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dc.contributor.advisorGordis, Joshua H.
dc.contributor.authorBouwense, Matthew D.
dc.dateSep-17
dc.date.accessioned2017-11-07T23:38:56Z
dc.date.available2017-11-07T23:38:56Z
dc.date.issued2017-09
dc.identifier.urihttp://hdl.handle.net/10945/56104
dc.descriptionApproved for public release; distribution is unlimiteden_US
dc.description.abstractThe use of finite element modeling (FEM) in design has expanded as computers have become more capable. Despite these advancements, the construction of physical prototypes remains an essential aspect of design and testing. FEM limitations include the inability to accurately account for joints, damping, and geometric complexities. Due to the reality gap between a FEM and the prototype, there may be design deficiencies that cannot be identified until the prototype is tested. Using eigenvalue sensitivities, enhanced by artificial boundary conditions (ABC), the gap between simulation and reality can be closed via FEM updating. With an updated FEM, the same eigenvalue sensitivities can be utilized to detect damage in structural systems in use. Damage that produces differences in natural frequencies between the structure and its FEM can be related to the loss in flexural rigidity, as it is usually assumed that mass modeling is correct. This indicator allows adjustment of a FEM to match a prototype or to detect damage in a potentially compromised structure via comparison to an updated FEM. Based on simulation, a combination of multiple pin and spring ABCs is optimal for producing an ideal sensitivity matrix, and thus, ideal damage detection capability. However, in the experimental realm, the synthesis transformation used to apply ABCs to the measured frequency response functions can distort the frequency response function peaks, leading to error. A compromise of a single pin ABC permits both effective model updating and damage detection.en_US
dc.description.urihttp://archive.org/details/experimentalvali1094556104
dc.publisherMonterey, California: Naval Postgraduate Schoolen_US
dc.rightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. As such, it is in the public domain, and under the provisions of Title 17, United States Code, Section 105, it may not be copyrighted.en_US
dc.titleExperimental validation of model updating and damage detection via eigenvalue sensitivity methods with artificial boundary conditionsen_US
dc.typeThesisen_US
dc.contributor.secondreaderKwon, Young W.
dc.contributor.departmentMechanical and Aerospace Engineering (MAE)
dc.subject.authorfinite element modelen_US
dc.subject.authoreigenvalue sensitivityen_US
dc.subject.authorartificial boundary conditionen_US
dc.subject.authorfrequency response functionen_US
dc.subject.authornatural frequencyen_US
dc.subject.authormodel updateen_US
dc.subject.authordamage detectionen_US
dc.description.recognitionOutstanding Thesis
dc.description.serviceLieutenant, United States Navyen_US
etd.thesisdegree.nameMaster of Science in Mechanical Engineeringen_US
etd.thesisdegree.levelMastersen_US
etd.thesisdegree.disciplineMechanical Engineeringen_US
etd.thesisdegree.grantorNaval Postgraduate Schoolen_US


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