摘要
为改善余热锅炉入口流场均匀性,应用三维CFD计算模型,对某台燃气轮机余热锅炉的过渡烟道进行了结构优化数值模拟,对烟道长度、前上仰角段长度、后部水平段长度和前上仰角角度4个结构参数进行了优化设计,并针对其优化效果的不足提出了一种新型过渡烟道(S型引导扩散烟道)。结果表明:原烟道长度与烟道底面倾斜角有关,影响气流扩散剧烈性;前上仰角角度决定气流在前上仰角段的扩散趋势;前上仰角段长度关系到气流扩散的充分性;后部水平段长度对气流扩散无明显影响;参数优化未改变在烟道底部形成一股高速主气流的弊端,需对烟道结构进行改进;新型(S型引导扩散)过渡烟道将气流引导至相对余热锅炉入口中心的位置后进行双向扩散,回流区和高速区减小,明显改善流场均匀性,具有广阔的研究前景。
In order to improve the flow field uniformity of Heat Recovery Steam Generator （HRSG） inlet, numerical simulation was carried out to optimize the transition flue structure of a Gas Turbine HRSG using three-dimensional CFD model. Four parameters of flue duct structure, including flue length, front elevation angle, front elevation length and horizontal section length, were optimized, and a new transition flue duct （S type flue duct） was put forward to overcome some deficiencies which remained even after the structural optimization. Results showed that for traditional flue duct, flue length, which related to the inclination of flue bottom face, affected flow diffusion severity; front elevation angle determined flow diffusion tendeney; front elevation length influenced diffusion adequacy and that rear horizontal section length had no obvious effect on flow field. After structure parameters optimization, a main high-speed flow was still formed at the bottom of the flue duct, so the traditional flue duct structure required a modification using a new transition flue duct. The new transition flue duct （S type flue duct） directs gas to the area relative to the center position of HRSG inlet, and then flow spread in two directions. Recirculation zone is reduced as well as high-speed zone, and velocity distribution is much more uniform. S type flue duct has a broad research prospect for its obvious ability in improving the flow field uniformity.
出处
《锅炉技术》
北大核心
2015年第4期12-17,共6页
Boiler Technology
关键词
余热锅炉
过渡烟道
数值模拟
流场均匀性
结构优化
Heat Recovery Steam Generator
transition flue duct
numerical simulation
flow field uniformity
structural optimization
