Abstract
An analytical and experimental investigation was performed to determine the natural frequencies and mode shapes of a cone-cylinder segmented shell. The finite-element technique was used to predict the natural frequencies and mode shapes of a clamped segmented shell. In the experimental phase of the program, the shell was excited by an electromagnet and the natural frequencies were determined with the aid of a microphone. Holographic interferometry was used to identify the mode shapes for each resonant frequency. The analytical and experimental results were in good agreement with one another.
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Abbreviations
- a i :
-
coefficient of thei-th term in the assumed displacement field
- n :
-
number of circumferential waves
- m :
-
number of meridional half-waves
- q i :
-
i-th generalized coordinate
- \(\dot q_i\) :
-
velocity ofq i
- s :
-
shell meridional coordinate
- t :
-
time, sec
- T :
-
kinetic energy of the shell, in.-lb
- u :
-
meridional displacement of the shell, in.
- U :
-
strain energy of the shell, in.-lb
- v :
-
circumferential displacement of the shell, in.
- w :
-
normal displacement of the shell, in.
- W :
-
work of the conservative, external loading, in.-lb
- θ:
-
shell circumferential coordinate
- ϕ:
-
angle between axis of revolution and normal to shell, rad
- ω:
-
natural frequency, rad/sec
- ψ:
-
rotation of the middle surface
- [K]:
-
shell-stiffness matrix
- [M]:
-
shell-inertia matrix
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Lashkari, M., Weingarten, V.I. Vibrations of segmented shells. Experimental Mechanics 13, 120–125 (1973). https://doi.org/10.1007/BF02323969
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DOI: https://doi.org/10.1007/BF02323969