Dynamics of sonoluminescing bubbles within a liquid hammer device

RAÚL URTEAGA; PABLO GARCÍA MARTINEZ; FABIÁN J. BONETTO

PHYSICAL REVIEW E

AMER PHYSICAL SOC

Año: 2009 vol. 79 p. 163061 - 163068

1539-3755

We studied the dynamics of a single sonoluminescing bubble
SBSL in a liquid hammer device. Inparticular, we investigated the phosphoric acid–xenon system, in which pulses up to four orders ofmagnitude brighter than SBSL in water systems
about 1012 photons per pulse have been previously reportedChakravarty et al., Phys. Rev. E 69, 066317
2004. We used stroboscopic photography and a Mie scatteringtechnique in order to measure the radius evolution of the bubbles. Under adequate conditions we may positiona bubble at the bottom of the tube
cavity and a second bubble trapped at the middle of the tube
upperbubble. During its collapse, the cavity produces the compression of the liquid column. This compressiondrives impulsively the dynamics of the upper bubble. Our measurements reveal that the observed light emissionsproduced by the upper bubble are generated at its second collapse. We employed a simple numericalmodel to investigate the conditions that occur during the upper bubble collapse. We found good agreementbetween numerical and experimental values for the light intensity
fluence and light pulse widths. Resultsfrom the model show that the light emission is increased mainly due to an increase in noble gas ambient radiusand not because the maximum temperature increases. Even for the brightest pulses obtained
2
1013 photons,about 20 W of peak power the maximum temperatures computed for the upper bubble are always lower than20 000 K.