三次风对缝隙式W火焰锅炉炉内空气动力场的影响
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摘要
W型火焰锅炉具有炉膛温度高、火焰行程长等特点,适于燃烧无烟煤等低挥发分燃料。目前我国已投运的60余台W型火焰电站锅炉中,英国MBEL公司生产的W型火焰锅炉存在一些问题亟待解决,但目前国内对这方面的研究还很少。
本文针对某厂MBEL技术300MW缝隙式W型火焰锅炉炉内燃烧不稳定、灭火事故频繁、下炉膛结渣严重、煤粉气流着火较晚等问题,按照1:15的比例搭建了冷态模化试验台,通过改变底部三次风风量和角度安排实验工况,利用恒温热线风速仪系统对不同工况下炉内的流动状况进行测量实验。试验研究发现:现运行工况存在炉内气流所形成的W型形状前后拱方向不对称、贴壁气流冲刷水冷壁以及着火距离过长等问题。分析其原因为:MBEL技术的W型火焰锅炉具有下炉膛大、上炉膛小的特点,不能忽略折烟角对炉内流场的影响。通过在三次风喷口处加装导流板和改变三次风量及下倾角度可以解决原有工况存在的问题。加装导流板后随着三次风量的增加,炉内流场对称性变好,炉内结渣情况也得到好转,一二次风混合距离变短。但当三次风风量过大时,由于拱部气流量太小,射流刚性减弱,流场偏斜效果加剧。同时三次风风量过大容易引起冲刷冷灰斗等问题。
在研究三次风角度变化对炉内流场的影响时发现,随着三次风入射角度的减小,三次风对一二次风的向下引流作用变小,对炉内流场偏斜趋势的改善作用变小,同时,在炉内流场偏斜效果加剧时所能达到的最大三次风风量减小。
W-shaped flame boiler, with its own high-temperature and long-flame characteristics, is suitable for burning low volatile anthracite fuel. At present, there are more than 60 utility W-shaped flame boilers, and some of these of the MBEL company need to be resolved, but current research in this area rarely.
In this thesis, the aerodynamic fields in a 300MW W-shaped flame boiler`s furnace , which is designed by MBEL company, were studied on the single-phase cold model, which is built on the Similarity Theory in accordance with the ratio of 1:15 and an IFA300 constant-temperature anemometer system was used to measure the air velocity in the model. The experimental results reveals that there is a W-shaped flame in the furnace under the present work condition, but the W-shaped flame is asymmetric. This condition is improvement after the Air deflector is fixed. With the tertiary air increasing, the W-shaped flame Has become asymmetric and clinkering rate is diminution. but as the momentum of the tertiary air is decreased, the asymmetric W-shaped flame Become serious.
In the study of dip angle of the tertiary air we found that with the tertiary air reduced, its betterment of the asymmetric W-shaped flame is weaken and the flow field become asymmetric serious with a slight increase of the tertiary air.
本文针对某厂MBEL技术300MW缝隙式W型火焰锅炉炉内燃烧不稳定、灭火事故频繁、下炉膛结渣严重、煤粉气流着火较晚等问题,按照1:15的比例搭建了冷态模化试验台,通过改变底部三次风风量和角度安排实验工况,利用恒温热线风速仪系统对不同工况下炉内的流动状况进行测量实验。试验研究发现:现运行工况存在炉内气流所形成的W型形状前后拱方向不对称、贴壁气流冲刷水冷壁以及着火距离过长等问题。分析其原因为:MBEL技术的W型火焰锅炉具有下炉膛大、上炉膛小的特点,不能忽略折烟角对炉内流场的影响。通过在三次风喷口处加装导流板和改变三次风量及下倾角度可以解决原有工况存在的问题。加装导流板后随着三次风量的增加,炉内流场对称性变好,炉内结渣情况也得到好转,一二次风混合距离变短。但当三次风风量过大时,由于拱部气流量太小,射流刚性减弱,流场偏斜效果加剧。同时三次风风量过大容易引起冲刷冷灰斗等问题。
在研究三次风角度变化对炉内流场的影响时发现,随着三次风入射角度的减小,三次风对一二次风的向下引流作用变小,对炉内流场偏斜趋势的改善作用变小,同时,在炉内流场偏斜效果加剧时所能达到的最大三次风风量减小。
W-shaped flame boiler, with its own high-temperature and long-flame characteristics, is suitable for burning low volatile anthracite fuel. At present, there are more than 60 utility W-shaped flame boilers, and some of these of the MBEL company need to be resolved, but current research in this area rarely.
