摘要
通过开展湍流状态下超疏水表面流场的非稳态数值仿真,给出了超疏水表面气层发展变化过程,并总结出其流动发展稳定时的减阻基本规律。数值仿真中,采用适用于超疏水表面流场特点的非定常雷诺平均模型,气液两相流则采用VOF多相流模型,超疏水微结构表面网格剖分采用局部加密技术。研究结果表明:超疏水表面微结构内部气体随流动不断变化,最终在每个凹槽的中上部形成稳定存在的气体漩涡;超疏水表面减阻率随来流速度增加先增大而后降低,随表面自由剪切比的增大而增大,而受凹槽深度影响不显著。
An unsteady numerical simulation of a turbulent water flow field on a super-hydrophobic sur face shows the development of the gas membranes process on the hydrophobic surface, and the resistance re duction basic rule is summed up when the flow changes are stable. In the simulation, the unsteady Reynolds averaged model is used, the VOF multiphase flow model is used for the gas-liquid two phase flow, and a hy drophobic surface microstructure grid with local encryption technology is adopted. The results show that the gas in the micro-structure of hydrophobic surface changes continuously, a stable gas vortex forms at last in the upper part of each groove; the drag reduction rate of the hydrophobic surface first increases and then de creases with the flow rate increase; it also increases with the free shear ratio increase, but it is not signifi- cantly affected by the groove depth.
出处
《空气动力学学报》
CSCD
北大核心
2013年第3期326-332,共7页
Acta Aerodynamica Sinica
基金
国家自然科学基金重点项目(50835009)
国家自然科学基金项目(51109178)
陕西省自然科学基础研究计划项目(2010JQ1009)
关键词
湍流
超疏水表面
非稳态
减阻
turbulent flow
super hydrophobic surface
unsteady
drag reduction
