09:45 〜 10:00
▲ [16a-421-4] Effects of Viscosity on Laser-Induced Cavitation Bubble Studied by High-Speed Laser Stroboscopic Videography
キーワード：Cavitation, Bubble dynamics, viscosity
Experimental investigations on the effects of liquid viscosity on laser-induced bubble dynamics have been carried out by high-speed laser stroboscopic videography technique. We used pure water and silicon oil with wide range of kinetic viscosities and laser pulse energy with range of 10 to 50 mJ. The dynamics of cavitation bubble is observed at intervals as short as 1 µs. A 10 ns laser pulse of designated pulse energy was focused in liquid filled in rectangular cell. A laser-induced bubble was formed at the focus, grew to reach maximum size, shrank to collapse and then the second bubble grew again.The experimental results show that cavitaton behavior is obviously affected by liquid viscosity. The lifetime and the maximum size of bubble decreased and the bubble became ellipsoidal shape along irradiation direction with increase in the kinetic viscosity of liquid.