基于CFD-DEM的旋风除尘器内气固流动特性研究

为了研究旋风除尘器内气固流动特性，采用CFD-DEM耦合算法研究不同入口气体速度下旋风除尘器内颗粒流态、静压、径向速度及轴向速度分布特征。结果表明:煤屑颗粒在离心力和径向曳力的作用下以螺旋颗粒条带靠近除尘器的壁面稳定向下移动，随着入口风速的增加煤屑颗粒条带变宽，条带与除尘器的第1次接触的拐点上移，螺距减小；除尘器内部压力轴向变化较小，径向变化较大，随着入口气体速度增加，除尘器壁面附近高压区范围和压力也随之增加，除尘器上方和下方的负压区变宽并朝轴向方向延伸；随入口气体速度增加，除尘器内径向速度和轴向速度逐渐增加，煤屑颗粒在除尘器中部聚集较多，煤屑停留时间变长，入口气体速度为15 m/s时，煤屑颗粒在除尘器内停留时间最长。

Study on gas solid flow characteristics of cyclone dust collector based on CFD-DEM

In order to study the gas solid flow characteristics of cyclone dust collector,the distribution characteristics of particle flow pattern,static pressure,radial velocity and axial velocity in the cyclone dust collector under different inlet gas velocities were studied by using the CFD-DEM coupling algorithm.The results showed that the coal cuttings particles moved downward stably near the wall of cyclone dust collector with the pattern of spiral particle strip under the effect of centrifugal force and radial drag force.With the increase of inlet gas velocity,the coal cuttings particles strip became wider,the inflection point of the first contact between the strip and the dust collector moved upward,and the pitch decreased.The axial change of internal pressure in the dust collector was small,while the radial change was relatively large.With the increase of inlet gas velocity,the range and pressure of the high pressure zone near the wall of dust collector increased also,and the negative pressure zone above and below the dust collector became wider and extended towards the axial direction.With the increase of inlet gas velocity,the radial velocity and axial velocity in the dust collector increased gradually,the coal cuttings particles gathered more at the middle of dust collector,and the residence time of coal cuttings became longer.When the inlet gas velocity was 15 m/s,the residence time of coal cuttings particles in the dust collector was the longest.