Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow
We numerically investigate the dynamics of a pair of circular Janus microparticles immersed in a Newtonian fluid under a simple shear flow and a uniform magnetic field by direct numerical simulation. Using the COMSOL software, we applied the finite element method, based on an arbitrary Lagrangian-Eu...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-01-01
|
| Series: | Magnetochemistry |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2312-7481/7/1/16 |
| _version_ | 1797409864971976704 |
|---|---|
| author | Christopher Sobecki Jie Zhang Cheng Wang |
| author_facet | Christopher Sobecki Jie Zhang Cheng Wang |
| author_sort | Christopher Sobecki |
| collection | DOAJ |
| description | We numerically investigate the dynamics of a pair of circular Janus microparticles immersed in a Newtonian fluid under a simple shear flow and a uniform magnetic field by direct numerical simulation. Using the COMSOL software, we applied the finite element method, based on an arbitrary Lagrangian-Eulerian approach, and analyzed the dynamics of two anisotropic particles (i.e., one-half is paramagnetic, and the other is non-magnetic) due to the center-to-center distance, magnetic field strength, initial particle orientation, and configuration. This article considers two configurations: the LR-configuration (magnetic material is on the left side of the first particle and on the right side of the second particle) and the RL-configuration (magnetic material is on the right side of the first particle and on the left side of the second particle). For both configurations, a critical orientation determines if the particles either attract (below the critical) or repel (above the critical) under a uniform magnetic field. How well the particles form a chain depends on the comparison between the viscous and magnetic forces. For long particle distances, the viscous force separates the particles, and the magnetic force causes them to repel as the particle orientation increases above the configuration’s critical value. As the initial distance decreases, a chain formation is possible at a steady orientation, but is more feasible for the RL-configuration than the LR-configuration under the same circumstances. |
| first_indexed | 2024-03-09T04:21:44Z |
| format | Article |
| id | doaj.art-38548a685eb449cd8a00815e6f834930 |
| institution | Directory Open Access Journal |
| issn | 2312-7481 |
| language | English |
| last_indexed | 2024-03-09T04:21:44Z |
| publishDate | 2021-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Magnetochemistry |
| spelling | doaj.art-38548a685eb449cd8a00815e6f8349302023-12-03T13:46:39ZengMDPI AGMagnetochemistry2312-74812021-01-01711610.3390/magnetochemistry7010016Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear FlowChristopher Sobecki0Jie Zhang1Cheng Wang2Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 400 W. 13th St., Rolla, MO 65409, USADepartment of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 400 W. 13th St., Rolla, MO 65409, USADepartment of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, 400 W. 13th St., Rolla, MO 65409, USAWe numerically investigate the dynamics of a pair of circular Janus microparticles immersed in a Newtonian fluid under a simple shear flow and a uniform magnetic field by direct numerical simulation. Using the COMSOL software, we applied the finite element method, based on an arbitrary Lagrangian-Eulerian approach, and analyzed the dynamics of two anisotropic particles (i.e., one-half is paramagnetic, and the other is non-magnetic) due to the center-to-center distance, magnetic field strength, initial particle orientation, and configuration. This article considers two configurations: the LR-configuration (magnetic material is on the left side of the first particle and on the right side of the second particle) and the RL-configuration (magnetic material is on the right side of the first particle and on the left side of the second particle). For both configurations, a critical orientation determines if the particles either attract (below the critical) or repel (above the critical) under a uniform magnetic field. How well the particles form a chain depends on the comparison between the viscous and magnetic forces. For long particle distances, the viscous force separates the particles, and the magnetic force causes them to repel as the particle orientation increases above the configuration’s critical value. As the initial distance decreases, a chain formation is possible at a steady orientation, but is more feasible for the RL-configuration than the LR-configuration under the same circumstances.https://www.mdpi.com/2312-7481/7/1/16Janus particlesLR-/RL-configurationuniform magnetic fieldsimple shearchain formationdirect numerical simulation |
| spellingShingle | Christopher Sobecki Jie Zhang Cheng Wang Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow Magnetochemistry Janus particles LR-/RL-configuration uniform magnetic field simple shear chain formation direct numerical simulation |
| title | Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow |
| title_full | Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow |
| title_fullStr | Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow |
| title_full_unstemmed | Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow |
| title_short | Dynamics of a Pair of Paramagnetic Janus Particles under a Uniform Magnetic Field and Simple Shear Flow |
| title_sort | dynamics of a pair of paramagnetic janus particles under a uniform magnetic field and simple shear flow |
| topic | Janus particles LR-/RL-configuration uniform magnetic field simple shear chain formation direct numerical simulation |
| url | https://www.mdpi.com/2312-7481/7/1/16 |
| work_keys_str_mv | AT christophersobecki dynamicsofapairofparamagneticjanusparticlesunderauniformmagneticfieldandsimpleshearflow AT jiezhang dynamicsofapairofparamagneticjanusparticlesunderauniformmagneticfieldandsimpleshearflow AT chengwang dynamicsofapairofparamagneticjanusparticlesunderauniformmagneticfieldandsimpleshearflow |