位移钝体稳燃的旋流预混燃烧污染物生成特性

doi:10.16085/j.issn.1000-6613.2021-2366

摘要/Abstract

摘要：

石化炉、加热炉等设备中燃烧过程的污染物控制具有重要意义。旋流预混燃烧过程具有低NO _x 排放的潜力，引发了学术界和工业界的广泛关注。结合钝体燃烧和旋流燃烧各自的优势，本文设计了带有位移钝体的旋流预混燃烧器。首先研究了不同钝体结构下的污染物的生成情况，确定了最优的钝体结构，在此基础上进一步研究了在不同旋流数下污染物生成、火焰形态和温度场分布情况。研究发现，钝体角度为30°、体积较小的倒锥形钝体具有较低的NO _x 和CO生成量。NO _x 生成量随着旋流数从0增加到0.83呈先减小后增加的趋势，并且当旋流数为0.25时，NO _x 生成量最低。在同一热功率下，火焰高度随着旋流数的增加而减小。在同一旋流数下，火焰宽度随热功率增大呈增大趋势。NO _x 生成量变化规律与其火焰温度分布规律一致，即NO _x 生成量最低的工况下火焰温度也比较低。由此推测旋流引发的温度变化是NO _x 生成量变化的主要影响因素之一。本文的研究结论对旋流预混燃烧器的设计提供了理论基础。

关键词: 贫燃预混燃烧, 钝体, 旋流燃烧, 氮氧化物, 温度场

Abstract:

The emission control of the combustion process in petrochemical and heating furnaces is of a great significance. Swirl combustion has the potential of low NO _x emission, attracting wide attention from both academia and industry. Combining the advantages of bluff body combustion and swirl combustion, a swirl premixed burner integrated with a displacing bluff body is proposed in this study. The structure of the displacing bluff body was first optimized based on the investigation into the emission under different bluff body structures. Subsequently, the studies on emission, flame morphology, and temperature distribution were conducted. The results showed that the smaller inverted cone-shaped bluff body with the half-cone angle of 30° provided relatively lower NO _x and CO emissions. The NO _x emission first decreased and then increased as the swirl number increased from 0 to 0.83, with the NO _x emission being the lowest when the swirl number was 0.25. At the same thermal power of the combustion, the flame height decreased as the swirl number increased. At the same swirl number, the flame width increased as the thermal power increased. The trend of NO _x emission variation was consistent with that of temperature. The lower NO _x emission was, the lower temperature of the corresponding flame would be. Thereby, it is expected that the temperature change caused by the swirl number variation is one of the main reason for the NO _x emission variation. The conclusion of present study provides a theoretical basis for the design of swirl premixed burner.

Key words: lean premixed combustion, bluff body, swirl combustion, nitrogen oxides, temperature field

中图分类号:

TK16

韩徳琳, 李丹, 王天天, 张海, 张扬, 王随林. 位移钝体稳燃的旋流预混燃烧污染物生成特性[J]. 化工进展, 2022, 41(6): 2915-2923.

HAN Delin, LI Dan, WANG Tiantian, ZHANG Hai, ZHANG Yang, WANG Suilin. Emission characteristics of swirl premixed combustion stabilized using a displacing bluff body[J]. Chemical Industry and Engineering Progress, 2022, 41(6): 2915-2923.

图/表 11

图1 燃烧器结构示意图

表1 旋流器角度与旋流数对照表

角度α	旋流数S
0°	0
10°	0.12
20°	0.25
30°	0.4
40°	0.59
50°	0.83

图2 实验原理图及实物图

表2 仪器测量误差表

物理量	仪器名称	量程	误差
$Q C H 4$	音速喷嘴+压力表	0~2MPa	±0.25%量程
Q_air	质量流量计	0~200L/min	±1%量程
T	B型热电偶	800~1700^oC	±0.5%
O₂质量分数		0~21％	0.1％
NO浓度	ECOM-J2KN	0~4000μL/L	±2%测量值
NO₂浓度	烟气分析仪	0~500μL/L	±2%测量值
CO浓度		0~4000μL/L	±2%测量值

表2 仪器测量误差表

物理量	仪器名称	量程	误差
$Q C H 4$	音速喷嘴+压力表	0~2MPa	±0.25%量程
Q_air	质量流量计	0~200L/min	±1%量程
T	B型热电偶	800~1700^oC	±0.5%
O₂质量分数		0~21％	0.1％
NO浓度	ECOM-J2KN	0~4000μL/L	±2%测量值
NO₂浓度	烟气分析仪	0~500μL/L	±2%测量值
CO浓度		0~4000μL/L	±2%测量值

