基于散体力学的大倾角螺旋输送机颗粒输送特性分析

Analysis on the particle transportation of the large-inclined screw conveyor based on the granule mechanics

针对大倾角螺旋输送机输送量估算不准确的问题,修正散体物料群角速度与输送角、螺旋轴角速度之间的函数关系,并通过研究不同转速和填充率下散体物料群自由表面曲线的表达式,推导出不同自由表面曲线下的散体物料群体积和输送量的计算公式。接着,通过具体的大倾角螺旋输送机模型验证文中提出的计算公式更符合实际值。其次,通过对物料在大倾角螺旋输送机中的受力和运动分析,给出散体物料向上输送的临界条件。找出螺旋输送机输送角与螺旋叶片升角之间的关系来避免'自锁'现象。最后考虑不同螺旋轴转速、填充率,运用离散元法仿真螺旋输送机的输送过程,得到大倾角螺旋输送机输送量和功率的变化趋势,为螺旋输送机的设计提出了合理的建议。

Currently,the transportation capacity of the large-inclined screw conveyor cannot be estimated in an accurate manner.Thus,in this article,the functional relation between the angular velocity of bulk material group and the angular velocity of helical shaft is corrected.By studying the expressions of the free surface curves of bulk material group under different rotational speeds and filling rates,the formulas of volume and transport of bulk material group under different free surface curves are derived.Then,the critical condition of upward transportation of bulk materials is verified through the specific model of the large-inclined screw conveyor.The relationship between the screw conveyor’s transportation angle and the angle of the spiral blade is found to prevent self-locking.Finally,both the rotating speed and the filling rate of different spiral shafts are taken into account.The change trends of the large-inclined screw conveyor’s transportation capacity and power are identified by means of the discrete element method,in order to simulate the transportation process.It provides reasonable advice for the design of screw conveyor.