微型燃气轮机燃烧室设计计算

Preliminary design of combustion chambers of micro gas turbines

燃烧室是燃气轮机的核心部件之一,其性能指标是衡量燃气轮机性能的重要依据。针对燃烧室的结构特点给出了微型燃气轮机燃烧室的综合设计方法:对燃烧室进行功能分区;依据CO和NOx的排放选择主燃区温度;根据经验值确定燃烧室内外筒直径;假设空气流量与气流温度沿轴线方向线性分布,通过计算空气滞留时间来选取燃烧室的长度;针对燃烧室壁面通气孔,先根据经验初步确定其在3个燃烧区域的大致分布,然后利用等效面积法进行具体设计。多次点火试验显示,采用该方法设计的燃烧室既没有熄火也没有火焰喷出,表明设计方法切实可行,实现了微型燃气轮机燃烧室的快速、准确设计。

The combustion chamber is one of the core components in a gas turbine,whose performance is an important index for evaluating the performance of the gas turbine.According to the structural characteristics of the combustion chamber,a comprehensive design method for it is given.Firstly,functional zoning was made on the combustion chamber.Then,the temperature of the main combustion zone was selected based on the emissions of CO and NOx,and the diameter of the outer cylinder was set in light of empirical values.Assuming that the air flow and the air temperature were linearly distributed along the axis,the length of combustion chamber could be chosen based on air residence time.To settle the vents down on the wall of the combustion chamber properly,the general distribution of the three combustion areas should be primarily set from experience and be specified by equivalent area method.Proven by several ignition tests,the combustion chamber designed by the method above has neither flameout nor flame ejection,which shows that the design method is feasible and realizes the rapid and accurate design of the micro gas turbine combustion chamber.