Electroviscous effect and electrokinetic energy conversion in time periodic pressure-driven flow through a parallel-plate nanochannel with surface charge-dependent slip
Electroviscous effect and electrokinetic energy conversion in time periodic pressure-driven flow through a parallel-plate nanochannel with surface charge-dependent slip
复制标题
时间周期压力驱动流通过具有表面电荷依赖滑移的平行板纳米通道时的电粘性效应和动电能转换
DOI：
10.1088/1361-6463/aabc73
复制
发表时间：
2018-05-23
影响因子：
3.4
通讯作者：
Chang, Long
中科院分区：
文献类型：
--
作者：
Buren, Mandula;Jian, Yongjun;Chang, Long
在本文中，我们解析地研究了不可压缩粘性牛顿液体通过具有表面电荷相关滑移的平行板纳米通道的时间周期压力驱动流动中的电粘性效应和电动动能转换。得到了电势、速度和流动电场的解析和半解析解，并将其用于电动动能转换效率的计算。结果表明，当考虑表面电荷对滑移长度的影响时，速度幅值和能量转换效率降低。表面电荷效应随Zeta电位和离子浓度的增加而增大。此外，当沟道半高与电双层厚度之比较小时，能量转换效率较高。边界滑移导致了能量转换的大幅度增加。压力脉动频率越高，能量转换效率越高。我们还得到了恒压驱动流的能量转换效率，发现当频率足够大时，周期压力驱动流的能量转换效率比恒压驱动流的能量转换效率更大。
In this paper we analytically investigate the electroviscous effect and electrokinetic energy conversion in the time periodic pressure-driven flow of an incompressible viscous Newtonian liquid through a parallel-plate nanochannel with surface charge-dependent slip. Analytical and semi-analytical solutions for electric potential, velocity and streaming electric field are obtained and are utilized to compute electrokinetic energy conversion efficiency. The results show that velocity amplitude and energy conversion efficiency are reduced when the effect of surface charge on slip length is considered. The surface charge effect increases with zeta potential and ionic concentration. In addition, the energy conversion efficiency is large when the ratio of channel half-height to the electric double layer thickness is small. The boundary slip results in a large increase in energy conversion. Higher values of the frequency of pressure pulsation lead to higher values of the energy conversion efficiency. We also obtain the energy conversion efficiency in constant pressure-driven flow and find that the energy conversion efficiency in periodical pressure-driven flow becomes larger than that in constant pressure-driven flow when the frequency is large enough.