Chubynsky Mykyta V, Belousov Kirill I, Lockerby Duncan A, Sprittles James E
Mathematics Institute, University of Warwick, Coventry CV4 7AL, United Kingdom.
Faculty of Physics and Engineering, ITMO University, St. Petersburg 197101, Russia.
Phys Rev Lett. 2020 Feb 28;124(8):084501. doi: 10.1103/PhysRevLett.124.084501.
A model is developed for liquid drop impact on a solid surface that captures the thin film gas flow beneath the drop, even when the film's thickness is below the mean free path in the gas so that gas kinetic effects (GKE) are important. Simulation results agree with experiments, with the impact speed threshold between bouncing and wetting reproduced to within 5%, while a model without GKE overpredicts this value by at least 50%. To isolate GKE, the pressure dependence of the threshold is mapped and provides experimentally verifiable predictions. There are two principal modes of contact leading to wetting and both are associated with a van der Waals driven instability of the film.
开发了一种用于液滴撞击固体表面的模型，该模型能够捕捉液滴下方的薄膜气流，即使薄膜厚度低于气体中的平均自由程，以至于气体动力学效应（GKE）很重要。模拟结果与实验结果相符，弹跳和润湿之间的撞击速度阈值的再现误差在5%以内，而没有考虑GKE的模型对该值的预测至少高估了50%。为了分离出GKE，绘制了阈值的压力依赖性，并提供了可通过实验验证的预测。有两种导致润湿的主要接触模式，且两者都与薄膜的范德华驱动不稳定性有关。
