AI 中文总结
研究微米级气泡破裂产生的沃辛顿射流，通过理论和数值模拟得出射流基部半径与时间关系及局部韦伯数特性，模拟中界面坍塌成通用形状，还预测了水的纳米级海喷雾气溶胶初始半径。
AI 中文摘要
当微米级气泡破裂时，毛细波将腔体变形为一个锥体，从而喷射出沃辛顿射流。该射流由惯性聚焦产生，局部坍塌遵循由半角β设定的自相似欧拉解。用无量纲射流基部半径$r_j$和速度$v_j$表示，局部韦伯数$We_j = r_j v_j^2$衡量惯性与毛细作用的相对大小。理论得到了精确数值模拟的支持，给出$r_j\propto\tau^{\alpha(\beta)}$，其中$\alpha\simeq0.63$，因此$We_j\gg1$，当$r_j\to0$时$We_j\to\infty$，即惯性逐渐超过毛细作用。在模拟中，当长度按我们对$r_j$的预测进行缩放时，界面在无量纲时间内坍塌成一种通用形状超过二十年。对于水，这给出了$\mathcal{O}(1)$纳米的初始半径，预测了纳米级的海喷雾气溶胶。
英文摘要
When a micron-sized bubble bursts, capillary waves deform the cavity into a cone that ejects a Worthington jet. The jet is born by inertial focusing, and the local collapse follows self-similar Euler solutions set by the semiangle $β$. Writing $r_j$ and $v_j$ for the dimensionless jet-base radius and velocity, the local Weber number $We_j=r_j v^2_j$ measures inertia relative to capillarity. The theory, supported by accurate numerical simulations gives $r_j\proptoτ^{α(β)}$ with $α\simeq0.63$ and, hence $We_j\gg1$, with $We_j\to\infty$ as $r_j\to0$, so inertia increasingly overwhelms capillarity. In simulations, the interface collapses onto a universal shape for more than two decades in dimensionless time when lengths are scaled using our prediction for $r_j$. For water, this gives incipient radii of $\mathcal{O}(1)$ nm, predicting nanometric sea-spray aerosols.
