双级反向旋流器气量分配的不同将影响旋流强度和回流区大小，进而改变燃料/空气混合均匀度，最终影响燃烧室NO〖HT5”〗x排放和贫熄特性。为确定最佳的空气分配方案，针对某种新型设有文丘里管式预混合段的双级轴向反旋旋流器，实验研究了两级旋流器气量分配对燃烧室氮氧化物排放、热态流场以及贫熄特性的影响。实验结果表明：最优气量分配方案为内旋空气流量比外旋空气流量等于1/0.67的方案。相对于此比值等于1/1.38的基准方案，最优方案在高功率和低功率情况下，可分别降低NO〖HT5”〗x排放9.4%和18.5%，NO〖HT5”〗x排放量分别为39.5和33.4 mg/m3；此外，最优方案的熄火边界最宽，在本文研究范围内其熄火当量比几乎低至零。

The variation of air split of dualstage counter rotating swirlers will have an effect on swirl strength and recirculation zone size.It will further change the mixing uniformity of fuel and air,and finally makes a difference to the NO〖HT5〗x emissions and the lean blowout limits.In order to determine the best scheme of air flow distribution,the effects of airflow split between two swirlers on the NO〖HT5〗x emissions,thermal flow fields and the lean blowout limits were studied experimentally with dualaxial counter rotating swirlers equipped with venturi pipe type premixing section.The experimental results showed that the optimal scheme should be that the air flow ratio of the inner swirler to the outer swirler should be1/0.67.Compared to the baseline with the ratio of 1/1.38,the optimized scheme can reduce the NO〖HT5〗x emissions by 9.4% and 18.5%,respectively,with the value being 39.5 mg/m3and 33.4 mg/m3,under the high and low power conditions.In addition,the lean blowout limit of the optimized scheme is the widest and its LBO (lean blowout) equivalence ratio could be as low as close to zero within the range of study.

V231.2

国家自然科学基金（91441131，91441119）