船舶主机SCR脱硝CFD流场模拟及设计优化

CFD Flow Field Simulation and Design Optimization of the SCR Denitration for a Ship’s Main Engine

基于某船舶主机SCR脱硝系统采用CFD方法进行流场模拟研究及结构优化设计。首先,通过在烟道和反应器内设置导流板和气流分布板,优化系统结构。其次,分别研究了液滴雾化平均粒径D和喷射角度α对催化剂入口氨浓度的影响,结果表明:液滴平均粒径越小和喷射角度越大,液滴的停留时间越短。最后,研究了静态混合器对氨浓度分布的影响,结果显示:静态混合器能够显著提高氨与烟气的混合效率,平均值为60.2%。

Based on a ship’s main engine SCR denitration system,a CFD method is used to conduct flow field simulation research and structural optimization design.Firstly,the system structure is optimized by arranging baffles and gas distribution plates in the flue and reactor.Secondly,the effects of droplet atomization average particle size D and spray angle α on the ammonia concentration at the catalyst inlet were studied respectively.The results show that the smaller the droplet average particle size and the larger the spray angle,the shorter the droplet residence time.Finally,the effect of the static mixer on ammonia concentration distribution was studied,and the results show that the static mixer could significantly improve the mixing efficiency of ammonia and flue gas,with an average value of 60.2%.