基于磁流体力学的微流控研究
发布时间：2019-01-08 10:56
【摘要】：为了提升传统磁流体力学微泵在微流体系统中的表现,通过集成平面电磁铁实现磁流体力学微泵的微型化。对构建的新型磁流体力学微泵进行仿真模拟,获得优化的结构设计。采用微加工方法实现磁流体力学微泵的制作,并将磁流体力学微泵与阻抗传感器进行集成,实现了对无机溶液和生物样品的抽吸和实时阻抗测试功能,结果表明制作的磁流体力学微泵能够应用于生物检测领域。通过对建立的磁流体力学微泵进行COMSOL软件仿真模拟,耦合多个物理场,包括电磁模块、热力学模块和层流模块,研究磁流体力学微泵的基本原理。本文研究了在平面电磁铁磁流体力学微泵中,流速、磁通密度在不同深宽比微通道中的分布；不同线圈材料和磁轭材料对磁流体力学微泵抽吸性能的影响；研究了焦耳热、电渗效应和壁面滑移条件对磁流体力学微泵的影响。结果表明深宽比为1：1的微通道具有较优表现,能够达到0.94mL/min的流速。在壁面滑移长度为10μm的条件下,流速能够达到16.3mm/s。随着滑移长度从10μm增至90μm,流体的平均温度从36.0℃降至30.2℃。利用有限元分析研究不同的电磁线圈形状和磁轭材料对电磁铁性能的影响,采用微加工方法制作实际的平面型电磁铁,并且通过磁性颗粒进行表征,研究制作的平面电磁铁对磁性颗粒的控制能力。结果表明蜿蜒型的线圈结构能够产生大的磁场梯度,方形和圆形的线圈结构均能产生较均匀的磁场。具有较高磁导率的磁轭材料能够产生较强的磁场,但是为了产生Z轴方向的磁场,需要求磁轭材料具有垂直磁化能力。本文采用CoFeB合金作为磁轭材料,通过与常用的镍材料的对比,结果表明CoFeB合金作为磁轭材料具有较强的垂直磁化性能,能够有效地进行磁性颗粒的控制。将制作的电磁铁和电极集成,成功制作磁流体力学微泵,并进行聚苯乙烯微球的抽吸,结果表明制作的磁流体力学微泵能够有效抽吸样品溶液。通过与其它各类传感元件的集成,研发的磁流体力学微泵还能够实现更加灵活的控制和更广泛的应用,如具有应用于药物缓释系统、生化分析和环境检测等领域的潜力。本文研究了阻抗传感器与新型的磁流体力学微泵的集成,采用SU-8与PDMS进行完整密封,以实现在同一晶片上实现样品的预处理与样品检测的功能。分别制作了四种不同结构的电极,采用电化学工作站对不同浓度的盐溶液、不同浓度的聚苯乙烯微球溶液、不同粒径大小的聚苯乙烯微球溶液和不同浓度的细胞溶液在1Hz至100kHz范围内进行了阻抗测试,研究分析不同电极结构对阻抗测试的影响。结果表明叉指型电极具有较高的灵敏度,能够有效区别不同浓度的细胞溶液。
[Abstract]:In order to improve the performance of the traditional MHD micropump in the microfluid system, the magnetohydrodynamic micropump is miniaturized by integrating the planar electromagnet. The new MHD micropump was simulated and optimized structure design was obtained. The fabrication of MHD micropump is realized by using micromachining method. The MHD micropump is integrated with impedance sensor to realize the functions of suction and real time impedance measurement of inorganic solution and biological sample. The results show that the MHD micropump can be used in the field of biological detection. The basic principle of MHD micropump was studied by COMSOL software simulation and coupled with many physical fields, including electromagnetic module, thermodynamics module and laminar flow module. In this paper, the distribution of velocity and flux density in different aspect ratio microchannels in planar electromagnet magnetohydrodynamic micropump, the influence of different coil materials and magnetic yoke materials on the pumping performance of magnetic fluid micropump are studied. The effects of Joule heat, electroosmotic effect and wall slip conditions on MHD micropump were studied. The results show that the microchannel with a aspect ratio of 1:1 has a better performance and can reach the flow rate of 0.94mL/min. When the slip length of the wall is 10 渭 m, the velocity of flow can reach 16.3 mm / s. With the slip length increasing from 10 渭 m to 90 渭 m, the average temperature of the fluid decreases from 36.0 鈩，
本文编号：2404509
[Abstract]:In order to improve the performance of the traditional MHD micropump in the microfluid system, the magnetohydrodynamic micropump is miniaturized by integrating the planar electromagnet. The new MHD micropump was simulated and optimized structure design was obtained. The fabrication of MHD micropump is realized by using micromachining method. The MHD micropump is integrated with impedance sensor to realize the functions of suction and real time impedance measurement of inorganic solution and biological sample. The results show that the MHD micropump can be used in the field of biological detection. The basic principle of MHD micropump was studied by COMSOL software simulation and coupled with many physical fields, including electromagnetic module, thermodynamics module and laminar flow module. In this paper, the distribution of velocity and flux density in different aspect ratio microchannels in planar electromagnet magnetohydrodynamic micropump, the influence of different coil materials and magnetic yoke materials on the pumping performance of magnetic fluid micropump are studied. The effects of Joule heat, electroosmotic effect and wall slip conditions on MHD micropump were studied. The results show that the microchannel with a aspect ratio of 1:1 has a better performance and can reach the flow rate of 0.94mL/min. When the slip length of the wall is 10 渭 m, the velocity of flow can reach 16.3 mm / s. With the slip length increasing from 10 渭 m to 90 渭 m, the average temperature of the fluid decreases from 36.0 鈩，
本文编号：2404509
本文链接：https://www.wllwen.com/shoufeilunwen/jckxbs/2404509.html
