Department of Mechanical Engineering, Manipal University Jaipur, Rajasthan 303007, India.
Department of Mechanical Engineering, Manipal University Jaipur, Rajasthan 303007, India.
Microvasc Res. 2017 Nov;114:65-83. doi: 10.1016/j.mvr.2017.06.004. Epub 2017 Jun 12.
A theoretical study is presented here for the electro-osmosis modulated peristaltic three-layered capillary flow of viscous fluids with different viscosities in the layers. The layers considered here are the core layer, the intermediate layer and the peripheral layer. The analysis has been carried out under a number of physical restrictions viz. Debye-Hückel linearization (i.e. wall zeta potential ≤25mV) is assumed sufficiently small, thin electric double layer limit (i.e. the peripheral layer is much thicker than the electric double layer thickness), low Reynolds number and large wavelength approximations. A non-dimensional analysis is used to linearize the boundary value problem. Fluid-fluid interfaces, peristaltic pumping characteristics, and trapping phenomenon are simulated. Present study also evaluates the responses of interface, pressure rise, time-averaged volume flow rate, maximum pressure rise, and the influence of Helmholtz-Smoluchowski velocity on the mechanical efficiency (with two different cases of the viscosity of fluids between the intermediate and the peripheral layer). Trapping phenomenon along with bolus dynamics evolution with thin EDL effects are analyzed. The findings of this study may ultimately be useful to control the microvascular flow during the fractionation of blood into plasma (in the peripheral layer), buffy coat (intermediate layer) and erythrocytes (core layer). This work may also contributes in electrophoresis, hematology, electrohydrodynamic therapy and, design and development of biomimetic electro-osmotic pumps.
本文针对不同层间粘度的粘性流体在电渗调制下的三层蠕动层流进行了理论研究。这里考虑的层是核心层、中间层和外围层。分析中考虑了一些物理限制,例如假设 Debye-Hückel 线性化(即壁面 ζ 电位≤25mV)足够小、薄电双层限制(即外围层比电双层厚度大得多)、低雷诺数和大波长近似。使用无量纲分析对边值问题进行线性化。模拟了流-流界面、蠕动泵送特性和捕获现象。本研究还评估了界面、压力上升、时均体积流量、最大压力上升以及亥姆霍兹-斯莫卢霍夫速度对机械效率的影响(中间层和外围层之间的两种不同流体粘度情况)。分析了薄 EDL 效应下的捕获现象以及 bolus 动力学演化。这项研究的结果最终可能有助于控制血液在血浆(外围层)、白细胞层(中间层)和红细胞(核心层)分离过程中的微血管流动。这项工作还可能有助于电泳、血液学、电动治疗以及仿生电渗流泵的设计和开发。