International Journal of Fluid Mechanics Research

ISSN for PRINT: 1064-2277

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2005, Volume32

Issue 5

124 pages

DOI: 10.1615/InterJFluidMechRes.v32.i5

Issue price - $270.00

I. V. Vovk
Institute of Hydromechanics of National Academy of Sciences of Ukraine, Kyiv, Ukraine

V. T. Matsypura
National Engineering University of Ukraine "KPI", Kyiv, Ukraine

A problem on sound radiation by an array consisting of piezoceramic shells with the end baffles in the form of truncated spherical sectors is solved on the basis of the modified method of partial domains. The significant distinctions between the vibration velocities and radiated powers of the particular shells is shown in the case when all of them are excited by equal electric voltages, that is caused by interaction through the acoustic field. It is proved that at certain frequencies some shells may change their operation mode from power radiation to its absorption from the environment. The far field of sound radiation by the shell is studied and directivity patterns for the arrays with various properties of the surface baffles are calculated. It is found that the most effective baffles are those with completely soft surfaces. A problem on sound radiation by the array which shells are excited by periodic sequence of radio-pulses. It is shown that in the case when all the shells are supplied by equal radio-pulses time dependencies for the vibration velocities of the shells (within radio-pulse duration interval) essentially differ both from the exciting pulse and from each other. It is found that at pulse supply of the shells the pressure time evolution in the far field significantly depends on direction. The pronounced acoustic reverberation is discovered in pulse-to-pulse interval. Some specific techniques for controlling the array acoustic properties are considered.

DOI: 10.1615/InterJFluidMechRes.v32.i5.70 Download article, 588-633 pages

Article price - $100.00

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