School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran.
Phys Rev E. 2019 Aug;100(2-1):023105. doi: 10.1103/PhysRevE.100.023105.
In this work, numerical simulations are performed to study the droplet response to the vertical vibration of the substrate, under various frequencies and amplitudes using the multiphase lattice Boltzmann method. First, the numerical results are validated against published experimental data. The effects of droplet size, surface wettability, amplitude, and frequency of the vibrating substrate on droplet detachment are studied. For high contact angles, regardless of the droplet size, when the vibration frequency matches the droplet resonance frequency the droplet is easily removed from the surface. For lower contact angles, the resonance frequency is higher and the detachment amplitude increases significantly. It was also found that viscous forces do not affect the resonance frequency, but have a noticeable impact on the detachment amplitude. The findings of this study can be useful in applications where droplet shedding is crucial, e.g., condensation heat transfer.
本文采用多相格子 Boltzmann 方法，针对基底的垂直振动，在不同频率和幅值下，对液滴的响应进行了数值模拟。首先，通过与已发表的实验数据进行对比，验证了数值结果的可靠性。研究了液滴尺寸、表面润湿性、基底振动幅值和频率对液滴脱离的影响。对于高接触角，无论液滴尺寸如何，当振动频率与液滴的共振频率相匹配时，液滴很容易从表面脱离。对于较低的接触角，共振频率较高，脱离振幅显著增加。此外，还发现粘性力并不影响共振频率，但其对脱离振幅有显著影响。本研究的结果对于那些需要液滴脱落的应用（如冷凝传热）可能具有重要意义。
