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Scientific journal
Scientific Review. Technical science
ISSN 2500-0799
ПИ №ФС77-57440
ISSN 2500-0799
ПИ №ФС77-57440
PRACTICAL APPLICATION OF FINITE ELEMENT ANALYSIS IN THE TEACHING DISCIPLINE «FUNDAMENTALS OF VIBRATION OF STRUCTURES AND MACHINES»
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Definition of diagnostic features of occurrence and development of cracks in structures is one of the main tasks of vibration. Experimental determination of vibrodiagnostics characteristics associated with high material costs. For their definitions currently used calculation methods. In an article in the framework of the educational process on the example of a beam-wall is proposed and shown the possibility of using Gap-elements in finite element description of tasks vibrodiagnostics to reflect the dynamic process of “breathing” of the crack. With the passage of the harmonic signal via the line element, which is of elastic design does not have a crack, signal (response) should remain unchanged in shape, getting only a different amplitude and initial phase. This assertion is well supported when subjected to linear FE-model of elastic beam-wall in the absence of cracks of one and two harmonic forces at different combinations of frequencies. To create a nonlinear FE-model used Gap-elements located in the region of the crack. With the passage of the harmonic signal through a nonlinear element, which is of elastic design, with a crack in the spectrum of the signal (response) should receive the frequency combination . This statement is also proved when subjected to nonlinear FE-model one and two harmonic forces. According to the results of the numerical experiment graphs of some vibro parameters depending on the crack length, which will allow their use in the monitoring of structures during their operation.