抗磁性物质的磁悬浮仿真及密度测量

Magnetic levitation simulation and density measurement for diamagnetic materials

利用COMSOL、Fluent和EDEM软件,仿真预测出不同磁悬浮装置下样品密度与悬浮高度之间的函数关系.在理论分析磁悬浮检测装置与原理的基础上,采用COMSOL软件模拟装置的磁场分布,通过拟合得到中心线上磁场强度表达式,并利用Fluent与EDEM软件耦合预测样品的悬浮高度.通过不同密度、不同磁铁间距的磁悬浮分组实验,验证数值仿真结果的正确性.实验结果表明,当磁铁间距为45mm时,样品密度与悬浮高度呈线性关系,测量偏差为-0.001 5~0.013 0g/cm^3;当磁铁间距为60mm时,样品密度与悬浮高度服从多项式函数关系,测量偏差达到-0.006 4~0.013 0g/cm^3.该数值仿真方法使用方便且密度检测精度高.

COMSOL,Fluent and EDEM software were combined to simulate the mathematic relationship between the density and the levitation height of diamagnetic materials under different levitation devices.Based on theoretical analysis of magnetic levitation device and its principle,COMSOL software was adopted to simulate the levitation devices' magnetic field,and the expression of the magnetic flux density on the center line was established by fitting.The materials' levitation height was predicted by the FluentEDEM software.Magnetic levitation experiments with various densities materials and different separation distances between two magnets were performed to verify the accuracy of simulation results.The experimental results show that,when the separation distance is 45 mm,there is a linear relationship between density and levitation height,and its density measurement deviation ranges from-0.001 5 g/cm^3 to 0.013 0 g/cm^3.When the separation distance is 60 mm,the relationship agrees with polynomial function,and the measurement deviation is from-0.006 4 g/cm^3 to 0.013 0 g/cm^3.The numerical simulation method is very convenient and has high accuracy in density measurement.