latter being obtained by the application of a cyclic load to a sample specimen by means of a universal test machine, and measuring the temperatures within the viscoelastic material of the dispositive using thermocouples. A curve-fitting procedure was developed using an optimization routine, in order to identify optimal set of values of h and b. For each test, the experimental results were compared to those obtained from the numeric model after the identification, thus allowing the evaluation of the accuracy and limitations of the proposed model procedure.