图3 不同燃烧热功率下喷嘴角度对NO x 和CO排放量的影响

图4 不同钝体形状大小图

图5 钝体形状对NO x 排放量的影响

图6 旋流数对火焰形状的影响

图7 旋流数对NO x 排放量的影响

图8 温度随轴向距离变化图

图9 不同高度处，温度随径向距离的变化

参考文献 23

1	DUTKA Marcin, DITARANTO Mario, Terese LØVÅS. NO _x Emissions and turbulent flow field in a partially premixed bluff body burner with CH₄ and H₂ fuels[J]. International Journal of Hydrogen Energy, 2016, 41(28): 12397-12410.
2	BEHZADI Milad, SIYADAT Seyed Hamzeh, OMMI Fathollah, et al. Study of the effect of bluff body size on stability limits of a premixed natural gas swirl burner[J]. Journal of Thermal Analysis and Calorimetry, 2022, 147(2): 1583-1596.
3	周力行, 陈兴隆, 张健. 旋流数对湍流燃烧中NO生成影响的研究[J]. 工程热物理学报, 2002, 23(5): 637-640.
	ZHOU Lixing, CHEN Xinglong, ZHANG Jian. Studies on the effect of swirl on no formation in turbulent combustion[J]. Journal of Engineering Thermophysics, 2002, 23(5): 637-640.
4	赵黛青, 杨浩林, 杨卫斌. 旋流对同轴富氧扩散燃烧NO _x 排放的影响[J]. 燃烧科学与技术, 2008, 14(5): 383-387.
	ZHAO Daiqing, YANG Haolin, YANG Weibin. Effects of swirl on NO _x emission in coflow oxygen-enriched laminar diffusion flames[J]. Journal of Combustion Science and Technology, 2008, 14(5): 383-387.
5	NAHVI Morteza, PARSAFAR Mohammad Mahdi. Experimental analysis of blockage effect on low-swirl burner combustion parameters for lean premixed natural gas-air flames[C] //Proceedings of 18th Fluid Dynamics Conference. Mashhad, Iran, 2019.
6	JOHNSON M R, LITTLEJOHN D, NAZEER W A, et al. A comparison of the flowfields and emissions of high-swirl injectors and low-swirl injectors for lean premixed gas turbines[J]. Proceedings of the Combustion Institute, 2005, 30(2): 2867-2874.
7	SYRED Nicholas. 40 Years with swirl, vortex, cyclonic flows, and combustion[C]//49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition. Orlando, Florida. Reston, Virginia: AIAA, 2011: 105.
8	LITTLEJOHN D, CHENG R K. Fuel effects on a low-swirl injector for lean premixed gas turbines[J]. Proceedings of the Combustion Institute, 2007, 31(2): 3155-3162.
9	邢双喜. 微小型燃气轮机径向旋流预混燃烧特性研究[D]. 北京: 中国科学院研究生院(工程热物理研究所), 2012.
	XING Shuangxi. Investigation on premixed combustion characteristics with radial-swirler in micro gas turbine[D]. Beijing: Institute of Physics, Chinese Academy of Sciences (Institute of Engineering Thermophysics), 2012.
10	YELLUGARI Kranthi, GOMEZ Rodrigo Villalva, GUTMARK Ephraim J. Effects of swirl number and central rod on flow in lean premixed swirl combustor[C]//AIAA Scitech 2020 Forum. Orlando, FL. Reston, Virginia: AIAA, 2020: 0433.
11	FU Zaiguo, GAO Huanhuan, ZENG Zhuoxiong, et al. Generation characteristics of thermal NO _x in a double-swirler annular combustor under various inlet conditions[J]. Energy, 2020, 200: 117487.
12	ZHAO Tiezheng, LIU Xiao, ZHANG Zhihao, et al. The effects of swirl number on the combustion characteristics in an internally-staged combustor[J]. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 2022, 236(6): 3230-3244.
13	石黎, 付忠广, 王瑞欣, 等. 旋流数对燃烧不稳定性及NO _x 生成的影响[J]. 动力工程学报, 2017, 37(9): 691-698.
	SHI Li, FU Zhongguang, WANG Ruixin, et al. Effects of swirl number on combustion instability and NO _x formation of a gas turbine[J]. Journal of Chinese Society of Power Engineering, 2017, 37(9): 691-698.
14	YILMAZ Harun, Omer CAM, YILMAZ Ilker. Swirler geometry effects (dh/do ratio) on synthetic gas flames: Part 1: Combustion and emission characteristics[J]. Energetika, 2021, 67(1/2): 48-54.
15	BEER J M, CHIGIER N A. Combustion aerodynamics[M]. London : Applied Science Publishers Ltd, 1972.
16	中华人民共和国环境保护部, 国家质量监督检验检疫总局. 锅炉大气污染物排放标准: [S]. 北京: 中国环境科学出版社, 2014.
	Ministry of Environmental Protection of the People’s Republic of China, General Administration of Quality Supervision, Inspection and Quarantine of the People’s Republic of China. Emission standard of air pollutants for boiler: [S]. Beijing: China Environment Science Press, 2014.
17	MOFFAT Robert J. Describing the uncertainties in experimental results[J]. Experimental Thermal and Fluid Science, 1988, 1(1): 3-17.
18	DEGENEVE A, JOURDAINE P, MIRAT C, et al. Effects of a diverging cup on swirl number, flow pattern and topology of premixed flames[J]. Journal of Engineering for Gas Turbines and Power, 2019, 141(3): 031022.
19	李鹏飞. 气体燃料MILD燃烧的实验和模拟研究[D]. 北京: 北京大学, 2013.
	LI Pengfei. Experimental and numerical investigation of the mild combustion of gaseous fuels in a laboratory-scale furnace [D]. Beijing: Peking University, 2013.
20	EVANS M J, MEDWELL P R, WU H, et al. Classification and lift-off height prediction of non-premixed MILD and autoignitive flames[J]. Proceedings of the Combustion Institute, 2017, 36(3): 4297-4304.
21	BOVINA T A. Studies of exchange between re-circulation zone behind the flame-holder and outer flow[J]. Symposium (International) on Combustion, 1958, 7(1): 692-696.
22	吕崇德. 热工参数测量与处理[M]. 2版. 北京: 清华大学出版社, 2001.
	Chongde LYU. Thermal parameter measurement and processing[M]. 2nd ed. Beijing: Tsinghua University Press, 2001.
23	PETERSON R C, LAURENDEAU N M. The emittance of yttrium-beryllium oxide thermocouple coating[J]. Combustion and Flame, 1985, 60(3): 279-284.

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