Thermal cavitation mechanism for generation of underwater sound

• Autorzy: Buogo S. , Cannelli G. B.
• Konferencja: Proceedings of the 2 nd EAA International Symposium on Hydroacoustics 24-27 May 1999, Gdańsk-Jurata POLAND
• Języki publikacji: EN

Abstrakty

EN

The implosion of a vapour bubble generated by spark discharges in seawater can generate high power pulses in the frequency band up to a few hundred kHz, useful to obtain high-resolution imaging of the sea subboftom. In this paper, a physical model is illustrated to explain the origin of the process generating the bubble in a conducting liquid, together with a brief review of the hypofhized ideas on the growth and implosion mechanism of the bubble. A description is given of the implementation of a numerical scheme for the solution of a set of equations describing the temperature and electric field distributions in the liquid in the prebreakdown stage. According to this model, electrical breakdown and subsequent thermal cavitation in seawater is governed by Joule heating with a temperature dependent electrical conductivity. Measurements of the discharge of the paraboloidal sparker-based source confirm the validity of the energy model, showing a good agreement of the predicted time required for liquid vaporization with the observed breakdown time.

• Wydawca: Polskie Towarzystwo Akustyczne. Oddział Gdański
• Czasopismo: Hydroacoustics
• Rocznik: 1999
• Tom: Vol. 2
• Strony: 207--212
• Opis fizyczny: Bibliogr. 16 poz., rys.

Twórcy

autor

Buogo S.

• CNR - Istituto di Acustica "o. M. Corbino" Underwater Acoustics Laboratory Via deI Fosso del Cavaliere 100,00133 Roma, ltaly

autor

Cannelli G. B.

• CNR - Istituto di Acustica "o. M. Corbino" Underwater Acoustics Laboratory Via deI Fosso del Cavaliere 100,00133 Roma, ltaly

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