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基于离散元方法,建立了二维扁平熔化气化炉的离散元模型,应用此模型从颗粒尺度对物料运动流型、速度场以及空隙度分布进行了研究。结果表明:采用加入示踪颗粒的方法,对颗粒运动流型进行分析,示踪颗粒层逐渐由直线型变为两侧向下弯曲型;从物料速度场分布可以看出,炉内存在死料柱区、活塞流区以及管道流区等运动区域。回旋区对炉内竖直方向速度分布的影响限于距炉缸底部上方0.18m处,回旋区半径的减小导致炉内颗粒活跃区域缩小,死料柱区高度增加;炉内物料运动存在一定的偏析现象,该现象也可从空隙度分布看出。炉内死料柱区空隙度为0.37左右,回旋区处为0.65左右,位于自由空间下方和死料柱区以及回旋区之间的活塞流区空隙度在0.37~0.65之间。
Based on the discrete element method, a discrete element model of a two-dimensional flat melter-gasifier was established. The flow pattern, velocity field and porosity distribution of the material were studied from the particle size scale using this model. The results show that the particle flow pattern is analyzed by the method of adding tracer particles, and the particle layer gradually changes from straight line to downward bending pattern. From the distribution of material velocity field, it can be seen that there are dead material in the furnace Column area, plug flow area and pipe flow area and other sports area. The influence of the convolution zone on the vertical velocity distribution in the furnace is limited to 0.18 m above the bottom of the hearth. The decrease of the radius of the convolution zone leads to the reduction of the active area of the particles in the furnace and the increase of the dead zone height. Segregation phenomenon, the phenomenon can also be seen from the distribution of porosity. The void fraction in the dead column in the furnace is about 0.37 and that in the convolution zone is about 0.65. The void fraction in the plug flow area below the free space and between the dead-material column area and the raceway is between 0.37 and 0.65.