Electrokinetic energy conversion through cylindrical microannulus with periodic heterogeneous wall potentials
Electrokinetic energy conversion through cylindrical microannulus with periodic heterogeneous wall potentials
复制标题
通过具有周期性异质壁电位的圆柱形微环进行动电能量转换
DOI：
10.1088/1361-6463/ac45ae
复制
发表时间：
2022-04-07
影响因子：
3.4
通讯作者：
Jian, Yongjun
中科院分区：
文献类型：
--
作者：
Chu, Xin;Jian, Yongjun
In microfluidic electrokinetic flows, heterogeneous wall potentials are often required to fulfill some functions, such as increasing dispersion and mixing efficiency. In this paper, we study the pressure-driven electrokinetic flow through microannulus with heterogeneous wall potentials in circumferential direction. The streaming potential induced by the ions accumulating in downstream of the microannulus is considered and the electrokinetic energy conversion (EKEC) efficiency is further investigated. Interestingly, based on the method of Fourier expansion, the analytical solutions of fluid velocity, streaming potential and energy conversion efficiency are derived for arbitrary peripheral distribution of the small wall potential for the first time. Four specific patterned modes of the heterogeneous wall potential, i.e. constant, step, sinusoid with period 2π and sinusoid with period π/2 are represented. The distributions of the electric potential and the velocity for four different modes are depicted graphically. Furthermore, the variations of the streaming potential and the EKEC conversion efficiency with related parameters are also discussed. Results show that when these integral values from −π to π associated with the wall potentials are identical, the streaming potential and the EKEC efficiency corresponding to different modes are the same. Additionally, the amplitude of fluid velocity peripherally reduces with the increase of the wavenumber of wall potential distribution in θ-direction.
