Yu.A.Vengrenyuk, I.F.Kirichok, N.I.Obizyuk Resonant vibration and dissipative heating of piezoelectric shperical shells with account of phenomenon of heat depolarization |
Acoustic bulletin, Vol. 2 ¹ 2, (1999) |
| There is considered an axisymmetric problem on resonant vibration and dissipative heating of truncated spherical shell. The shell is composed from two rigidly fastened piezoceramic layers with equal thickness and opposite directions of thickness' polarization. A nonlinear problem is solved within the scope of electrothermomechanical theory of shells based on Kirchhoff-Love theory for mechanical variables and adequate assumptions for electric and temperature fields. Viscoelastic behaviour of piezoceramics is modelled by a concept of complex characteristics depending on the temperature of heating. A phenomenon of thermal depolarization is considered. By numerical analysis there has been investigated an influence of thermomechanical coupling, conditions of heat exchange, geometry and thermal depolarization on the temperatre-frequency and dynamical characteristics of spherical piezoelements at harmonic vibration. It has been shown that account of the temperature dependence of characteristics of the material gives rise to of the additional high-temperature branch in the non-linear temperatre-frequency characteristics and refines the value of electric load, beginning from which the appearance of depolarized zone in the element becomes possible. |
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KEY WORDS: piezoelectric shell resonance vibrations, dissipative heating, thermal depolarization, heat exchange |
| TEXT LANGUAGE: Russian |