【摘要】 运用流体动力学软件Fluent6.3对自行设计的燃气燃烧器的燃烧性能进行了数值模拟研究,分析了不同外圈助燃空气和中心辅助空气配比条件下炉膛内的速度场、温度场以及NOX的生成情况,并对试验结果进行了验证。结果表明,采用适当的外圈助燃空气和中心辅助空气比例,该旋流燃烧器的燃烧性能稳定,燃料燃烧完全,烟气中可燃成分比例不超过0.06%(600ppm);炉膛内温度分布相对均匀,炉内气体温度偏差不超过30℃,满足高效燃烧的要求;烟气中NOX的含量平均不超过0.006%(60ppm),远远低于国家排放标准,可以很好控制燃烧产物对大气的污染。随着外圈助燃空气和中心辅助空气的比例增大,炉膛最高温度和平均温度降低,NOX生成量降低,加入空气总量增大,系统的热效率有所降低,但燃烧器产生的高温高速气流,强化了炉内的对流传热,可提高炉子生产率。更多还原

【Abstract】 The combustion performances of a self-designed gas fired burner were studied numerically with the Computational Fluid Dynamics simulation software Fluent 6.3.The velocity and temperature fields and the formation of NOX under different ratio of the outer combustion supporting air flow and the core auxiliary air flow were analyzed.The experiment results were verified.The results show that with proper ratio of the outer and the core air flow the performance of the burner is stable and the fuel burns perfectly and the content of inflammable composition is below 600 ppm in the exhaust gas.The furnace temperature is relatively uniform.The temperature deviation of the furnace atmosphere is not more than 30 ℃,which can meet the requirement of high efficient combustion.The NOX of the exhaust gas is below 60 ppm in average,which is lower than that of the national standard so as to have better combustion pollution control.With the ratio of the outer and the core air increases,the highest and the average furnace temperature decrease,and NOX formation volume is declined.With the total air quantity increases,the thermal efficiency of the system is reduced.However,the efficiency of convective heat transfer of the furnace is strengthened by high-speed gas flow spraying from burner with high temperature,which can increase the productivity of the furnace.更多还原