摘要
通过数值模拟研究了方柱阵列Cassie态超疏水表面通道的压力驱动流,对比了单相流(“黏滑”复合壁面条件)和气液两相流模拟的结果。计算结果表明:Cassie态超疏水壁面对流场结构具有较大影响,固壁面积占比越大,流速越低,截面流量越小;空气面积占比越大,滑移减阻效应越明显;两种数值模拟方法所获有效滑移长度变化规律趋于一致,但由于微柱间气体具有黏性作用,气液两相数值模拟的速度低于不考虑气体黏性的单相流模型,导致前者有效滑移长度总是小于单相流模型;流体介质为水时,滑移长度最小相对偏差约32%,表明用无黏性气体的理想模型代替考虑气体黏性影响的模型存在较大局限性。
The pressure-driven flow of Cassie-state superhydrophobic surface channels in square pillar arrays is studied through numerical simulation,and the results from single-phase flow simulations(using a“stick-slip”composite wall condition)and gas-liquid two-phase flow simulations are compared.The calculation results show that the Cassie-state superhydrophobic wall has a significant influence on the flow field structure.The larger the proportion of solid wall area,the lower the flow velocity,and the smaller the cross-sectional flow rate.The larger the proportion of air area,the more obvious the slip drag reduction effect.The effective slip length obtained by the two numerical simulation methods tends to be consistent,but due to the viscous effect of gas between micro-pillars,the velocity of gas-liquid two-phasenumerical simulation is lower than that of the single-phase flow model without considering gas viscosity,resulting in the effective slip length of former always being lower than that of single-phase flow model.When the fluid medium is water,the minimum relative deviation of slip length reaches approximately 32%,demonstrating that there are significant limitations to using an ideal gas model for non-viscous gases instead of considering the influence of gas viscosity.
作者
谢嘉澳
王昊利
XIE Jiaao;WANG Haoli(Jinling Institute of Technology,Nanjing 211169,China)
出处
《金陵科技学院学报》
2025年第2期71-78,共8页
Journal of Jinling Institute of Technology
基金
国家自然科学基金面上项目(11872027)。
关键词
微柱体阵列
超疏水
有效滑移长度
微通道流场
micro-pillar array
superhydrophobic
effective slip length
microchannel flow field
