永磁筒式磁选机磁系结构的优化设计方法研究

Study on structural optimization design of magnetic system of drum permanent magnetic separator

优化磁系结构设计是改善磁场特性、提高磁选机性能的有效途径。在研究永磁筒式磁选机磁场分布的基础上,提出结构优化设计方法。以磁感应强度、磁场波动系数、径向磁场梯度为性能指标,选择磁极宽度间隙比和宽度高度比作为优化参数,基于有限元仿真模型建立了参数与性能指标之间的函数关系;以磁场波动为优化目标,采用非线性约束优化的方法,获取最优参数值;以φ1 250 mm筒径磁选机为例进行仿真,结果表明,采用所提出的优化方法设计的磁选机性能指标优于传统方法设计的同类产品,且节省25%永磁材料。

Structural optimization design of the magnetic system is an effective way to improve the characteristics of the magnetic field and the performance of the magnetic separator. After studying the distribution of the magnetic field of the drum permanent magnetic separator, the paper offered the structural optimization design method. In the method, the magnetic induction intensity, the fluctuation coefficient of the magnetic field and the radial gradient of the magnetic field were taken as the performance indexes, and the ratio of width to gap of magnetic poles as well as the ratio of their width to height were selected as the optimization parameters. And then, the paper established the functional relationship between the parameters and the performance indexes based on finite element model. In addition, it took the fluctuation of the magnetic field as the optimization objective, and applied nonlinear constraint optimization method to obtain the optimal parameter values. Finally, the simulation results of a φ 1 250 mm magnetic separator showed： the performance indexes of the magnetic separator designed by the proposed method was superior to that by traditional design method, and 25% of permanent magnetic material was saved.