形状对大倾角煤层飞矸运移的影响

Influence of shape on flying gangue migration in steeply dipping coal seam

大倾角煤层工作面飞矸运移过程具有一定的复杂性和随机性,准确模拟飞矸运移过程对大倾角煤层的安全高效开采具有重要的意义。以山西某大倾角特厚煤层矿井为研究背景,根据球度设计涵盖所有椭球形飞矸形状的数值模拟试验方案,采用能量跟踪法对飞矸在三维工作面回采空间的运移过程进行数值模拟试验,得到飞矸的运动轨迹,以及任意时刻的速度、角速度和能量变化曲线,分析了形状对飞矸运移过程的影响。并考虑了多飞矸同时运移时碰撞对飞矸运移过程的影响,模拟对比飞矸之间无碰撞和有碰撞时的运移过程。为验证本文方法的准确性和可行性,采用Rockyfor3D软件模拟的轨迹进行对比。结果表明:本文方法模拟的轨迹与Rockyfor3D软件模拟的轨迹基本吻合,且飞矸与工作面底板的碰撞接触点更加明显。飞矸的运移主要受飞矸形状、飞矸与工作面底板的碰撞的影响较大。此外,飞矸在运移过程中发生的相互碰撞会导致飞矸运动轨迹发生改变,侧向偏移距离增加,导致飞矸在运移过程中与煤壁和支架立柱、刮板机等设备发生碰撞,增加飞矸防护难度。将能量跟踪法应用于现场,可为飞矸灾害的预测与防护提供借鉴。

The migration process of flying gangue has certain complexity and randomness in the working face of steeply dipping coal seam,so the accurate simulation of the migration process of flying gangue has important theoretical and practical significance for the safe and efficient mining in steep seam.Taking a large inclination thick coal seam in Shanxi coal mine as the research background,according to the spherical design,a numerical simulation test scheme covering all ellipsoidal flying gangue shapes was designed.A numerical simulation test was carried out on the migration process of flying gangue in the working space of 3D working face by using the energy tracking method,the trajectories of flying gangue can be obtained,and at any time of the curves of velocity,angular velocity and energy,and the influence of shape on the migration process of flying gangue was analyzed.The influence of the collision on the migration process of flying gangue was considered,and the migration process of the flying gangue without collision and with collision was simulated and compared.In order to verify the accuracy and feasibility of this method,the trajectories simulated by Rockyfor3D software were compared.The results show that the trajectory simulated by the method in this paper is basically consistent with the trajectory simulated by Rockyfor3D software,and the collision contact point between flying gangue and the floor of working face is more obvious.The migration of flying gangue is mainly affected by the shape of flying gangue,and the collision between flying gangue and the floor of the working face.In addition,the collision of flying gangue in the process of migration will cause the trajectory of flying gangue to change and the lateral migration distance to increase,resulting in the collision of flying gangue with coal wall,support column,scraper and other equipment in the process of migration,which will increase the difficulty of the protection of flying gangue.Applying the energy tracking method to the site can provide a certain theoretical basis for the prediction and protection of flying gangue hazards.