磁性矿粒动态磁化模拟及精确磁力计算

Dynamic Magnetization Simulation and Accurate Magnetic Force Calculation of Magnetic Mineral Particles

针对现有微磁模拟软件无法直接计算磁力、宏观磁场下磁性矿粒所受磁力计算不精确以及动态磁化过程不明等问题,利用微磁学理论和数值模拟技术对现有的磁性矿粒磁力计算方式进行改进,结合多物理仿真软件COMSOL的物理场开发器、APP开发器以及磁场无电流物理场设计了一种计算磁性矿粒精确受力的软件。详细说明了磁性矿粒微磁模拟软件的原理,并将该软件与微磁学专业软件MERRILL在自发磁化状态下进行对比,最后比较传统仿真磁力计算方法和微磁学磁力计算方法在均匀磁场下计算100 nm不规则磁铁矿颗粒磁力的准确性。研究结果表明:以相同的网格大小5 nm对80 nm的立方体磁性矿粒进行模拟,2种软件呈现的不同初始状态的自发磁化状态一致;使用磁滞回线展现了正八面体磁性矿粒在变化磁场中的动态磁化过程;在均匀磁场下,采用微磁学的磁力计算方法相较于传统计算方法计算精度由10-3数量级提高至10-11数量级;该软件为从微磁学角度进行磁选理论研究提供了一个有力的工具,进一步促进了磁性矿粒在磁选过程中的动态磁化过程研究,对于提高磁性矿粒的磁力计算精度具有重要意义。

Addressing the issues of existing micromagnetic simulation software′s inability to directly calculate magnetic forces,the inaccuracy of magnetic force calculations on magnetic particles under macroscopic magnetic fields,and the unclear depiction of dynamic magnetization processes,this study employs micromagnetic theory and numerical simulation technology to refine the calculation methods for magnetic forces on magnetic particles.In collaboration with the multi-physics simulation software COMSOL,a software tool has been developed utilizing its physical field developer,app developer,and a magnetic field without electric current for precise force calculation on magnetic particles.This paper elaborates on the principles of the micromagnetic simulation software for magnetic particles and compares it with the professional software MERRILL in the state of spontaneous magnetization.It concludes with a comparison of the accuracy between traditional simulation methods and micromagnetic force calculation methods for determining the magnetic force on irregular magnetic particles of 100 nm under a uniform magnetic field.The research findings indicate that,when simulating cubic magnetic particles of 80 nm with an identical grid size of 5 nm,both pieces of software show consistent spontaneous magnetization states across different initial conditions.The dynamic magnetization process of octahedral magnetic particles in a changing magnetic field is demonstrated using hysteresis loops.Under a uniform magnetic field,the magnetic force calculation method using micromagnetism improves the calculation accuracy from 10-3 orders of magnitude to 10-11 orders of magnitude compared to the conventional calculation method;The software serves as a powerful tool for advancing the study of magnetic separation theory from a micromagnetic perspective,further facilitating the investigation of the dynamic magnetization process of magnetic particles during magnetic separation.This contributes significantly to enhancing the accuracy of calculating the magnetic force of magnetic particles.