非均质壁面对液滴俘获能力的数值模拟研究

为研究不同非均质壁面对液滴的俘获能力，采用界面追踪法（FTM）结合广义滑移边界建立了接触角模型，对液滴在非均匀润湿的非均质壁面上的运动过程进行了数值模拟研究。液滴在倾斜壁面上受到重力作用由均匀润湿部分下滑至非均匀润湿部分，通过改变Bo数、Oh数、非均匀润湿程度研究了液滴在非均匀润湿区域的运动规律。研究表明：Bo数越大，液滴运动受壁面阻力影响越小，液滴下滑的速度越快，液滴越难以被俘获；Oh数越大，液滴运动受壁面阻力影响越小，液滴越难以被俘获；非均匀润湿程度越大，非均质壁面对液滴的阻力越大，液滴越易被俘获。

Numerical simulation of drop capturing capabilities on heterogeneous walls

In order to study the drop capturing capabilities of heterogeneous walls, a numerical method is developed by integrating the generalized Navier boundary condition into front tracking method (FTM) to establish the contact angle model. The numerical simulation of the movement of drops on the heterogeneous wall with non-uniform wetting was carried out. The drop slides on the inclined wall from the uniform wetting part to the non-uniform wetting part. The movement of the drop in the non-uniform wetting area is studied by changing the Bo number, the Oh number and the non-uniform wetting degree. the results show that when the Bo number becomes lager, the movement of drop will be less affected by the resistance of the wall and the velocity of the drop will become larger which makes it difficult to be captured; the greater the Oh number is, the less effect of wall surface resistance on the drop is, and the more difficult it is to capture the drop; when the non-uniform wetting degree becomes lager, the resistance of the heterogeneous wall to drop will be greater, and the drop will be captured more easily.