中文摘要：

采用数值方法分析了值班燃料比对某重型燃气轮机环形燃烧室内热力型NO_x生成的影响规律,分析表明：在一定范围内调整值班燃料比,控制燃烧室内温度及高温区分布,是降低NO_x排放的有效手段。增大值班燃料比使得值班扩散火焰温度升高,有利于燃料气流的着火与稳定燃烧,但也导致中轴线附近区域热力型NO_x生成速率升高。增大值班燃料比使得预混燃料化学当量比减小,壁面附近区域火焰温度降低、高温区范围减小,热力型NO_x生成速率降低。因此,存在最佳值班燃料比使得该重型燃机NO_x排放最低。值班火焰采用扩散燃烧方式,继续增大值班燃料比则将导致NO_x排放浓度迅速升高。

英文摘要：

The computational fluid dynamics（CFD） method was employed to simulate the impact of pilot fuel percentage on NOx formation characteristic in a heavy duty gas turbine annular combustion chamber. The predicted results show that proper adjusting pilot fuel percentage to control peak temperature and region with high temperature is an effective mean to decrease the emission of NOx in combustion chamber. Increase of pilot fuel percentage to improve the temperature of pilot diffusion flame is beneficial for ignition and stable combustion of premixed fuel gas. However, thermal NOxformation rate relatively rises with increasing of pilot fuel percentage in the region near central axis of the combustion chamber. The stoichiometric ratio in premixed stream decreases with the increasing of pilot fuel percentage which compress the premixed flame temperature and the formation of thermal NOxnear the back flow region after the boss. There exists an optimal pilot fuel percentage to minimum NOx emission for this heavy duty gas turbine. Further increasing pilot fuel percentage will greatly improve the emission of NOx due to the diffusion combustion mode of pilot flame.