刮板输送机上散料流形成及重载段链环力学特性分析

Analysis of granular flow formation and contact force s characteristics of load chain of scraper conveyor

针对复杂工况下刮板链的载荷多变问题,对刮板输送机上煤散料的运动及链环的受力特性进行了分析。首先,基于离散元法和多体动力学法,建立了刮板输送机的刚散耦合模型;然后,对其输送过程中刮板输送机上散料流的形成及煤散料堆积轮廓的成因进行了分析,并以此为基础进一步研究了重载段链环的运行阻力和动载荷;最后,基于理论分析和仿真运行的结果,对平稳、紧急停机及满载启动工况下,输送机刮板链环间接触力的大小和变化趋势,及主要影响因素进行了分析。研究结果表明:输送机平稳运行时,因散料堆积而导致的挡煤板侧链环间的接触力更大,其值为0.328 kN~122.557 kN;紧急停机时,输送机运行速度的降低使得其接触力值减小为0.745 kN~77.602 kN;满载启动时,因启动速度增大和煤散料堆积使得接触力值异常增大,且最大值为161.328 kN;该结果可以为解决实际工况中刮板链的卡链或断链提供理论依据。

Aiming at the problem of variable load of scraper chain under complex working conditions,the movement of coal granular on scraper conveyor and the stress characteristics of chain link were analyzed.Based on the discrete element method and multi-body dynamics method,a DEM-MBD(discrete element method and multi body dynamics)scraper conveyor model was established;based on the analysis of the formation of granular flow and coal granular accumulation profile on scraper conveyor,the running resistance and dynamic load of chain link in heavy haul section were further studied;finally,based on the analysis of theoretical analysis and simulation results,the size,variation trend and main influencing factors of contact force of scraper chain link under stable,emergency shutdown and full load start-up conditions were explored.The results show that the contact force between the chain links on the side of the coal baffle is greater due to the accumulation of coal granular under the stable condition,and its value is 0.328 kN~122.557 kN;under the emergency shutdown condition,the contact force decreases to 0.745 kN~77.602 kN due to the decrease of scraper chain speed;under the condition of full load start-up,and not at the moment of start-up,the contact force value increases abnormally due to the increase of starting speed and the accumulation of coal granular,and the maximum value is 161.328 kN.The research results provide a theoretical basis for solving chain sticking or chain breaking of scraper chain under actual working conditions.