Faithin Omaha eBook Collection

Download or read book Investigation of Coupled Analysis Techniques for Adaptive Material Structural Systems written by and published by . This book was released on 1992 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research program is to investigate coupled analysis techniques for adaptive material structural systems. There are two aspects of this research: one is to develop a nonlinear full-field constitutive model for ferroelectric materials, including piezoelectric and electrostrictive materials; the other is to develop an impedance-based analysis technique for adaptive material systems. A coupled electro-thermal-mechanical nonlinear constitutive relation for piezoelectric materials has been developed and verified based on experimental data from the literature. This model uses the polarization fraction as a newly established internal variable. This internal variable is related to other parameters such as electric field, stress, frequency, etc., using a hyperbolic tangent function, which accurately describes the nonlinearity, including the hysteresis of ferroelectric materials. The same approach has also been utilized in the modeling of relaxor ferroelectric PMN-PT materials. An impedance methodology for the dynamic analysis of adaptive material systems has been developed. This approach can provide accurate theoretical prediction of the dynamic response of a structure driven by any type of actuator and yet reflect the physical essence of the actuator/structure interaction. This model has been experimentally verified.