In this thesis, the aerodynamic fields in a 300MW W-shaped flame boiler`s furnace , which is designed by MBEL company, were studied on the single-phase cold model, which is built on the Similarity Theory in accordance with the ratio of 1:15 and an IFA300 constant-temperature anemometer system was used to measure the air velocity in the model. The experimental results reveals that there is a W-shaped flame in the furnace under the present work condition, but the W-shaped flame is asymmetric. This condition is improvement after the Air deflector is fixed. With the tertiary air increasing, the W-shaped flame Has become asymmetric and clinkering rate is diminution. but as the momentum of the tertiary air is decreased, the asymmetric W-shaped flame Become serious.
In the study of dip angle of the tertiary air we found that with the tertiary air reduced, its betterment of the asymmetric W-shaped flame is weaken and the flow field become asymmetric serious with a slight increase of the tertiary air.
引文
1戴和武,李瑞,李连仲,等.我国动力煤利用的若干问题.中国煤炭. 1997, 23(9): 12~15
2王妍,李京文.我国煤炭消费现状与未来煤炭需求预测.中国人口·资源与环境. 2008
3许传凯,袁颖大型燃煤电厂锅炉运行现状分析〔J〕.中国电力,2(X)3,36(1):1~5.
4许传凯,许云松.我国低挥发分煤燃烧技术的发展.技术经济综述.2001
5车刚,苗长信,郭玉泉.W型火焰锅炉的燃烧机理及应用介绍[J].山东电力技术. 2002, (4): 39-41.
6张文宏.W型火焰锅炉炉内空气动力场的试验研究[J].动力工程. 1992, 12(4): 14-23.
7魏小林,徐通模,惠世恩.W型火焰锅炉冷态模型试验及数值计算[J].动力工程,1994,14(1):27-32
8王笃奎,曾汉才.W型火焰锅炉冷态试验及最佳配风方式的研究[J].华中电力,2001,14(3):18-21.
9孙保民,徐旭常.W型火焰煤粉锅炉炉内过程的综合数值模拟及流场的实验研究[J].燃烧科学与技术,1995,16(4):230-235.
10许卫疆,闫晓,孙新国,惠世恩,徐通模.三次风对W型火焰锅炉空气动力场的影响[J].西安交通大学学报,2001,35(1):108-110.
11袁颖,相大光.我国W火焰双拱锅炉燃烧性能调查研究.中国电力,1996,32(11):1~6
12 S. C. Stultz, J. B. Kitto. Steam/Its Generation and Use. 40th edition B&W Barberton, Ohil, U.S.A, 1992
13 John Reason. How Fuel Volatility Impacts Boiler Design and Operation. Power. 1983,(12):145~148
14 Mccormick N J. Inverse radiative transfer problems: areview [J].Nuclear Science and Engineering, 1992(112): 185~198.
15 W. M. Robsenowetal. Handbook of Heat Trailsfef. Mc Graw Hill, 2001
16 J. C. Bokar. The estimation of spatially varying albedo and optical thickness in a radiating slab using artifical neuralnetworks [J].International Comm.HeatTransfer,1999, 26(3): 359~363.
