The radiant tube burner was modeled and analyzed by the numerical simulation method to investigate the influence factors and rules of NO_(x) emissions in a W-type radiant tube.These factors,which include air preheatin...The radiant tube burner was modeled and analyzed by the numerical simulation method to investigate the influence factors and rules of NO_(x) emissions in a W-type radiant tube.These factors,which include air preheating temperature,excess air coefficient,and fuel gas composition,were modified to study their effects on NO_(x) emissions under varying working conditions.Simulation results were compared with the theoretical calculation value based on chemical reaction equilibrium theory and the onsite experimental value to verify the simulation accuracy.The results show that NO_(x) emissions rise with increasing air preheating temperatures.NO_(x) production increases to an extreme value and then decreases during the oxygen-poor to oxygen-enriched process with the rise of the excess air coefficient.Enhancing the proportion of coke oven gas in the fuel gas raises the combustion temperature as well as the NO_(x) discharge.Both the thermal efficiency and NO_(x) emissions should be balanced.Therefore,the recommended values based on the simulation results are as follows:the air preheating temperature should not exceed 400℃,the excess air coefficient should be between 1.1 and 1.2,and the volume fraction of the coke oven gas should not exceed 30%.展开更多
以功率为100 k W的双P型辐射管为研究对象,利用Fluent软件对其内部的流动、燃烧及传热过程进行模拟,并对比了在有回流和无回流状况下辐射管的气相温度场及壁面温度变化情况,证明在有回流状况下,辐射管内部燃烧状态处于"无焰燃烧&qu...以功率为100 k W的双P型辐射管为研究对象,利用Fluent软件对其内部的流动、燃烧及传热过程进行模拟,并对比了在有回流和无回流状况下辐射管的气相温度场及壁面温度变化情况,证明在有回流状况下,辐射管内部燃烧状态处于"无焰燃烧"状态。对六种不同空气、烟气喷口排布方式的方案进行了模拟,对比了其燃烧最高温度、烟气温度、管壁温度以及烟气中三原子分子浓度的差异。并以管壁温度和辐射管传热效率为判别依据,得到了较优的布置方案。展开更多
文摘The radiant tube burner was modeled and analyzed by the numerical simulation method to investigate the influence factors and rules of NO_(x) emissions in a W-type radiant tube.These factors,which include air preheating temperature,excess air coefficient,and fuel gas composition,were modified to study their effects on NO_(x) emissions under varying working conditions.Simulation results were compared with the theoretical calculation value based on chemical reaction equilibrium theory and the onsite experimental value to verify the simulation accuracy.The results show that NO_(x) emissions rise with increasing air preheating temperatures.NO_(x) production increases to an extreme value and then decreases during the oxygen-poor to oxygen-enriched process with the rise of the excess air coefficient.Enhancing the proportion of coke oven gas in the fuel gas raises the combustion temperature as well as the NO_(x) discharge.Both the thermal efficiency and NO_(x) emissions should be balanced.Therefore,the recommended values based on the simulation results are as follows:the air preheating temperature should not exceed 400℃,the excess air coefficient should be between 1.1 and 1.2,and the volume fraction of the coke oven gas should not exceed 30%.
文摘以功率为100 k W的双P型辐射管为研究对象,利用Fluent软件对其内部的流动、燃烧及传热过程进行模拟,并对比了在有回流和无回流状况下辐射管的气相温度场及壁面温度变化情况,证明在有回流状况下,辐射管内部燃烧状态处于"无焰燃烧"状态。对六种不同空气、烟气喷口排布方式的方案进行了模拟,对比了其燃烧最高温度、烟气温度、管壁温度以及烟气中三原子分子浓度的差异。并以管壁温度和辐射管传热效率为判别依据,得到了较优的布置方案。