基于DEM的相近刃缘铲板切沙与受力过程分析

Analysis of Similar Blade Edge Sand Shovel on the Force and Sand Cutting Process Based on DEM

集沙铲是课题组研制的一款铁路轨道除沙车的重要工作部件。集沙铲在实际使用中受冲击大,铲板刃缘变形严重,这对集沙铲的使用是不利的。课题组拟在不影响抛沙效率的基础上,通过改变集沙铲的刃缘倾角降低集沙铲的受力值。论文建立了5种相近刃缘的集沙铲模型,通过离散元法与动力学耦合仿真,从颗粒微观形态分布和宏观集沙铲受力两个角度对改进效果进行了分析。通过分析颗粒的能量分布情况和铲板的受力发现,适当增加集沙铲的刃缘倾角,沙土颗粒的速度分布呈现均匀化分散的趋势,颗粒间能量分布更加均匀,铲板的工作受力得到较大改善。集沙试验表明,增加刃缘倾角不会影响集沙铲的抛沙效率。该研究过程证明了离散元与动力学耦合仿真方法用于集沙铲刃缘结构优化研究的可行性,同时有助于指导优化集沙铲的铲板刃缘结构。

The sand collecting shovel is an important part of the railway track sand removal vehicle.For the impact and severe edge deformation problems in practical application,its stress condition should be improved.In order to reduce the force of the sand shovel instead of affecting the sand throwing efficiency,the way of changing the edge shape of the sand collecting was taken.In this paper,5 sand shovel models with similar edges were established.By the coupling simulation of discrete element method and dynamics,the energy distribution of the particles was analyzed and the force of different sand shovels was obtained.The numerical simulation showed with an appropriate increase in the edge angle of the sand shovel,the velocity distribution of the sand particles was uniform and dispersed,the energy distribution between the particles was more uniform,and the working condition of the shovel was greatly improved.The bench test showed that the increased angle of the edge did not affect the sand throwing efficiency.The research process proved the feasibility of the discrete element method and dynamic coupling simulation method for the optimization of the edge structure of the sand shovel.The research results gave an optimization method for the blade edge structure of the sand shovels.