Dynamic flow characteristics in U-type anti-high overload microfluidic inertial switch
Dynamic flow characteristics in U-type anti-high overload microfluidic inertial switch
复制标题
DOI：
10.1007/s10404-019-2194-1
复制
发表时间：
2019-03-01
影响因子：
2.8
通讯作者：
Xie, Jinlong
中科院分区：
文献类型：
--
作者：
Shen, Teng;Li, Jiajie;Xie, Jinlong
在单向惯性力的作用下，工作液可以承受高过载而不分散在u型连接的微通道中。该结构为设计抗高过载微流控惯性开关提供了可能。基于所设计的u型微流控惯性开关，研究了u型微通道内液体在惯性力作用下的动态流动过程，以预测和评价其抗过载特性。利用未定因子k，推导了考虑黏性局部阻力影响的非定常伯努利流动模型，利用CFD软件中的VOF和CSD模块对瞬态流动过程进行分析，并通过仿真结果得到因子k。利用离心试验平台测量液体表面运动位移的变化。结果表明：修正后的动态流动模型能较好地描述液面流动过程，且液面振荡频率和振幅随惯性加速度和微通道截面尺寸的增大而增大。而且，即使在3000g的载荷下，液体也不会出现分散，这表明u型结构惯性开关具有抗高过载的特性。
Under the action of unidirectional inertial force, the working liquid can bear high overload and not be dispersed in the U-type connected microchannel. This structure provides the possibility for designing anti-high overload microfluidic inertial switch. Based on the designed U-type microfluidic inertial switch, the dynamic flow process of liquid in U-type microchannel under inertial force was studied to predict and evaluate the characteristic of anti-overload. The unsteady Bernoulli flow model with the effect of viscosity local resistance was derived by utilizing the undetermined factor k. The VOF and CSD modules in CFD software were employed to analyze the transient flow process, and then the factor k was obtained by the simulation results. Centrifugal test platform was utilized to measure the variation of liquid surface movement displacement. The result shows that the modified dynamic flow model can reasonably describe the flow process of liquid surface, and the oscillations frequency and amplitude of the liquid surface increase with the increase of the inertial acceleration and the cross-sectional size of the microchannel. Moreover, even under the load of 3000g, the liquid does not appear to be dispersed, which indicates that the U-type structure inertial switch has the characteristics of anti-high overload.