| 159 | 0 | 180 |
| 下载次数 | 被引频次 | 阅读次数 |
为提高甲醇旋流燃烧器的燃烧效率,降低NO排放,通过数值模拟对甲醇旋流燃烧器的燃烧状态和NO排放进行了研究,并结合试验结果进行了对比和优化。通过激光粒度仪探究甲醇喷雾雾化效果和粒径分布特性,为数值模拟中甲醇液滴的离散相模型提供甲醇喷雾粒径参数,结果显示模拟喷雾粒径与试验高度吻合。重点分析了不同叶片角度下燃烧室内的速度分布、温度分布及NO质量浓度分布。研究结果表明:速度分布方面,随叶片角度增加,混合器的轴向速度受到抑制;叶片角度α=40°及α=60°时燃烧室内形成稳定回流区,显著改善甲醇与空气的混合效果。温度分布方面,小角度工况下高温区集中且温度较低,底部存在明显低温区;大角度工况下高温区范围扩大,温度显著提升,底部温度均匀性改善。燃烧效率随叶片角度增大而提高,但角度超过40°后提升效果减弱。燃烧室内及出口处NO生成质量浓度随叶片角度增大而升高。旋流器叶片角度对燃烧室内速度、温度、NO分布及燃烧效率均有显著影响,α=40°时在多方面表现较优。
Abstract:In order to improve the combustion efficiency of methanol swirl burners and reduce NO emissions,the combustion state and NO emissions of methanol swirl burners were investigated through numerical simulation. The results were compared and optimized with experimental data. A laser particle size analyzer was used to examine the atomization effect and droplet size distribution of methanol spray. This provided the spray size parameters for the discrete phase model of methanol droplets in the numerical simulation. The results show that the simulated spray size closely matches the experimental data. The study focuses on analyzing the effects of different blade angles on velocity distribution,temperature distribution,and NO mass concentration in the combustion chamber. The results indicate that as the blade angle increases,axial velocity of the gas mixture is suppressed. Stable recirculation zones are formed in the combustion chamber at blade angles of α = 40° andα = 60°,significantly improving the mixing of methanol and air. Regarding temperature distribution,under small blade angles,high-temperature zones are concentrated but relatively low in temperature,with noticeable low-temperature regions at the bottom. Under large blade angles,high-temperature zones expand,temperature increases significantly,and bottom temperature uniformity improves. Combustion efficiency improves as blade angle increases,but the improvement weakens when the angle exceeds 40°. NO generation concentration in the combustion chamber and at the outlet rises with increasing blade angles. The swirl vane angle significantly affects velocity,temperature,NO distribution,and combustion efficiency in the combustion chamber. The optimal performance is achieved at α = 40°.
[1] 傅学政,黄笃之,许朝晖,等.醇基燃料燃烧器技术进展概述[J].能源工程,2003(5):53-55.
[2] SUN Y Z,RAO Z M,ZHAO D,et al.Characterizing nonlinear dynamic features of self-sustained thermoacoustic oscillations in a premixed swirling combustor[J].Applied energy,2020,264:114698.
[3] 杨旸,李耀强,张金琦.基于数值方法的燃气轮机贫预混旋流燃烧室单头部结构设计[J].发电技术,2023,44(5):712-721.
[4] DAY M,TACHIBANA S,BELL J,et al.A combined computational and experimental characterization of lean premixed turbulent low swirl laboratory flames II.Hydrogen flames[J].Combustion and flame,2015,162(5):2148-2165.
[5] 杨晓晰.切缝旋流低NOx燃烧器流场温度场的实验与仿真研究[D].沈阳:东北大学,2018.
[6] POURHOSEINI S H,FAKHRI S,TAHERI E,et al.An Investigation on the effect of air swirler vane angle on liquid fuel combustion characteristics[J].Heat transfer-Asian research,2017,46(7):750-760.
[7] 周力行.旋流燃烧氮氧化物生成的研究进展[J].热能动力工程,2019,34(1):1-10,137.
[8] CHIONG M,VALERA-MEDINA A,CHONG W W F,et al.Effects of swirler vane angle on palm biodiesel/natural gas combustion in swirl-stabilised gas turbine combustor[J].Fuel,2020,277.
[9] HOU S S,LEE C Y,LIN T H.Efficiency and emissions of a new domestic gas burner with a swirling flame[J].Energy conversion and management,2007,48(5):1401-1410.
[10] 姜磊.低NOx双旋流燃气燃烧器流动及燃烧特性的实验研究[D].北京:中国科学院大学(中国科学院工程热物理研究所),2017.
[11] 米翠丽,樊孝华,魏刚,等.DRB-4Z型双调风旋流燃烧器出口流场的数值仿真研究[J].热力发电,2012,41(11):36-40.
[12] ZHEN H S,LEUNG C W,CHEUNG C S.Thermal and emission characteristics of a turbulent swirling inverse diffusion flame[J].International journal of heat and mass transfer,2009,53(5):902-909.
[13] ATEL V,SHAH R.Experimental investigation on flame appearance and emission characteristics of LPG inverse diffusion flame with swirl[J].Applied thermal engineering,2018,137377-137385.
[14] SYRED N,BEER J M.Combustion in swirling flows:a review[J].Journal of physics:conference series,2017,891(1):012237.
[15] LIU B,BAO B B,WANG Y H,et al.Numerical simulation of flow,combustion and NO emission of a fuel-staged industrial gas burner[J].Journal of the energy institute,2016,90(3):441-451.
[16] FAROKHI M,BIROUK M.A new EDC approach for modeling turbulence/chemistry interaction of the gas-phase of biomass combustion[J].Fuel,2018,220:420-436.
[17] 何悟,郑洪涛,蔡林,等.湍流燃烧模型在燃烧室数值计算中的对比分析[J].热科学与技术,2011,10(4):360-365.
[18] 杨自冬.低排温条件下混合器本体温度对SCR转化效率的影响[D].洛阳:河南科技大学,2023.
[19] LEFEBVRE A H,MCDONELL V G.Atomization and Sprays[M].Boca Raton,USA:CRC Press,2017.
[20] 谢俊,李俊楠,李润东.过量空气系数及旋流数对天然气燃烧特性的影响研究[J].热能动力工程,2024,39(4):114-121.
基本信息:
DOI:10.15926/j.cnki.issn1672-6871.2025.05.001
中图分类号:TQ038;TK16
引用信息:
[1]杜慧勇,任家毅,李可,等.基于CFD的工业炉甲醇燃烧器旋流火焰优化[J].河南科技大学学报(自然科学版),2025,46(05):1-9+117.DOI:10.15926/j.cnki.issn1672-6871.2025.05.001.
基金信息:
国家重点研发计划项目(2016YFD0700700)