Vibration and damping analysis of orthotropic cylindrical shells with electrorheological core layer

The vibration and damping characteristics analysis of the orthotropic cylindrical shells with an electrorheological (ER) layer and a constraining layer are studied and discussed in this paper. An analytical model is developed and the discrete finite element method is adopted to investigate the vibration and damping characteristics of the sandwich orthotropic cylindrical shell system. And, the rheological properties of the ER material can be changed and controlled by applying various electric fields. In this study, the effects of thickness of the ER layer, constraining layer, applied electric fields on the vibration and damping characteristics of the sandwich cylindrical shell system are also discussed and found to affect the stiffness of the system and change the vibration and damping characteristics. It is seen that the larger applied electric fields, thickness of the constraining layer, and parameter E˜1 have larger natural frequency and smaller modal loss factor, respectively. On the contrary, the smaller natural frequency and modal loss factor will be also obtained with the increments of the thickness of ER layer.