三維晶格波茲曼法結合親/疏水性邊界模擬液氣兩相流之流場

3D Lattice Boltzmann Simulations of Incompressible Liquid-Gas system on Partial Wetting Surface

吳承隆

指導教授 ： 林昭安

國立清華大學/工學院/動力機械工程學系/碩士(2010年)

https://doi.org/10.6843/NTHU.2010.00388

摘要

In this thesis, a 3D lattice Boltzmann multiphase fluid model based on D3Q19 which is capable of dealing two phase flow with large density ratio and partial wetting surface with a given contact angle is investigated. Multiphase fluid behavior can be simulated using the Navier-Stokes
equation coupling with convective Cahn-Hilliard equation [35], where the latter equation is used to capture the interface of multiphase fluid in terms of chemical potential. By adopting the free-energy model and adding an additional term into the total free energy to describe surface energy, a droplet rests on a surface with given contact angle can be simulated.
The capability of the present model, which is to compute two phase flow with wettability controllable surface, is validated by simulating a droplet that rests on a surface with given contact angle. The contact angles calculated from the results agree with theory. The effect of gravitational force on droplet shape is also discussed in terms of Bond number.
The present model is applied to simulate liquid lens cases. The simulation result shows good compatibility with the experiment done by Hsieh et al. [70], where Bond number is about 1.3.

關鍵字

三維 ； 晶格波茲曼 ； 高密度比 ； 兩相流 ； 親水性 ； 疏水性 ； 液滴

參考文獻

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