进风量对燃气燃烧器燃烧及NO_x排放特性影响

Influence of supply air rate on performance of gas burner and NO_x emission

运用Fluent软件对40 t/h锅炉用燃气燃烧器的性能进行三维数值模拟。首先用Pro/E软件画出燃气燃烧器和炉膛三维图,然后在Gambit中进行建模,采用相关数学模型,在Fluent中设置边界参数及初始条件,迭代计算得出结果。研究了燃烧器的总体性能,燃烧器及炉膛内部甲烷、空气、压力、温度分布云图。着重研究了进风量过大或过小时对燃烧器及炉膛内速度场、温度分布、NOx排放量的影响。结果表明:合适的进风量是保证燃烧器稳定燃烧的关键因素之一,对污染物NOx的排放也是关键的影响因素。数值的模拟计算结果对燃烧器优化设计改造提供了重要的研究依据。

The combustion performance of gas burner suitable for 40 t/h boiler were studied by three-dimensional numerical simulation software——Fluent.First,draw three-dimensional maps of the gas burner and furnace with the software of Pro/E,then with which to model in Gambit,set boundary parameters and initial conditions in Fluent,iteratively calculate three-dimensional simulation results.Research the overall performance of burner,involving burner and distribution maps of methane,air,pressure and temperature in internal furnace.Emphasize the influence of air supply on distribution maps.The results show that the appropriate supply air rate is one of the most important factors which maintain smooth combustion,also related to NOx emission.The numerical simulation results provides important basis for burner optimization.