AI 中文总结
研究液滴序列的一维弹道聚集，通过实验和模拟证实其由单一长度尺度控制，揭示空气阻力及一维排序约束对其特征的影响，还表明类似斯莫卢霍夫斯基的平均场描述在特定情况下失效。
AI 中文摘要
弹道聚集是一个典型的非平衡过程，在从颗粒气体到行星吸积的各个尺度上都有相关性。碰撞由速度差异驱动，在相邻粒子间建立起持久的相关性。本文首次在由液体射流破碎形成的液滴序列中实现了一维弹道聚集的实验。实验和模拟证实了分析预测的标度关系，表明全局过程由单一长度尺度控制。虽然空气阻力使相邻粒子速度相关性的符号反转，但一维排序约束保护了弹道聚集的整体特征，如标度指数和大质量尾部的形状。更广泛地说，我们的结果表明，当碰撞带有方向记忆时，类似斯莫卢霍夫斯基的平均场描述会失效，正如这里对射流产生的喷雾所证明的那样。
英文摘要
Ballistic aggregation is a canonical non-equilibrium process, relevant across scales from granular gases to planetary accretion. Collisions are driven by differences in velocities, building up persistent correlations between neighbors. Here, we provide the first experimental realization of one-dimensional ballistic aggregation in a train of droplets formed by the breakup of a liquid jet. Experiments and simulations confirm the analytically predicted scaling, with the global process shown to be governed by a single length scale. While air drag inverts the sign of neighbor velocity correlations, a 1D ordering constraint protects bulk characteristics of ballistic aggregation such as the scaling exponent and the shape of the large mass tail. More broadly, our results show that Smoluchowski-like mean-field descriptions fail when collisions carry directional memory -- as demonstrated here for jet-generated sprays.
