磁流变液阻尼托辊的设计与优化

Design and Optimization of a Magnetorheological Fluid Braking Roller

针对带式输送机在下运过程中易超速甚至失速的问题,设计了一种与传统无阻尼托辊结构相契合的多级线圈磁流变阻尼托辊,该阻尼托辊将多个线圈并联内置于静止导磁环内,显著增强了磁流变液阻尼间隙内磁场的强度及均匀性。首先,对磁流变阻尼托辊的磁路进行了理论分析,推导了其阻尼力矩模型,其次,研究了励磁线圈个数、输送机带速对输出阻尼力矩的影响,最后利用遗传算法对其进行了优化,确定了其最佳的几何结构参数。研究结果表明:磁流变阻尼托辊最佳的励磁线圈个数为5个,此时其能输出的阻尼力矩值达到最大,而输送机带速对输出阻尼力矩几乎没有影响;优化后,其输出阻尼力矩提升了约21.7%。研究结果可以为带式输送机的制动提供参考。

Aim at the problem that the belt conveyor is easy to overspeed or even stall in the process of downloading,a multi-coil magnetorheological braking roller(MRBR)agreeing with the traditional undamped roller structure is designed.Multiple coils are paralleled and placed in a static magnetic conduction ring which greatly enhances the strength and uniformity of the magnetic field in the MRF damper gap.Firstly,the magnetic circuit of the MRBR was analyzed theoretically,and its damper moment model was deduced.And than,the influence of the number of excitation coils and the belt speed of conveyor on the output damping moment were studied.Finally,the optimal geometric parameters were determined by genetic algorithm.The results show that the optimum number of excitation coils for the MRBR is five,and the maximum value of the damper moment can be obtained at this time.And the belt conveyor speed has litter effect on output damping moment.Compared with before optimization,the output damping moment increased by about 21.7%.The results can provide reference for the braking of the belt conveyor.