摘 要：为研究燃气热水锅炉炉内动力场的稳定性，采用计算流体力学软件Fluent中的标准k-ɛ湍流模型分析15%、27%、48%和100%负荷4种工况下的炉内压力、速度和烟气流动特性。研究表明：燃气炉内烟气流动较为复杂，存在明显的流动不畅区域，涡流较多，烟气流动阻力较大，其中换热管区域压降比λ约52%；负荷变化时，应尽量减少出口负压，不应高于-400 Pa；换热管入口截面烟气速度存在较大差异， Vmax/Vmin 约为3~7，且随负荷增长而增大。

Abstract:To study the stability of the aerodynamic field inside a gasfired hot water boiler,the standard k-ɛ turbulent flow model in the CFD software Fluent was used to analyze the pressure,speed and flue gas flow characteristics in the boiler at 15%,27%,48% and 100% of the rated load,totaling four operating conditions.It has been found that the flue gas flow in the boiler will be relatively complex,existing conspicuously poor flow zones,having relatively more vortexes and a relatively big flue gas flow resistance.Among them,the pressure drop ratio ? in the heat exchange tube zones will be around 52%.When the load varies,more efforts should be made as possible to reduce the negative pressure at the outlet,not higher than -400 Pa.In addition,a relatively big difference will be present in the velocities of the flue gases in the cross section at the inlet of the heat exchange tubes,Vmax/Vmin being about 3 to 7 and will increase with an increase of the load.

TK224.1

吉林省科技发展计划(20140204049SF)