Structural Health Monitoring of Composite Overwrap Pressure Vessel

摘要

Composite Overwrap Pressure Vessel (COPV) has increasingly been used in many structural systems for automobile, aerospace, and aeronautical applications. The composite overwrap increases the pressure carrying capacity of the vessel without adding too much weight on the tank. The composite overwrap is typically in the form of laminates with multiple layers of uni-directional carbon fibers. This class of composite material is relatively new to the engineering communities and their material behaviors are not as well understood as traditional materials such as metals and metallic alloys. To ensure safe operation of the structural system consisting COPV, an on-line automatic structural health monitoring system is needed to constantly monitor the performance of the structure. Many structural health monitoring techniques have been proposed. Most of these techniques are based upon the global or local dynamic characteristics of the structure or the material. The structural health monitoring system identifies the changes in the global or local dynamic characteristics and issues warnings or trigger structural control system to bring the structural performance back to normal. This kind of hybrid sensing/control system can be achieved by using proper smart materials such as the piezoceramics. The paper presents experimental and numerical results of dynamic analysis of COPV and the results of temperature dependency tests on the performance of piezoelectric transducers for the structural health monitoring on composite laminates. On-going research using smart piezoelectric material to serve as the actuator and sensor for a structural health monitoring system for COPV are discussed in the paper.