Simulative And Experimental Research On Structural Vibration Control Of Piezoelectricity Intelligent Beam

Intelligent structure possesses various preferable properties in dynamic circumstances and online use, such as self-test, self-diagnosis, self-monitoring, self-repair and self-adaptation. In recent years, the research on intelligent structure arouses worldwide attention, especially of those major developed countries. The vibration control, a branch of intelligent structure's application, has been widely adopted in the areas of military, machinery, medicine, and civil products, especially in aerospace industry, where its great potential has been already shown.In the beginning of this thesis, types and characteristics of intelligent material elements have been introduced. And the basic equations of piezoelectric material have been given. Then according to Hamilton principle, both the static and dynamic finite element equations for the intelligent structure are formulated with isoparametric element of bending plate or bending beam. For the general structure with complicated configuration and boundary condition, three-dimensional finite element equations are deduced.By constructing a simplified model of the beam in computer, every mode of vibration has been analyzed through finite element method on ANSYS platform. Both transient analysis and dynamic analysis have been carried out by properly converting the real loads to the equivalent ones, which are comparatively easy to manipulate for the software. The optimum layout of actuators, on which the best effect of vibration reduction may be provided to each mode, has been gotten. After hard work of numerical simulation, the conclusion is achieved that the voltage that is applied on the piezoelectric material should keep the same phase of the load of forced vibration.Finally, the vibration experiment of intelligent beam has done with pieces of piezoelectric material chips being adhered to a base beam of section-constant cantilever. The working principle of the experiment, the composition of the experiment, the power supply of the actuators, and the control method of the whole system are designed and constructed. The result of the experiment and the result of numerical simulation are consistent with each other appreciably.A systematic and though elementary research on vibration reduction technology of intelligent beam is conducted in this paper. The research proves that the finite element method is a simple and practicable approach to the analysis of structural problems by employing appropriate models and configurations.