Three-dimensional and analytical modeling of microfluidic particle transport in magnetic fluids
Three-dimensional and analytical modeling of microfluidic particle transport in magnetic fluids
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DOI：
10.1007/s10404-013-1280-z
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发表时间：
2014-06-01
影响因子：
2.8
通讯作者：
Mao, Leidong
中科院分区：
文献类型：
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作者：
Cheng, Rui;Zhu, Taotao;Mao, Leidong
我们提出了一个分析模型，可以预测的三维（3D）的非磁性颗粒在磁性流体内的微流体通道耦合永磁体的运输。磁体产生空间上不均匀的磁场，该磁场在颗粒上产生磁浮力。通过（1）经由磁场及其梯度的解析分布以及磁性流体的非线性磁化模型计算施加在颗粒上的3D磁浮力，（二）用低雷诺数铁流体动力学流动的分析速度分布导出颗粒上的3D流体动力学粘性阻力，考虑磁流体的“壁面效应”和磁粘性效应的磁流体通道;（3）利用磁浮力和流体动力粘性阻力的解析表达式，建立并求解颗粒的运动控制方程。我们使用这样的模型来研究粒子在通道中的轨迹，并调查在不同的流量，不同的磁性流体的性质和不同的几何参数的系统的偏转的大小。
We present an analytical model that can predict the three-dimensional (3D) transport of non-magnetic particles in magnetic fluids inside a microfluidic channel coupled with permanent magnets. The magnets produce a spatially non-uniform magnetic field that gives rise to a magnetic buoyancy force on the particles. Resulting 3D trajectories of the particles are obtained by (1) calculating the 3D magnetic buoyancy force exerted on the particles via an analytical distribution of magnetic fields as well as their gradients, together with a nonlinear magnetization model of the magnetic fluids, (2) deriving the 3D hydrodynamic viscous drag force on the particles with an analytical velocity profile of a low Reynolds number ferrohydrodynamic flow in the channel including "wall effect'' and magnetoviscous effect of the magnetic fluids, and (3) constituting and solving the governing equations of motion for the particles using the analytical expressions of magnetic buoyancy force and hydrodynamic viscous drag force. We use such a model to study the particles' trajectories in the channel and investigate the magnitude of their deflections at different flow rates, with different properties of magnetic fluids and different geometrical parameters of the system.