表面自由能模型的改进及液滴浸润数值研究

通过优化极值点位置,对表面自由能模型进行了研究和改进,改进后的模型解决了原模型中表面粒子聚集和液滴形状畸变的问题.采用移动粒子半隐式法(MPS)结合改进后的表面自由能模型,对受表面张力作用的自由面运动问题进行了研究和分析.研究了包括气液、固液和不互溶液液界面在内的表面张力收缩和液滴浸润过程,并提取了接触角及浸润面积等特征量进行分析.数值计算结果与理论分析结果吻合较好,从结果中可以明显观察到固液浸润过程的3个发展阶段,浸润速度随时间递减且与浸润接触角成反比.研究结果验证了MPS方法结合改进后的表面自由能模型可以更加有效、准确地模拟多界面张力的作用.

Improvement of Surface Tension Model and Numerical Investigation on Droplet Wetting Effect

An improved surface tension model was obtained by optimizing the position of the extreme point.The particle clustering and shape distortion problems were solved by the model improved.The moving particle semi-implicit(MPS) method combined with the improved model was adopted to simulate the wetting phenomenon with large deformation of the free surface.The shrinkage and wetting effect,due to the surface tension,between different substances(gas-liquid,solid-liquid or liquid-liquid) was examined and analyzed.The wetting angle and wetting area were extracted for analysis.The numerical result agrees well with the analytical one.Three sections could be observed in the liquid-solid wetting process.The wetting speed decreases with an increase in time and varies inversely with the wetting angle.Our results indicate that the MPS method combined with the improved surface tension model can simulate the interface tension force between different substances effectively and precisely.