Dynamics and radiation of single cavity in an abnormal compressible bubbly media

Abstract

The equation of a pulsation of a single cavity in the equilibrium (on pressure) bubbly medium was suggested. The state of such medium is described by Lyakhov's equation which at the condition of pressure equilibrium in the both phases (gas/liquid) becomes essentially simpler. The numerical analysis of features of cavity dynamics and the acoustic losses was executed. The notion "acoustic losses" mean a radiation generated by cavity. The analysis of radiation parameters was restricted by the vicinity of cavity wall from a liquid side. The studies of cavity behavior, the structure and amplitude of a radiation have shown that the degree of a cavity compression by a stationary shock wave goes down when the volumetric concentration of gas phase K in the medium increases. The amplitude of pulsation essentially decrease and function R(t) (radius cavity vs. time) asymptotically (without oscillations) tends to the equilibrium state when K is equal approximately 3%. The equilibrium state is defined by amplitude of an incident shock wave and does not depend on K-value. The structure of a radiation wave takes the "soliton" form, its amplitude is essentially lesser and the width is much more in the comparison with corresponding parameters for a single-phase liquid. (RFBR 06-01-00317a financial support).