Papers by Keyword: Modal Flexibility Curvature Difference

Abstract: A method based on modal analysis is put forward to solve the problem of detecting the debond defects of solid rocket motor nozzle divergent section in service. The modal flexibility curvature difference is used to identify the debond defects. The locations and sizes of debond defects can be estimated accurately. The results of simulations indicate that the inspection speed and efficiency are much higher than those of ultrasonic method are. The method is easy to realize outfield detection. This method can be applied to identify the debond defects of the nozzle divergent section or multilayer composite structure. It provides theoretical guidance and methodological reference for debond defects detection of multilayer composite structure.

Abstract: A new method called Grey Relation Modal Flexibility Curvature Difference (GRMFCD)is proposed and applied to the numerical experiment and experimental research of a substructure. The results show the ability of GMFCD to locate the inflicted damage and qualitatively evaluate its severity for single and multiple scenarios, with only a few lower order modal parameters. The effectiveness and advantages of GMFCD as compared to the flexibility indicators, such as the change in flexibility, the curvature of the flexibility difference, are demonstrated.