17李之光.相似与模化.国防工业出版社, 1982
18黄伟,李文军. W型火焰锅炉燃用低挥发份无烟煤的试验研究.动力工程. 2005, 25(6): 813~819
19郭晓宁. W型火焰锅炉对低挥发份煤的适应性及其燃烧系统设计分析.热能动力工程. 1996, 11(3): 165~170
20余战英,谭厚章,徐通模,惠世恩. W型火焰燃烧的实验研究.工程热物理学报. 2004, 25: 233~236
21王龙发.适应多煤种负荷调节的W型燃烧方式.华东电力. 1984, (10): 83~86
22车刚,何立明,惠世恩,徐通模.改造W型火焰锅炉结构的实验研究.锅炉技术. 2000, 31(5): 6~17
23何立明,车刚,徐通模,等.炉膛喉口面积对W型火焰锅炉炉内空气动力场的影响.西安交通大学学报. 2000, 34(7): 12~15
24何佩敖.无烟煤的U型、W型火焰燃烧技术.电站系统工程. 1989, (2): 44~60
25毕玉森,陈国辉.低挥发分煤种与W型火焰锅炉.热力发电. 2005, (7): 7~10
26朱炳煌.大型锅炉低反应能力煤的燃烧.东方锅炉. 1988, (2): 23~29
27张玉斌.不同二次风分配对W型火焰炉炉内流动特性的影响.哈尔滨工业大学硕士学位论文. 2007
28许传凯.低挥发份煤的燃烧与“W”型火焰锅炉若干问题研究.中国电力. 2004, 37(7): 37~40
29郭玉泉. W火焰锅炉燃烧及运行特性试验研究.山东大学硕士学位论文. 2006
30高春文. W型火焰锅炉的运行分析[J].山西电力,2002(3): 12~14.
31阎维平,高正阳,姜平. 300MW机组W型火焰锅炉燃烧调整试验研究[J].动力工程, 1999, 19(1): 23~26.
32张文元,刘春明,赵运亮,等.中储式热风送粉W型火焰锅炉燃烧调整分析[J].电力学报, 2002, 17(2):112~114.
33田新荆,万中平,林协丰.W型火焰锅炉冷态流场的研究.湖北电力, 2002, 26 (1):20~23
34段秋刚,邓丽萍,杨文杰.阳泉二电厂300MW机组燃烧控制系统特点及应用.山西电力技术. 1999, (1):118~122
35汪健生,郑杰,舒玮.热线风速仪同时测量流场速度与温度.实验力学.1998,13(3):393~398
36张万路.热线风速仪在线测量的修正模型.北京100013:中国计量科学研究院. 2000, 24(4):46~49
37熊蔚立,龚柏云.W型火焰下喷燃烧锅炉技术特点及选型参考.湖南电力. 1999, 6
38余岳溪,李乃钊,罗萌,徐齐胜,宋景慧,温智勇.W形火焰锅炉的风量和煤粉均匀特性对燃烧的影响.广东电力,2002,15(3):16~18
39高原. 1025t/h W型火焰锅炉气固流动特性的数值模拟研究.哈尔滨工业大学硕士毕业论文. 2005
40张海,吕俊复等. W型火焰锅炉燃烧问题的分析和解决方法.动力工程. 2007, (3):1~9
41 P. Moin. Progress in large eddy simulation of turbulence flows. AIAA paper, 97-15761, 1997
42 S. Jakirlic, J. Volkert, H. Pascal, et al.DNS, Experimental and Modelling Study of Axially Compressed In-cylinder Swirling Flow.Int. J. Heat and Fluid Flow. 2000, 21: 627-639
43 David Tillman, Dao Duong. Managing Slagging at Monroe Power Plant Using On-line Coal Analysis and Fuel Blending. Fuel Processing Technology. 2007, 5: 1~5
44 Marion Gross, Michel Soulard, Philippe Caullet, etc. Synthesis of Faujasite From Coal Fly Ashes Under Smooth Temperature and Pressure Conditions. Microporous and Mesoporous Materials. 2007, 6(1): 67~76
45 Antonio Copado, Francisco Rodríguez. CESAR–SIRE: Advanced Software for Boiler Efficiency and NOx Optimization. Feul. 2002, 81(5): 619~626
46 J. R. Fan, X. H. Liang, L. H. Chen and K. F. Cen. Modeling of NOx Emissions From a W-shaped Boiler Furnace Under Diffent Operating Conditions. Energy. 1998, 23(12):1051~1055
