### Influence of the contact area and value of the linearly distributed and concentrated mass with a circular cylindrical shell on the frequency and modes of natural oscillations

Pages 64-74

Finite element method shows the influence of the joining area and the relative value of linearly distributed mass along the angular coordinate and concentrated mass on natural oscillations and forms of a closed, circular cylindrical shell. We defined the ranges of concentrated and linearly distributed mass, added to a shell. The variation of the concentrated mass contact area markedly affects the lower frequency of the "shell-mass" system, in this connection, reducing the area of the shell leads to a marked decrease of the lowest split natural frequencies. The greatest of split natural frequencies decreases markedly with the increasing of contact area. More complex (mixed) oscillation modes of the "shell-mass" are detected. Dependence of the geometric characteristics of the shell with a concentrated mass of the lower split natural frequencies lower tone of oscillations, thus, revealing the dependence of frequencies on the length of the sheath. Linear contact area variation of the added mass and the circular coordinate has little effect on the oscillation frequency of the "shell-mass" system.

DOI: 10.22227/1997-0935.2014.7.64-74

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