Title: Surface bubble lifetime in the presence of a turbulent air flow, and the effect of surface layer renewal Show Chinese title

Title: 表面气泡在湍流空气流中的寿命，以及表面层更新的影响

Abstract: Surface bubbles in the ocean are critical in moderating several fluxes between the atmosphere and the ocean. In this paper, we experimentally investigate the drainage and lifetime of surface bubbles in solutions containing surfactants and salts, subjected to turbulence in the air surrounding them modelling the wind above the ocean. We carefully construct a setup allowing us to repeatably measure the mean lifetime of a series of surface bubbles, while varying the solution and the wind speed or humidity of the air. To that end, we show that renewing the surface layer is critical to avoid a change of the physical properties of the interface. We show that the drainage of the bubbles is well modelled by taking into account the outwards viscous flow and convective evaporation. The mean lifetime of surface bubbles in solutions containing no salt is controlled by evaporation and independent on surfactant concentration. When salt is added, the same scaling is valid only at high surfactant concentrations. At low concentrations, the lifetime is always smaller and independent of wind speed, owing to the presence of impurities triggering a thick bursting event. When the mean lifetime is controlled by evaporation, the probability density of lifetime is very narrow around its mean, while when impurities are present, a broad distribution is observed. Show Chinese abstract

Abstract: 海洋中的表面气泡在调节大气和海洋之间的多种通量中起着关键作用。 在本文中，我们通过实验研究了含有表面活性剂和盐的溶液中的表面气泡的排水和寿命，在周围空气湍流条件下进行，模拟海洋上的风。 我们精心构建了一个装置，使我们能够重复测量一系列表面气泡的平均寿命，同时改变溶液和空气的风速或湿度。 为此，我们表明，更新表面层对于避免界面物理性质的变化至关重要。 我们表明，气泡的排水可以通过考虑向外的粘性流动和对流蒸发来很好地建模。 不含盐的溶液中表面气泡的平均寿命由蒸发控制，并且与表面活性剂浓度无关。 当加入盐时，同一标度仅在高表面活性剂浓度下有效。 在低浓度下，寿命总是更短，并且与风速无关，这是由于杂质的存在引发了一次厚厚的破裂事件。 当平均寿命由蒸发控制时，寿命的概率密度围绕其均值非常狭窄，而当存在杂质时，观察到一个宽分布。