THE EFFECTS OF SURFACTANT ADDITIVES ON THE ACOUSTIC AND LIGHT EMISSIONS FROM A SINGLE STABLE SONOLUMINESCING BUBBLE

The localized concentration of energy during a single bubble collapse is manifested in two forms, which are the emission of an acoustic puls e, and the emission of a light pulse. Through precise control of exper imental parameters, one can levitate a single bubble in a standing wav e field and measure the magnitude of the acoustic and light pulses res ulting from the violent collapse of the cavity. The information acquir ed from such measurements provides better understanding of the mechani sms that are responsible for the emissions, which may lead to the prac tical application of controlled bubble implosions. An experimental app aratus was developed to measure the acoustic and light emissions from a single, stable sonoluminescing bubble. Two surfactant additives were studied to determine the effects on the bubble emissions, Triton X-10 0, which has previously been shown to provide free interfacial motion, reduced tile magnitude of both the acoustic and light pulses from the bubble. The protein bovine serum albumin (BSA) which has been shown t o hinder interfacial motion, allowed the bubble to be driven to higher acoustic pressures, and resulted in an increase in the magnitude of t he light pulses from the bubble. Images of the sonoluminescing bubble indicate Chat the collapse remains spherical in the cases presented, a nd that bubble translation can be correlated with weak acoustic and li ght emissions. (C) 1997 Acoustical Society of America.