结构参数对平焰燃烧器流场的影响

Influence of structure parameter on flow field in flat flame burner

针对现有的天然气平焰燃烧器,采用RNGk-ε湍流模型和EDM燃烧模型,运用计算流体力学软件和建模工具对天然气平焰燃烧器流场进行了数值模拟,并应用五孔探针等工具对天然气平焰燃烧器冷态流场进行了测试,模拟结果分析表明：燃料径向喷出、空气进口偏心距l/D为0.476、烧嘴砖曲率半径R/D为1.14~1.71、旋流数S为0.61~1.68、混合距离L/D为0.6~0.9时能获得较佳的燃烧效果（其中,D为燃烧器喷口直径）。通过分析比较模拟结果和试验结果,发现两者的分布规律基本一致,数据基本吻合,回流区和主流区基本相同,并且与理论分析一致,符合实际情况,说明了天然气平焰燃烧器流场数值模拟结果是真实可信的,可为天然气平焰燃烧器的工业应用提供重要参考依据,也为天然气平焰燃烧器的设计、研究提供了有效的研究方法和途径。

Flow field of natural gas flat flame burner was simulated by CFD software and modeling tool with RNG k-ε model and EDM model.The experiment for testing the cold flow field of a natural gas flat flame burner was accomplished using the equipment just as five hole probe.The results show that characteristic parameter of excellent combustion effect is that the form of the fuel eject is radial,the eccentricity distance of the air inlet（l/D） is 0.476,the curvature radius of the burner brick（R/D） is 1.14～1.71,the swirling number（S） is 0.61～1.68,and the mixture distance（L/D） is 0.6～0.9（D is the diameter of the burner throat）.Based on the comparisons of the simulation results and the experiment,it is discovered that the distribution rule of flow field which accords with theoretical analysis is similar to practical situation,and main flow zone and recirculation zone are uniform.Therefore,it is indicated that numerical simulation of natural gas flat flame burner is authentic.This supplies an important reference and a warrant for industrial application of natural gas flat flame burner,and offers an economical and effective means for the study and the improvement of natural gas flat flame burner.