采用欧拉-拉格朗日方法，建立了湿法烟气脱硫系统折流板除雾器内气液两相流动模型。通过三维数值模拟，得到了不同进口气速和叶片间距下液滴的运动和捕集特性，分析了液滴间的碰撞作用、气流对液滴的破碎作用以及液滴与壁面间的相互作用对分离效率的影响规律。结果表明：进口气速和液滴粒径是影响分离效率的主要因素，小粒径液滴对气流的跟随性较强，大粒径液滴的运动主要由惯性主导；模拟中考虑液滴的碰撞作用时整体的除雾效率增大，气流对液滴的破碎作用对分离效率的影响甚微，考虑了液滴与壁面间相互作用的模型可更加准确地描述分离过程中出现的二次夹带现象。

The EulerLagrange approach was adopted to establish the gasliquid twophase flow in baffle demister of the wet flue gas desulfurization system.Threedimensional numerical simulation was established to investigate the particle motion and trapping characteristics which were calculated under various inlet gas velocities and plate spacing,then the effects of collision between droplets,the breakup of droplets by gas flow and the interaction between droplets and wall film on separation efficiency were analyzed,respectively.The simulation results showed that inlet gas velocity and droplet size are the main factors that affect the separation efficiency.The small size droplets have strong followability to the main gas flow,while the movement of large size droplets is mainly dominated by inertia.In addition,the overall demisting efficiency is increased when the collision of droplets is considered.The effects of droplet breakup on separation efficiency is minimal,and the model that considers the interaction between the droplet and the wall film can more accurately describe the secondary entrainment that occurs during the separation process.

X701.3

国家重点研发计划专项（2018YFB0905205-05）；教育部重点实验室开放课题（szjj2017-089）；西华大学项目（xjjg2017083）