微小型燃气轮机燃烧室模化方法适用性的数值研究  

Numerical Study on Applicability of Modeling Methods for Micro Gas Turbine Combustion Chamber

作　　者：沈思远 宗超[1] 季晨振 朱彤[1] SHEN Si-yuan;ZONG Chao;JI Chen-zhen;ZHU Tong(School of Mechanical Kngineering and Energy,Tongji University,Shanghai,China,Post Code:201804)

机构地区：[1]同济大学机械与能源工程学院,上海201804

出　　处：《热能动力工程》2021年第8期56-64,共9页Journal of Engineering for Thermal Energy and Power

基　　金：上海市科学技术委员会科研计划课题(18DZ1202003);中央高校基本科研业务费(20120200417)。

摘　　要：为获得经济性好且准确性高的微小型燃气轮机燃烧室模化实验方法,采用简化的二维模型对不同模化准则、不同模化空气温度和不同燃料控制策略的模型分别进行数值模拟研究,并与设计状态进行对比。研究表明:对于燃料为甲烷的微小型燃气轮机燃烧室,随着压力指数n增大,混合气在燃烧反应区的停留时间增加,回流区面积减小;n选取1.75-2.0时能获得较为准确的污染物排放的模化效果;n=1,即采用等容积流率准则时,能获得较为准确的出口温度分布和流场相关的模化结果;采用等燃烧效率L准则,模化状态理论燃烧温度保持不变,空气温度从493 K降低至300 K时,反应区平均温度和停留时间变化不大,NOx体积分数升高10×10^(-6),燃烧效率降低了0.5%,燃烧不充分,CO体积分数大幅升高。In order to obtain one kind of economical and accurate modeling experimental method of micro gas turbine(MGT)combustion chamber,the numerical simulation researches on various modeling criteria,air temperatures and fuel control strategies were respectively performed based on a simplified 2 D model,comparing with the design condition.The research results show that for the MGT combustion chamber with the fuel of methane,the standing time of fuel mixture across the combustion reaction zone increases and the recirculation zone reduces as the pressure index n increases.The modeling effects of the pollutant emission are more accurate with n between 1.75 and 2.0.The modeling results of outlet temperature distribution and flow field structure can be obtained more exactly when n is 1,that is when adopting equal volume flow rate criterion.Through adopting equal combustion efficiency L criterion,when the theoretical combustion temperature remains changeless under modeling state and the air temperature decreases from 493 K to 300 K,the average temperature and standing time of reaction zone change slightly,NOx emission increases by 10 ppm and the combustion efficiency is reduced by 0.5%,resulted in the great enhancement of CO emission with insufficient combustion.When carrying out the low-pressure modeling experiment of MGT combustion chamber,a modeling method using L criterion with modeling air temperature at room temperature can be adopted to achieve more accurate modeling results of pollutant emission more economically,the NOx emission can be obtained through the temperature control strategy and the equivalent ratio control strategy is suitable for measuring CO emission.

关 键 词：微燃机燃烧室 低压模化准则 压力指数 数值模拟 

分 类 号：TK471[动力工程及工程热物理—动力机械及工程]