The dynamics of hydrogen bubbles produced by water electrolysis in an acidic electrolyte are studied using electrochemical and optical methods. A defined cyclic modulation of the electric potential is applied at a microelectrode to produce pairs of interacting H$_2$ bubbles in a controlled manner. Three scenarios of interactions are identified and systematically studied. The most prominent one consists in a sudden reversal in the motion of the first detached bubble, its return to the electrode and finally its coalescence with the second bubble. Attested by Toepler's schlieren technique, an explanation of contactless motion reversal is provided by the competition between buoyancy and thermocapillary effects.
Three-dimensional numerical study on hydrogen bubble growth at electrode
Sorbonne Université（索邦大学）；CNRS, Institut Jean Le Rond d’Alembert UMR 7190（法国国家科学研究中心，让·勒朗·达朗贝尔研究所 UMR 7190）；State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University（西安交通大学航天学院，机械结构强度与振动国家重点实验室）
Alternative interpretation of the sign reversal of secondary Bjerknes force acting between two pulsating gas bubbles
已知在特定情况下，作为作用在脉动气泡之间的辐射力的次级Bjerknes力改变，例如，从吸引到排斥。本文对两个球形气泡的这种现象进行了理论讨论。本文基于对相互作用气泡跃迁频率的分析[M. Ida，Phys. Lett. A 297，210（2002）]提供了一种解释，与以前的解释不同（例如，Doinikov和Zavtrak [Phys.Fluids 7，1923（1995）]）。它示出，例如，反转时发生的一个气泡是较小的，另一个是大于共振尺寸是由于第二高的过渡频率的较小的气泡，这是不能使用传统的自然频率分析。
