Use of Non-Degeneracy in Nominally Axisymmetric Structures for Fault Detection With Application to Cylindrical Geometries

Royston, Thomas J.; Spohnholtz, Todd; Ellingson, W. A.

doi:10.1006/jsvi.1999.2653

Cited by 15 publications

(14 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…They derived an expression for the damage index that requires only the radial component of shell vibration. Royston et al (2000) proposed a flaw detection method by using the slit-mode phenomena that may occur when the degenerate vibratory modes of the axisymmetric structure become non-generate due to the flaws. Ip and Tse (2002) presented a feasibility study on locating damage in circular cylindrical fiber-reinforced composite shells based on the frequency sensitivities and mode shape information at specific locations.…”

Section: Introductionmentioning

confidence: 99%

“…The SDIMs for cylindrical shells have been introduced by some researchers (e.g., Srinivasan and Kot, 1998;Royston et al, 2000;Ip and Tse, 2002;Kim et al, 2004). Srinivasan and Kot (1998) proposed to use a damage index method for locating damage in circular cylindrical shells, which is basically based on the damage-induced change in the modal strain energy.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Identification of multiple directional damages in a thin cylindrical shell

Lee

Kim

2006

International Journal of Solids and Structures

View full text Add to dashboard Cite

In this paper, a structural damage identification method (SDIM) is developed to identify the line crack-like directional damages generated within a cylindrical shell. First, the equations of motion for a damaged cylindrical shell are derived. Based on a theory of continuum damage mechanics, a small material volume containing a directional damage is represented by the effective orthotropic elastic stiffness, which is dependent of the size and the orientation of the damage with respect to the global coordinates. The present SDIM is then derived from the frequency response function (FRF) directly solved from the equations of motion of a damaged shell. In contrast with most existing SDIMs which require the modal parameters measured in both intact and damaged states, the present SDIM may require only the FRF-data measured at damaged state. By virtue of utilizing FRF-data, one may choose as many sets of excitation frequency and FRF measurement point as needed to acquire a sufficient number of equations for damage identification analysis. The numerically simulated damage identification tests are conducted to study the feasibility of the present SDIM.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Identification of multiple directional damages in a thin cylindrical shell

Lee

Kim

2006

International Journal of Solids and Structures

View full text Add to dashboard Cite

show abstract

“…Furthermore, it is simplified as a circular ring because the fundamental vibration mode of a cylindrical shell is the ring like mode. The governing equations (Royston et al, 2000;Werner, 2005) are written as: Then, the two groups, radial and circumferential of natural frequencies (Royston et al, 2000;Soedel, 2005) can be derived as follows:…”

Section: Simplified Model and Theorymentioning

confidence: 99%

“…However, if the cylindrical shell is not axisymmetric, the split mode phenomenon happens. That is, the two modes in one pair which initially have identical natural frequencies split and the two identical frequencies become slightly different (Royston et al, 2000). Therefore, when the ±nth natural frequencies are obtained, the wall thickness can be evaluated according to Eq.…”

Section: Simplified Model and Theorymentioning

confidence: 99%

See 1 more Smart Citation

Vibration based damage assessment of type 1 compressed natural gas cylinder

Zhang¹

View full text Add to dashboard Cite

China, for his numerous suggestions and constructive remarks. The author would also like to express his sincere gratitude to other research team members for providing numerous suggestions and sharing their findings and experience. Many thanks also to the technicians in Protective Engineering Laboratory and Construction Technology Laboratory for their valuable assistance in the experimental work. The author is very grateful to the Land Transport Authority of Singapore for kindly funding this project and Maritime Research Centre in the School of Civil & Environmental Engineering, Nanyang Technological University, Singapore, for providing his opportunity to conduct the research. Thanks are also given to my colleague Wang longqi for his outstanding technical support. Most importantly, I would like to thank my parents and wife for their understanding, unconditional love and encouragement. Without their constant spiritual support, the successful completion of this project would be impossible.

show abstract

Condition Monitoring with Incomplete Information

Marwala

2011

Condition Monitoring Using Computational Intelligence Methods

View full text Add to dashboard Cite

Use of Non-Degeneracy in Nominally Axisymmetric Structures for Fault Detection With Application to Cylindrical Geometries

Cited by 15 publications

References 6 publications

Identification of multiple directional damages in a thin cylindrical shell

Identification of multiple directional damages in a thin cylindrical shell

Vibration based damage assessment of type 1 compressed natural gas cylinder

Condition Monitoring with Incomplete Information

Contact Info

Product

Resources

About