摘要
在传统的流体力学中,流体在固壁处流速为零,即无滑移边界条件。在微纳米条件下,由于固液界面作用力增大,无滑移边界条件不再适用。该文首先从微米石英圆管中的流动实验现象出发,给出润湿性边界黏滞层厚度随应力变化的边界模型。在此基础上推导出层流条件下,微纳米管中的流量公式,并对流量公式进行渐近分析,同时也分析流动微纳米尺度下的流动特征。最后用微米圆管中去离子水的流动实验,对新建的理论模型进行验证。研究表明:润湿性条件下,边界黏滞层厚度随驱动力的增大而减小;新建立的微纳米尺度下的边界模型和流量公式非常符合实验结果,其中一次方的流量模型应用时更为简单,在压力梯度较小时,指数项起作用产生了非线性流动的效果。
The traditional theory of fluid mechanics shows that the velocity of liquid flow near solid boundary is zero, which is called as no-slip boundary condition. But it cannot be apt to the liquid flow in micro- and nano- structures because of the huge specific surface and the interface force of liquid and solid. First the model of height of liquid boundary adhesion zone changed with external force was given on basis of experiments of liquid flow in micro-tubes. Then the formulae of flow velocity and flow rate were derived for hydrophilic fluid. Finally the new formulae were testified by experiments of deionized water flow in silica micro-tubes. The results show that： the height of liquid boundary adhesion zone becomes smaller with the external force increasing. The new formulae of flow velocity and flow rate is suitable for water flow experiments in silica micro-tubes, application of one of the power flow model is more simple, the pressure gradient is small, the index item works the effect of nonlinear flow.
出处
《水动力学研究与进展（A辑）》
CSCD
北大核心
2016年第5期615-620,共6页
Chinese Journal of Hydrodynamics
基金
国家自然科学基金(11472246)
国家重点基础研究发展计划(2013CB228002)~~
关键词
微纳米流动
微管
边界条件
边界黏滞层
micro-and nano-flow
micro-tube
boundary condition
boundary adhesion zone
