A study of the characteristics of a cylindrical resonator with a two-layer filler

The natural oscillations of two-layer cylindrical resonators are analyzed over a wide range of resonator parameters. It is found that these resonators are characterized by a noticeable increase in the Q-factor of certain types of oscillations. They are also characterized by simultaneous resonance of two types of oscillations having different Q-factors, inversion of the resonance frequency spectrum, and independence of the Q-factor on the fill factor over a wide range of fill-factor values. These findings are explained from an energy viewpoint.