燃煤电站爆米花灰颗粒可能严重威胁SCR(选择性催化还原）系统催化剂的性能，建立CFD（计算流体力学）模型，优化爆米花灰分离捕集方案是预防爆米花灰危害催化剂的必要手段。为模拟爆米花灰颗粒的流动特性，实验测定、计算了不同粒度大小共90个颗粒的尺寸、密度、阻力系数和球度等空气动力学参数，并拟合得到了阻力系数比与球度的β-Ψ近似关系曲线。实验和计算结果表明，爆米花灰颗粒表观密度随粒度的增大而增大，且与颗粒内部孔隙率大小关系密切，平均表观密度约1 182 kg/m3。颗粒平均阻力系数0.765，平均球度0.66；随着颗粒粒度的减小，颗粒的球化程度逐渐增大，平均阻力系数有所减小。

The performance of the SCR system catalyst of coal-fired power plant may deteriorate due to popcorn ash particles.Establishing CFD model to optimize the schemes of separating and trapping popcorn ash particles is a necessary measure to prevent catalyst from being threatened by popcorn ash particles. To simulate the popcorn ash particles flow characteristics,90 particles with different granularities were studied and corresponding aerodynamic parameters such as size,density,terminal velocity,drag coefficient,sphericity,etc.,were measured experimentally and calculated.The approximate relation curve between drag coefficient ratio and sphericity β-Ψ was fitted. Experimental and calculation results showed that,the apparent density of popcorn ash particles increases with the increase of particle granularity,and the average apparent density is found to be 1 182 kg/m3,which closely relates to the internal porosity size.The particle average drag coefficient is 0.765 and the calculated average sphericity is 0.66. Spheroidization degree of particles tends to be high and the average drag coefficient value decreases with the decrease of the particle granularity.

TK227.1