The Particle Motion Rule Analysis And The Optimum Structure Parameter Determination Of The New Vertical Shaft Impact Crusher Based On EDEM

Vertical shaft impact crusher is widely used in the medium and fine crushing of iron ore.Poor crushing effect on fine particles has become a bottleneck restricting the performance improvement of this kind of crusher.Therefore,how to improve the performance of vertical shaft impact crusher becomes an important research topic.Further research on this subject is of great significance for enriching the design ideas of vertical shaft crusher and improving the performance of this type of crusher.This paper focuses on solving the bottleneck problem that restricts the performance improvement of vertical shaft impact crusher.Based on pfl-600 crusher,a new structure assumption of reverse rotating double-rotor vertical shaft crusher is proposed,and the three-dimensional solid model and particle bond crushing model are established on the platform of three-dimensional design software SolidWorks and discrete element source software EDEM.Using the control single variable method,the motion trajectory of the material particles in the crushing chamber of the new vertical shaft crusher was measured by discrete element software EDEM.The effects of mineral particle diameter and lower rotor speed on particle motion in the crushing chamber were studied.Through the simulation analysis of the particle motion rule in the crushing chamber,it can be seen that the new vertical shaft crusher has a good effect on the acceleration of small-particle size particles,and the velocity of small-particle size particles fluctuates greatly.The new crusher has no obvious effect on the acceleration of large-size particles,but the velocity fluctuation of large-size materials is small and the speed is relatively stable.The variation of lower rotor speed has little effect on the maximum velocity and velocity fluctuation of particles.The research object is the new type reverse double-rotor vertical shaft crusher.The force of its lower rotor is analyzed,and three factors affecting the crushing performance of the new type crusher are determined: the speed of the lower rotor,the installation Angle of counterattack hammer,and the number of counterattack hammer.At the same time,through the force analysis of the lower rotor,the initial momentum expression of the material hitting the lower rotor plate hammer is obtained,which theoretically shows that the new crusher is better than the traditional crusher in crushing performance.With the EDEM discrete element analysis software,the orthogonal test principle is used to carry out the multi-factor orthogonal test for the above three influencing factors.Through the regression analysis of the 18 groups of test results obtained from the orthogonal test,the main and secondary factors affecting the crushing performance of the new crusher were obtained as follows: the number of striking board hammers,the lower rotor speed,and the mounting Angle of striking board hammers.Through the analysis of the factors effect curve to get the optimal level of the three factors,determine the optimal structure parameters combination of a new type of crusher is: under the counter plate hammer installation Angle of the optimal level of between 5 °,15 °,and give preference to 10 °;The optimum number of counterblow hammer is 5.The new crusher and the traditional crusher were selected as the comparative research object,and the crushing performance was analyzed by EDEM software.Taking the number of bond fractures as the standard to measure the degree of mineral fragmentation,the curve of the number of bond fractures of mineral particles over time was obtained.Through the analysis of the curve,it can be seen that the new crusher has better crushing performance and the crushing efficiency is improved by 13% compared with the traditional crusher.The simulation results are consistent with the theoretical analysis results.The research results of this paper have high reference value and theoretical significance for promoting the structural innovation of vertical shaft impact crusher and improving the comprehensive performance of crushing equipment.