Modelling of Anisotropic Viscoelastic Behaviour in Super-Pressure Balloons
نویسندگان
چکیده
Large balloon structures are made of thin anisotropic polymeric film that shows considerable time-dependent material behaviour. While the material has been fully characterised and a detailed time-dependent material description by means of a nonlinear viscoelastic Schapery material model is available, there is no suitable numerical implementation for finite element analysis. This paper presents an algorithm for nonlinear viscoelastic and anisotropic material behaviour. After an overview of the material model, a detailed description of the iterative algorithm is given including the full set of equations. The model is implemented by means of a user-defined subroutine in ABAQUS. For verification a set of cylindrical balloons is observed analytically and experimentally and the results are compared.
منابع مشابه
Implementation and Validation of Schapery-Rand Anisotropic Viscoelasticity Model for Super-Pressure Balloons
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