中心分级燃烧室贫油熄火试验研究与数值模拟

Experimental Study and Numerical Simulation of Lean Blow-Out of Centrally-Staged Combustor

关键词:  燃烧室  贫油熄火  旋流器  旋向组合  叶片角度

摘要:

为研究三级旋流器下中心分级燃烧室贫油熄火性能，常压下针对在不同进气速度以及旋流器几何参数下中心分级燃烧室贫油熄火特性进行了试验研究与数值模拟，获得了在一定条件下的贫油熄火规律。试验结果表明：随着进气速度增大到35m/s时,贫油熄火油气比减小至0.0070,说明进气速度对贫油熄火起重要作用;值班级旋向相反时贫油熄火油气比(A方案为0.0066，B方案为0.0071)均小于同向时(C方案为0.0078，D方案为0.0074)，且A方案最小，说明值班级旋向对贫油熄火性能有明显的影响，值班级反向时熄火特性最好，且主燃级旋向对其作用不大，最佳旋向组合为A方案，即值班级1，2级叶片旋向反向，值班级2级叶片与主燃级叶片旋向相同；值班级1，2级叶片角度增大贫油熄火油气比分别下降了将近4%和9%，其熄火特性变好。数值模拟计算结果与试验结果熄火规律变化一致。

Abstract:

In order to study lean blow-out(LBO) performance of centrally-staged combustor with three-stage swirler, the LBO characteristics of the centrally-staged combustor under different inlet airflow velocity and swirler parameters of the swirler were experimentally studied and numerically simulated at atmospheric pressure, and the LBO rules under certain conditions was obtained. The test results showed that: With the increase of the inlet airflow velocity to 35m/s, the lean blow out fuel-air-ratio (θ_lbo) decreases to 0.0070, which indicates that it plays an important role in LBO performance. Theθ_lbo in reverse rotation of pilot stage (Case A is 0.0066, and the Case B is 0.0071) is less than the same rotation (Case C is 0.0078, and Case D is 0.0074), and the Case A is the smallest. It shows that the pilot stage rotation has a significant effect on the LBO performance. The LBO characteristic is the best when the pilot stage is reversed, and the primary stage rotation has little effect on it. The best combination of rotational direction is Case A, that is, the rotational direction of stage 1 and stage 2 blades in pilot is reversed, and the rotational direction of stage 2 blades in pilot is the same as that of primary stage blades. With the increase of blade angle of stage 1 and stage 2 in pilot stage, theθ_lbo decreased by nearly 4% and 9%, respectively, and the LBO characteristics became better. The numerical simulation rules are consistent with the experimental rules.