【作者】 郭菁；

【导师】 孙保民；

【作者基本信息】 华北电力大学（北京） ， 热能工程， 2003， 硕士

【摘要】 煤粉锅炉是火力发电厂的重要设备之一，它的安全性和经济性对生产十分重要。提高锅炉效率、减少超温爆管、降低污染物的排放等对国民经济的发展有重要意义。而这些都必须深入详细地研究炉膛内煤粉的燃烧过程及其产生的温度场、速度场等。而在过去几十年中，煤粉燃烧技术的发展主要是基于电厂锅炉运行所积累的经验及一些小规模试验装置所测得的数据，这些经验和数据会局限燃烧技术的应用。随着电子计算机技术的不断发展，燃烧过程的数值模拟已经成为燃烧理论研究和燃烧装置设计的重要手段，它能够详细地模拟炉内燃烧所产生的温度场、速度场，压力场以及各种组分的分布和污染物的产生等。本文以太原第二热电厂四期扩建200MW机组7#炉为研究对象，在CFD软件FLUENT原有燃烧综合模型的基础上，通过该软件提供的用户接口函数udf，对其中的挥发份析出模型进行了改进，采用了比较先进的活化能分布模型即DAEM模型，再对7#炉的燃烧过程和污染物的生成进行数值模拟。得出了炉内C(S)、CH4、NO等组分的分布，从而指导实际锅炉运行及进行污染物的控制。本文深入讨论了国内外对煤粉燃烧各个过程所采用的子模型，比较其优缺点。在计算时，不仅考虑了采用模型的先进性，而且还考虑了各个子模型之间的相互协调及一个合理的计算时间的问题。更多还原

【Abstract】 Boiler is one of the main equipments in the power plant, and it’s security and economy are very important. To increase the efficiency of the boiler, decrease the occurring of the blowout of the pipes, and reduce the let of the pollutant and so on, we need to analysis the process of the combustion of pulverized coal in the boiler and it’s temperature distributions, pressure distribution, velocity, and so forth.However, development of coal combustion technology in the past was largely empirical in nature, being based primarily on years of accumulated experience in operations of utility furnaces and on data obtained from sub-scale test facilities. Empirically based experience and data have limited applicability. With the fast development of computer, the numerical simulation of combustion has been a important means of the combustion theory research and combustion device design, and can accurately predict the temperature distributions, gas composition, velocity, NOx formation and so on. In this paper, by using the user defined functions of the CFD software FLUENT, I introduced the more advanced devolatilization model DAEM into the software instead of the original devolatilization models. So on the basis of the other submodels of the comprehensive combustion models in the software, the numerical simulation of the process of the combustion pulverized coal and the formation of NOx of the seventh boiler of the 200MW set of the Tai Yuan Second Thermal Power Plant is done, and the distribution of C(S), CH4 and NO can be seen, and this will help the control of pollutant and running of the boiler.The submodels used in the process of the pulverized coal combustion are discussed in this paper,. a comprehensive model must balance submodels sophistication with computational practicality. In other words, a<WP=5>comprehensive model must incorporate submodels that not only simulate the phenomena of interest, but do so in a way that can be coupled with the other submodels and solved in a reasonable amount of time.更多还原