基于回转输运试验的煤散料离散元接触参数修正

Modification of Discrete Element Contact Parameters of Coal Bulks Based on Rotary Transport Test

为获取精确的刮板输送机离散元模拟结果,基于回转输运试验,通过响应面法对煤料的接触参数进行修正.采用Plackett-Burman试验考察接触参数对受力及堆积角的影响,发现煤-钢静摩擦系数、煤-煤摩擦系数具有显著正效应.根据爬坡试验结果,以受力及堆积角为响应值规划Box-Behnken试验,建立受力、堆积角与显著项间的二次回归多项式,以实测数据为目标值求得最佳参数:煤-钢静摩擦系数为0.401,煤-煤静摩擦系数为0.333,煤-煤滚动摩擦系数为0.041.通过不同输运条件下的回转试验验证了参数的准确性,为刮板输送机的离散元研究提供参考.

To obtain the accurate discrete element simulation results of scraper conveyors,the contact parameters of coal bulks were corrected by the response surface method based on the rotary transport test.The Plackett-Burman test was used to investigate the effect of contact parameters on the force and stacking angles,and it was found that the static friction coefficient of coal-steel and the friction coefficient of coal-coal have significant positive effects.According to the results of the climbing test,the Box-Behnken test was planned with force and stacking angle as the response value,and the quadratic regression polynomials between forces,stacking angles and significant terms were established respectively.The optimal parameters were obtained with the measured data as the target value and the results showed that the static friction coefficient of coal-steel is 0.401,the static friction coefficient of coal-coal is 0.333,and the rolling friction coefficient of coal-coal is 0.041.The accuracy of the parameters was verified by the rotary test under different transportation conditions,which provides a reference for the discrete element study of scraper conveyors.