固着液滴中的气泡破裂
Bubble bursting in a sessile droplet
AI总结：
研究固着液滴中气泡破裂，通过实验与数值分析，发现液滴曲率和限制增强能量聚焦，低粘度下产生细快射流，高粘度时特定拉普拉斯数下液滴被喷出，还揭示了界面曲率附加压力梯度的关键作用。
AI中文摘要：
我们通过实验和数值方法分析了固着液滴内气泡的破裂。实验表明，固着液滴曲率和限制作用会增强能量聚焦。在低粘度状态下，这种效应会产生更细、更快的沃辛顿射流。在高粘度状态下，当拉普拉斯数（基于粘滞毛细管速度的雷诺数）小于无限液体浴中气泡的阈值时，液滴会被喷出。数值模拟显示了固着液滴界面曲率产生的附加压力梯度的关键作用。该力驱使液体流向腔体底部，压缩并加速射流形成。在低粘度极限下，腔体底部在射流喷出前会变得更平滑。
英文摘要：
We analyzed experimentally and numerically the bursting of a bubble within a sessile droplet. Our experiments show that both sessile droplet curvature and confinement enhance the energy focusing. In the low-viscosity regime, this effect results in thinner, faster Worthington jets. In the high-viscosity regime, droplets are ejected for values of the Laplace number (the Reynolds number based on the visco-capillary velocity) smaller than the threshold for a bubble in an infinite liquid bath. This is probably the major result of the present work. Numerical simulations show the critical role of the additional pressure gradient arising from the curvature of the sessile droplet interface. The resulting force drives the liquid towards the bottom of the cavity, compressing it and accelerating jet formation. In the low-viscosity limit, the bottom of the cavity becomes smoother before jet ejection. This effect resembles the energy-focusing enhancement that occurs in an infinite liquid bath at the critical Laplace number, where short-wavelength waves are damped by viscosity.
