Modélisation par éléments finis du couplage thermo-élastique dans les structures vibrantes

Micro-accelerometers and micro-gyrometers are being developed in order to respond to the demand of accurate miniature inertial navigation systems. In the design of such accurate systems, which require a high quality factor, the dissipation mechanisms such as the thermoelastic damping have to be considered. In order to assess the thermoelastic influence on the behavior of vibrating structures, analytical models may be used for simple configurations under very restrictive assumptions. In order to investigate more complex structures, the finite element method may be used. An oscillating clamped-clamped beam is modelled using thermoelastic finite elements. The analytical and finite element analyses show that the thermoelastic coupling implies a natural frequency shift, an amplitude attenuation, a difference of phase between the thermal and mechanical degrees of freedom and influences the quality factor of the resonating system.