燃料分配方式对微燃机燃烧室燃烧性能影响

提出了一种喷口位置可变采用燃料多点喷射的干式低排放(DLE)微型燃气轮机燃烧室,为了获得值班级与主燃级之间燃料分配方式对燃烧性能的影响,对该燃烧室在不同分配方式下的燃烧性能进行了实验测试与数值模拟。结果表明:燃料喷口位置改变对污染物排放影响不显著;燃料分配方式的改变对温度场和污染物的生成特性有影响,随着两级燃料分配比例的增大,NOx排放量呈现先减少后增加的趋势,存在一个最佳的燃料分配比例使NOx排放最低;燃烧室内存在明显的中心回流区(PRZ),便于点火及火焰传播;热力型NOx的生成量与温度高于1 950 K的区域大小和最高燃气温度有直接关系。所设计的燃烧室在以天然气为燃料的所有工况下NOx排放都可降低到50 mg/m3以下,达到了低污染燃烧室排放标准(小于50 mg/m3)。

Effect of fuel distribution on combustion performance for micro gas turbine combustor,

A dry low emission (DLE) micro gas turbine combustor with variable nozzle position and multi-point fuel injection was put forward. In order to gain the effect of different fuel-staged methods on the combustion performance for the combustor, and the effect of fuel distribution mode between pilot and primary on combustion performance, different distribution modes of the combustor were experimentally studied by numerical simulation. Results showed that: the change of fuel nozzle position had little effect on the emissions. With the increase of two-stage fuel distribution ratio, the NOx emissions decreased first and then increased, and there existed an optimal fuel distribution ratio to minimize NOx emissions. There existed obviously a primary recirculation zone (PRZ) in combustor, helping to facilitate ignition and propagation of flame. The amount of thermal NOx produced was directly related to the size of the region above 1 950 K and the highest gas temperature. The NOx emissions of the designed combustion can be reduced to below 50 mg/m3 under all working conditions with natural gas as fuel, which can reach the level of low-emission combustion (less than 50 mg/m3).