匀强磁场作用下磁性和非磁性混合湿颗粒运动行为的研究

Study on the Movement Behavior of the Magnetic and Non-Magnetic Mixed Wet Particles in Uniform Magnetic Field

通过数值模拟研究外加均匀磁场作用下磁性和非磁性混合湿颗粒的运动行为.数值模拟中,采用离散元法(DEM)追踪颗粒运动,并考虑磁场力和液桥力对颗粒运动行为的影响.通过比较无外加磁场下二维干颗粒溃坝问题数值模拟结果和实验结果,验证了数学模型的有效性.针对二维干颗粒溃坝问题,数值模拟了外加磁场下五种不同磁颗粒体积分数(0,25%,50%,75%,100%)的湿颗粒的运动.数值结果显示:随着磁颗粒体积分数的增加,颗粒平均速度和平均运动距离降低,颗粒的聚集行为增强,聚集行为增强的具体表现为颗粒链状结构增多.

In this paper,numerical simulation is performed to study the magnetic and non-magnetic mixed wet particles movement under external uniform magnetic field.The discrete element method(DEM)is adopted to solve the movement of particles,and in the numerical simulation,both magnetic force and liquidbridge force are taken into account.Firstly,the model is validated by comparing the present numerical results with the existed experimental results of two-dimension(2D)dam-break problem.Furthermore,the movements of particles in 2D dam-break problem with five different magnetic particles ratios(0,25%,50%,75%and 100%)are simulated.Numerical results show that the particles get lower velocity and displacement with higher magnetic particles ratio,and more magnetic particle chains appear when the magnetic particles ratio goes to higher.