Separation of microparticles is of great importance in diagnostic, chemical, and biological analysis, as well as food processing and environmental assessments. In the present work, a novel microfluidic device is designed to focus microparticles based on inertial and magnetophoretic impacts. Three permanent magnets are mounted in the vicinity of the microchannel to separate the diamagnetic particles suspended in a ferrofluid by applying a negative magnetophoretic force. Polystyrene particles with three sizes of 5, 10, and 15 µm are separated from each other using the proposed device with 100% separation efficiency. The results show that high purity of particle collection can be achieved using Halbach array of magnets at Reynolds numbers of 100 and 110. The influence of inlet flow velocity, magnets’ configuration, and their distance from the microchannel is investigated and the optimal situations are determined.

微粒的分离在诊断、化学和生物分析以及食品加工和环境评估中非常重要。在目前的工作中，一种新型微流体装置被设计为基于惯性和磁泳影响来聚焦微粒。三个永磁体安装在微通道附近，通过施加负磁泳力来分离悬浮在铁磁流体中的抗磁性颗粒。使用建议的设备以 100% 的分离效率将具有 5、10 和 15 µm 三种尺寸的聚苯乙烯颗粒相互分离。结果表明，在雷诺数为 100 和 110 的情况下，使用 Halbach 磁体阵列可以实现高纯度的颗粒收集。入口流速、磁体配置、