A simulation model is presented for the creep process of the rotating disks under the radial pressure in the presence of body forces. The finite strain theory is applied. The material is described by the Norton-Bailey...A simulation model is presented for the creep process of the rotating disks under the radial pressure in the presence of body forces. The finite strain theory is applied. The material is described by the Norton-Bailey law generalized for true stresses and logarithmic strains. A mathematical model is formulated in the form of a set of four partial differential equations with respect to the radial coordinate and time. Necessary initial and boundary conditions are also given. To make the model complete, a numerical procedure is proposed. The given example shows the effectiveness of this procedure. The results show that the classical finite element method cannot be used here because both the geometry and the loading （body forces） change with the time in the creep process, and the finite elements need to be redefined at each time step.展开更多
Soft material is becoming increasingly important to many industries, which leads to the demand for a better understanding of its mechanical properties under large deformation. In this paper, a technique of integrating...Soft material is becoming increasingly important to many industries, which leads to the demand for a better understanding of its mechanical properties under large deformation. In this paper, a technique of integrating the digital moire method and embedded-grating approach is presented for investigating mechanical behaviors of a vulcanized silicone rubber in contact with a wedge-shaped indenter. Two distinct deformation sectors are observed from the experimental result. A simple way of computing strain is also presented by analysing grid deformation within the framework of geometrical nonlinearity. Three regions were observed from strain distribution along the horizontal direction： the contact region, the sink-in region and the far-field region. Moreover, the extent of the sticky region and that of the slippy region within the contact interface are distinguished, which can provide realistic data for theoretical modelling. Based on the finite deformation elasticity theory, the distribution of contact pressure and shear stress over the contact interface are derived for prediction of possible cracks.展开更多
文摘A simulation model is presented for the creep process of the rotating disks under the radial pressure in the presence of body forces. The finite strain theory is applied. The material is described by the Norton-Bailey law generalized for true stresses and logarithmic strains. A mathematical model is formulated in the form of a set of four partial differential equations with respect to the radial coordinate and time. Necessary initial and boundary conditions are also given. To make the model complete, a numerical procedure is proposed. The given example shows the effectiveness of this procedure. The results show that the classical finite element method cannot be used here because both the geometry and the loading （body forces） change with the time in the creep process, and the finite elements need to be redefined at each time step.
基金Project supported by the National Natural Science Foundation of China(Nos.11127202 and 11227202)
文摘Soft material is becoming increasingly important to many industries, which leads to the demand for a better understanding of its mechanical properties under large deformation. In this paper, a technique of integrating the digital moire method and embedded-grating approach is presented for investigating mechanical behaviors of a vulcanized silicone rubber in contact with a wedge-shaped indenter. Two distinct deformation sectors are observed from the experimental result. A simple way of computing strain is also presented by analysing grid deformation within the framework of geometrical nonlinearity. Three regions were observed from strain distribution along the horizontal direction： the contact region, the sink-in region and the far-field region. Moreover, the extent of the sticky region and that of the slippy region within the contact interface are distinguished, which can provide realistic data for theoretical modelling. Based on the finite deformation elasticity theory, the distribution of contact pressure and shear stress over the contact interface are derived for prediction of possible cracks.