47 S.P. Khare, T.F. Wall, A.Z. Farida, etc. Factors Influencing the Ignition of Flames From Air-fired Swirl pf Burners Retrofitted to Oxy-fuel. Fuel. 2008, 87(7): 1042~1049
48 D. B. Spalding. Mathematical Modles of Continuous Combustion, Emissions From Cotinuous Combustion System. Plenum Press, 1972
49 N.H. Qamar, G.J. Nathan, etc. The Effect of Global Mixing on Soot Volume Fraction: Measurements in Simple Jet, Precessing Jet, and Bluff Body Flames. Proceedings of the Combustion Institute. 2005, 30(1): 1493-1500
50 P. Kumar, D.P. Mishra. Effects of Bluff-body Shape on LPG–H2 Jet Diffusion Flame. International Journal of Hydrogen Energy. 2008, 33(10): 2578-2585
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54 Pope S. B. Turbulent Flow. New York : Cambridge University Press, 2000
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56 S. Benyahia, H. Arastoopour. Simulation of Particles and Gas Flow Behavior in The Riser Section of a Circulating Fluidized Bed Using the Kinetic Theory Approach for the Particulate Phase. Powder Technology. 2000, 112:24~33
2王妍,李京文.我国煤炭消费现状与未来煤炭需求预测.中国人口·资源与环境. 2008
3许传凯,袁颖大型燃煤电厂锅炉运行现状分析〔J〕.中国电力,2(X)3,36(1):1~5.
4许传凯,许云松.我国低挥发分煤燃烧技术的发展.技术经济综述.2001
5车刚,苗长信,郭玉泉.W型火焰锅炉的燃烧机理及应用介绍[J].山东电力技术. 2002, (4): 39-41.
6张文宏.W型火焰锅炉炉内空气动力场的试验研究[J].动力工程. 1992, 12(4): 14-23.
7魏小林,徐通模,惠世恩.W型火焰锅炉冷态模型试验及数值计算[J].动力工程,1994,14(1):27-32
8王笃奎,曾汉才.W型火焰锅炉冷态试验及最佳配风方式的研究[J].华中电力,2001,14(3):18-21.
9孙保民,徐旭常.W型火焰煤粉锅炉炉内过程的综合数值模拟及流场的实验研究[J].燃烧科学与技术,1995,16(4):230-235.
10许卫疆,闫晓,孙新国,惠世恩,徐通模.三次风对W型火焰锅炉空气动力场的影响[J].西安交通大学学报,2001,35(1):108-110.
11袁颖,相大光.我国W火焰双拱锅炉燃烧性能调查研究.中国电力,1996,32(11):1~6
12 S. C. Stultz, J. B. Kitto. Steam/Its Generation and Use. 40th edition B&W Barberton, Ohil, U.S.A, 1992
13 John Reason. How Fuel Volatility Impacts Boiler Design and Operation. Power. 1983,(12):145~148
14 Mccormick N J. Inverse radiative transfer problems: areview [J].Nuclear Science and Engineering, 1992(112): 185~198.
15 W. M. Robsenowetal. Handbook of Heat Trailsfef. Mc Graw Hill, 2001
16 J. C. Bokar. The estimation of spatially varying albedo and optical thickness in a radiating slab using artifical neuralnetworks [J].International Comm.HeatTransfer,1999, 26(3): 359~363.
