Lixiang Lv, Yibiao Chen, Yangyang Jiang, Gulite Wang, Jiacheng Lu
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引用次数: 0
Abstract
Microfluidic technology is widely applied in biological detection, primarily utilizing microvalves to control and regulate fluid flow. Increasing attention and research have recently been directed toward magnetic droplet valves, which use magnetic fields to control magnetic droplets in microchannels for sealing purposes. A novel droplet formation technique has been proposed, employing a permanent magnet to attract magnetic fluid through a step emulsification process, thus controllably forming the magnetic droplets required for microvalves. However, the current understanding of the generation mechanism of magnetic fluid step emulsification remains insufficiently deep, with inadequate force analysis during the expansion stage of the magnetic fluid. This shortcoming results in an unclear comprehension of the relationship between the magnetic field and step emulsification formation, impeding the accurate prediction and control of droplet size and formation rate, thereby compromising the performance and reliability of magnetic droplet valves. Therefore, the study initially analyzes the forces acting on the magnetic fluid in a non-uniform magnetic field theoretically and systematically explores the step emulsification mechanism of magnetic fluids through a combination of numerical simulations and experimental validations. The magnetic field inhomogeneity degree directly affects the microdroplet formation process. As the lateral distance between the permanent magnet and the channel outlet increases, the magnetic field inhomogeneity degree decreases, resulting in larger droplet volumes and lower formation rates. Through theoretical analysis and experimental validation, this study provides a significant theoretical foundation and practical guidance for forming magnetic fluid in microfluidic systems.
期刊介绍:
Microfluidics and Nanofluidics is an international peer-reviewed journal that aims to publish papers in all aspects of microfluidics, nanofluidics and lab-on-a-chip science and technology. The objectives of the journal are to (1) provide an overview of the current state of the research and development in microfluidics, nanofluidics and lab-on-a-chip devices, (2) improve the fundamental understanding of microfluidic and nanofluidic phenomena, and (3) discuss applications of microfluidics, nanofluidics and lab-on-a-chip devices. Topics covered in this journal include:
1.000 Fundamental principles of micro- and nanoscale phenomena like,
flow, mass transport and reactions
3.000 Theoretical models and numerical simulation with experimental and/or analytical proof
4.000 Novel measurement & characterization technologies
5.000 Devices (actuators and sensors)
6.000 New unit-operations for dedicated microfluidic platforms
7.000 Lab-on-a-Chip applications
8.000 Microfabrication technologies and materials
Please note, Microfluidics and Nanofluidics does not publish manuscripts studying pure microscale heat transfer since there are many journals that cover this field of research (Journal of Heat Transfer, Journal of Heat and Mass Transfer, Journal of Heat and Fluid Flow, etc.).