Tangentially fired furnaces are vortex-combustion burners preferably used for oxy-fuel combustion in order to minimize the CO₂ emission and control the boiler temperature. The objective of the present study is to investigate numerically the combustion and emission characteristics of oxy-fuel combustion of turbulent reacting flows in a three-dimensional model furnace of a 600 MW tangentially fired boiler. Numerical calculations of the flow field and thermal fields as well as the species concentrations for the oxy-fuel combustion in the furnace of a gaseous fuel tangentially fired boiler were conducted. Three cases of oxy-fuel combustion were investigated. These were 73%, 79%, and 65% of volumetric inlet CO₂ while the remaining inlet volume was O₂. The results of these three oxy-fuel cases are compared to the air-fired combustion. In the present model, the radiation heat transfer was solved by the weighted sum gray gases approach, whereas the chemical reaction model was facilitated by a simple lumped reaction model. The results show that the oxy-fuel case of 79% CO₂ can preferably minimize the combustion temperature for highly sustainable materials. However, the 65% CO₂ oxy-fuel case generates high temperature values for improving the heat characteristics. The 73% CO₂ oxy-fuel and the air-fired cases are fairly close to each other in thermal behavior.

中文翻译：

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600 MW切向燃烧的气态燃料锅炉中的含氧燃料燃烧

切向燃烧炉是涡流燃烧炉，优选用于氧燃料燃烧，以最大程度地减少CO ₂排放并控制锅炉温度。本研究的目的是对600 MW切向燃烧锅炉的三维模型炉中湍流反应流的含氧燃料燃烧的燃烧和排放特性进行数值研究。进行了气体燃料切向燃烧锅炉的炉内流场和热场以及含氧燃料燃烧的物种浓度的数值计算。调查了3种含氧燃料燃烧的情况。它们分别是入口体积CO _2的73％，79％和65％，而其余入口体积为O ₂。将这三种含氧燃料箱的结果与空气燃烧进行了比较。在本模型中，辐射热传递是通过加权和灰气体方法解决的，而化学反应模型是通过简单的集总反应模型来促进的。结果表明，对于高度可持续的材料，在含氧量为79％的CO _2的情况下，最好将燃烧温度降至最低。然而，在65％CO _2的含氧燃料的情况下，产生用于改善热特性的高温值。73％的CO ₂含氧燃料和空燃箱的热行为非常接近。