17李之光.相似与模化.国防工业出版社, 1982
18黄伟,李文军. W型火焰锅炉燃用低挥发份无烟煤的试验研究.动力工程. 2005, 25(6): 813~819
19郭晓宁. W型火焰锅炉对低挥发份煤的适应性及其燃烧系统设计分析.热能动力工程. 1996, 11(3): 165~170
20余战英,谭厚章,徐通模,惠世恩. W型火焰燃烧的实验研究.工程热物理学报. 2004, 25: 233~236
21王龙发.适应多煤种负荷调节的W型燃烧方式.华东电力. 1984, (10): 83~86
22车刚,何立明,惠世恩,徐通模.改造W型火焰锅炉结构的实验研究.锅炉技术. 2000, 31(5): 6~17
23何立明,车刚,徐通模,等.炉膛喉口面积对W型火焰锅炉炉内空气动力场的影响.西安交通大学学报. 2000, 34(7): 12~15
24何佩敖.无烟煤的U型、W型火焰燃烧技术.电站系统工程. 1989, (2): 44~60
25毕玉森,陈国辉.低挥发分煤种与W型火焰锅炉.热力发电. 2005, (7): 7~10
26朱炳煌.大型锅炉低反应能力煤的燃烧.东方锅炉. 1988, (2): 23~29
27张玉斌.不同二次风分配对W型火焰炉炉内流动特性的影响.哈尔滨工业大学硕士学位论文. 2007
28许传凯.低挥发份煤的燃烧与“W”型火焰锅炉若干问题研究.中国电力. 2004, 37(7): 37~40
29郭玉泉. W火焰锅炉燃烧及运行特性试验研究.山东大学硕士学位论文. 2006
30高春文. W型火焰锅炉的运行分析[J].山西电力,2002(3): 12~14.
31阎维平,高正阳,姜平. 300MW机组W型火焰锅炉燃烧调整试验研究[J].动力工程, 1999, 19(1): 23~26.
32张文元,刘春明,赵运亮,等.中储式热风送粉W型火焰锅炉燃烧调整分析[J].电力学报, 2002, 17(2):112~114.
33田新荆,万中平,林协丰.W型火焰锅炉冷态流场的研究.湖北电力, 2002, 26 (1):20~23
34段秋刚,邓丽萍,杨文杰.阳泉二电厂300MW机组燃烧控制系统特点及应用.山西电力技术. 1999, (1):118~122
35汪健生,郑杰,舒玮.热线风速仪同时测量流场速度与温度.实验力学.1998,13(3):393~398
36张万路.热线风速仪在线测量的修正模型.北京100013:中国计量科学研究院. 2000, 24(4):46~49
37熊蔚立,龚柏云.W型火焰下喷燃烧锅炉技术特点及选型参考.湖南电力. 1999, 6
38余岳溪,李乃钊,罗萌,徐齐胜,宋景慧,温智勇.W形火焰锅炉的风量和煤粉均匀特性对燃烧的影响.广东电力,2002,15(3):16~18
39高原. 1025t/h W型火焰锅炉气固流动特性的数值模拟研究.哈尔滨工业大学硕士毕业论文. 2005
40张海,吕俊复等. W型火焰锅炉燃烧问题的分析和解决方法.动力工程. 2007, (3):1~9
41 P. Moin. Progress in large eddy simulation of turbulence flows. AIAA paper, 97-15761, 1997
42 S. Jakirlic, J. Volkert, H. Pascal, et al.DNS, Experimental and Modelling Study of Axially Compressed In-cylinder Swirling Flow.Int. J. Heat and Fluid Flow. 2000, 21: 627-639
43 David Tillman, Dao Duong. Managing Slagging at Monroe Power Plant Using On-line Coal Analysis and Fuel Blending. Fuel Processing Technology. 2007, 5: 1~5
44 Marion Gross, Michel Soulard, Philippe Caullet, etc. Synthesis of Faujasite From Coal Fly Ashes Under Smooth Temperature and Pressure Conditions. Microporous and Mesoporous Materials. 2007, 6(1): 67~76
45 Antonio Copado, Francisco Rodríguez. CESAR–SIRE: Advanced Software for Boiler Efficiency and NOx Optimization. Feul. 2002, 81(5): 619~626
46 J. R. Fan, X. H. Liang, L. H. Chen and K. F. Cen. Modeling of NOx Emissions From a W-shaped Boiler Furnace Under Diffent Operating Conditions. Energy. 1998, 23(12):1051~1055
47 S.P. Khare, T.F. Wall, A.Z. Farida, etc. Factors Influencing the Ignition of Flames From Air-fired Swirl pf Burners Retrofitted to Oxy-fuel. Fuel. 2008, 87(7): 1042~1049
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