I.V.Vovk, V.T.Matsipura Radiation of sound by the grating formed by coaxial cylindric piezoceramic shells with the end screens. Part II. Analysis of numerical results: the near field and the radiation power |
Acoustic bulletin, Vol. 4 š 4, (2001) |
| Acoustic properties of the grating, consisting of coaxial piezoceramic shells with the end screens in form of the soft truncated spherical cones, are investigated. It is shown, that under the identical electric excitation of all the shells the essential distinctions in shells' vibrational velocities and powers radiated by them are observed, that is conditioned by interaction through the acoustic field. Mentioned distinctions are especially considerable in the frequency domain near the eigenfrequencies of shells' pulsations. It is established that on definite frequencies some shells can shift from the energy radiation mode to its absorption from the surrounding medium. It is shown that in the cases, when the inside grating's volume is filled by a liquid, the resonance of this volume arises at relatively low frequencies. This resonance conditions an essential (more, than on order) rise of power radiated by the grating. It is shown that one can easily control the total power efficiency of the grating in low-frequency domain, varying the number of shells in grating. |
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KEY WORDS: the radiating grating, piezoņeramic shell, screen, far field, acoustic interaction |
| TEXT LANGUAGE: Russian |