ABOUT FREE INTERFACIAL VIBRATIONS OF THIN ELASTIC CIRCULAR CYLINDRICAL SHELLS

Ghulghazaryan G.R., Doctor of Physical and Mathematical Sciences, Professor of the Department of Mathematical Analysis and Theory of Functions, Armenian State Pedagogical University after Khachatur Abovian, Yerevan, Armenia
Ghulghazaryan L.G., Candidate of Physical and Mathematical Sciences, Senior Researcher, Officer of the Institute of Mechanics of the NAS of Armenia, Associate Professor of the Department of Mathematical Analysis and Theory of Functions, Armenian State Pedagogical University after Khachatur Abovian, Yerevan, Armenia

Free interfacial vibrations of closed and non-closed infinite cylindrical shells composed of two semi-infinite orthotropic thin cylindrical shells with different elastic properties are studied. Using the system of equations of the related classical theory of orthotropic cylindrical shells, dispersion equations and asymptotic formulas for obtaining eigenfrequencies of possible interfacial vibrations of composed cylindrical shells are derived. An algorithm for separating possible interfacial vibrations is presented. An asymptotic link is established between the dispersion equations of problems in hand and analogous problems for infinite composed plate and plate-strip, respectively. By examples of shells with different radiuses approximate values of dimensionless characteristics of eigenfrequencies and attenuating characteristics of the related vibration forms are given.

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