116 音響場中における2個の気泡の運動におよぼす粘性の影響(S33-3 マイクロ気泡・粒子,S33 マイクロ・ナノフルイディクス)  [in Japanese] 116 Viscous Effects on Dynamics of Two Interacting Bubbles in Acoustic Fields  [in Japanese]

Viscous drag effects on the translational motion of pulsating bubbles are studied experimentally. Not only the translation but the radial motion of a pair of bubbles are observed using high-speed photography. Experimental results for the translation are compared to the previous theoretical model derived by Takahira. This model takes into account the diffusion of vorticity from bubble surface, and is valid even for intermediate Reynolds number. Two asymptotic models, which are valid for both upper and lower Reynolds numbers, are also compared to clarify the viscous effects. It is revealed that the potential flow theory overestimates the viscous drag for bubbles having the maximum radial Reynolds number of 100. Moreover, the validity of Takahira's model is verified experimentally for bubbles having Reynolds number of O (10).