可燃气阵列驻涡强化混合模型及其应用

发布时间：2018-01-09 05:08

本文关键词：可燃气阵列驻涡强化混合模型及其应用　出处：《中国科学院研究生院(工程热物理研究所)》2016年博士论文　论文类型：学位论文

【摘要】：为了拓展稀预混燃烧技术在高温升燃烧室、含氢燃料燃烧室和航改燃气轮机紧凑型燃烧室中的应用,本文提出了适用于可燃气的阵列驻涡强化混合模型：以特殊形状的扰流子构造流形可控的阵列驻涡流动,在强化气流输运与掺混的同时有效抑制回火和挂火。本文分析了阵列驻涡模型的流动特征、燃料-空气混合性能、抗挂火机理和声学性能。结果表明,阵列驻涡流形稳定,回流区尺寸与流动雷诺数弱相关；混合机制包括剪切拉伸、漩涡搅拌和湍流输运,两级叶片阵列可将混合气的混合不均匀度指标降低至入口处的0.8%以下；内部的燃烧反应具有亚临界稳定性特征,存在抗挂火工作状态,对于预热温度在300～700K、当量比在0.55～1.0范围内的甲烷-空气预混气,其抗挂火临界邓克尔数约为2.23；消声能力强,在典型燃烧室压力脉动峰值频段,两级叶片阵列的声传递损失比等长直管段高出20dB以上。基于二维阵列驻涡流动,通过展向积叠的方式,本文提出了燃气轮机阵列驻涡预混喷嘴设计,研究了单元预混喷嘴的工作性能。结果表明,相比于常规旋流式预混喷嘴,阵列驻涡预混喷嘴在轴向长度缩短三分之一的情况下,将出口混合不均匀度指标降低了一半；预混燃烧实验中,阵列驻涡预混喷嘴工作安全稳定,同时兼容含氢燃料和甲烷,具有不低于3.0的预混燃烧工况调节比,对含氢量小于60%的燃料,在烟气温度1700K的工况下,氮氧化物排放量低于50mg/Nm.(@15％O2).基于阵列驻涡预混喷嘴,本文在燃烧室中对阵列驻涡预混燃烧技术开展了压力模化试验。结果表明,阵列驻涡预混技术与燃气轮机燃烧室的结构和控制策略适应性良好；各个预混喷嘴下游的火焰稳定,各燃烧模态间的调整顺利；烟气温度在1400～1615K范围内,采用全预混燃烧模态,燃烧室氮氧化物排放量不高于47mg/Nm.(@15％O2)；火焰筒内压力脉动峰值不高于进气总压的0.42%,燃烧噪声得到了有效抑制。
[Abstract]:In order to expand the application of lean premixed combustion technology in high-temperature combustion chamber, hydrogen-containing fuel combustion chamber and air-modified gas turbine compact combustion chamber. In this paper, an array standing vortex-enhanced hybrid model suitable for gas is proposed: the controllable array standing eddy current is constructed by using a special shape scrambler. The flow characteristics of the array Vortex model, the fuel-air mixing performance, the anti-fire mechanism and the acoustic performance are analyzed. The array has stable standing vortex shape, and the size of the reflux region is weakly correlated with the flow Reynolds number. The mixing mechanism includes shear stretching, swirl stirring and turbulent transport, and the two-stage blade array can reduce the mixture unevenness index to less than 0.8% of the inlet. The internal combustion reaction has the characteristic of subcritical stability and has the working state of anti-hanging fire. For the preheating temperature of 300 ~ 700K, the equivalent ratio of methane to air is in the range of 0.55 ~ 1.0. The critical Dunkel number is about 2.23; The sound transfer loss of the two stage blade array is more than 20 dB higher than that of the equal length straight tube in the peak frequency range of the pressure pulsation in the typical combustion chamber. Based on the standing eddy current of the two-dimensional array, the method of spanned stacking is adopted. In this paper, the design of gas turbine array standing vortex premixing nozzle is presented, and the performance of the unit premixed nozzle is studied. The results show that compared with the conventional swirl premixing nozzle. When the axial length of the array Vortex premixing nozzle is reduced by 1/3, the mixing evenness index of the outlet is reduced by half. In the premixed combustion experiment, the array Vortex premixing nozzle works safely and stably, and it is compatible with hydrogen fuel and methane at the same time, and has a premixed combustion condition adjustment ratio of not less than 3. 0 for the fuel with hydrogen content less than 60%. At the flue gas temperature of 1700 K, the nitrogen oxide emissions are less than 50 mg / N 路m 路m 路m 路L ~ (15) O ~ (2 +) and are based on the array Vortex premixed nozzles. In this paper, the pressure modeling test of the array Vortex premixing technology is carried out in the combustion chamber. The results show that the array Vortex premixing technology has a good adaptability to the structure and control strategy of the gas turbine combustor. The flame downstream of each premixed nozzle is stable and the combustion modes are adjusted smoothly. The flue gas temperature is in the range of 1 400 ~ 1615K and the combustion mode is fully premixed. The nitrogen oxide emission from the combustion chamber is not higher than 47 mg / Nm 路L ~ (-1) O _ (2) O _ (2). The peak value of pressure pulsation in the flame tube is not higher than 0.42% of the total inlet pressure, and the combustion noise is effectively suppressed.
【学位授予单位】：中国科学院研究生院(工程热物理研究所)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TK473

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