300MW锅炉启动过程汽包应力分析与疲劳计算
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摘要
高参数、大容量参与调峰的机组启停和变负荷过程中,较快的升压和降压以及蒸汽温度变化均会使锅炉汽包材料所承受较大的机械应力和热应力化,而频繁交变的机械应力和热应力将使金属材料产生的疲劳损伤增大,缩短锅炉汽包的使用寿命。因此开展对锅炉汽包的相关研究工作,包括锅炉汽包的瞬态温度场和瞬态应力场分布,以及在此基础上进行汽包的低周疲劳寿命计算等,对提高机组运行的安全性和可靠性具有重要的指导意义。
本课题以某发电厂300MW单元机组的HG1025/18.2/540/540-PM2型亚临界自然循环锅炉的汽包为仿真研究对象,在获得试验数据的基础上,对该汽包的瞬态温度场、瞬态应力场、强度计算和低周疲劳寿命等方面开展了多学科的交叉研究。文章主要从以下几个方面进行了探讨。
首先,本文建立了该汽包结构不连续区域的有限元模型,然后利用采集的数据作为计算的边界条件,采用三维有限元理论,运用国际通用大型有限元分析软件ANSYS,对机组汽包的瞬态温度场、热应力、机械应力和总应力(热和机械的耦合应力)进行了详细的计算。
其次,通过对计算结果的分析,找出了汽包应力最大值的位置,并求出了危险点机械应力和总应力与蒸汽压力的比例关系。应用ANSYS程序提供的优化设计方法对汽包的局部结构进行了优化设计。作为对前面工作的总结,根据ANSYS程序的二次开发功能介绍了汽包瞬态应力分析专用程序的开发过程。
论文最后引用ANSYS三维有限元瞬态分析的结果进行了锅炉汽包低周疲劳寿命计算,并与传统算法的计算结果进行了比较分析。
Recent years, along with the growth of national economy, the peak-valley difference of electrical network increases day by day, a lot of thermoelectricity generator units with high running parameters and large capacity have to take part in changing the loads and even to startup-halt for adjusting the peak output. The diameter and wall thickness of the boiler drum is relative big. During the process of starting or stopping and altering loads, the pressure rising or dropping and temperature varying will make mechanical and thermal stress of the drum greatly change. The varying of the stress will result in fatigue damage to drum material and shorten the service life of the drum.
For this reason, people had paid great attention to this and a lot of research work about drum was carried out. Among these work, the distribution of transient temperature field and stress field, the calculation of low-cycle fatigue life are significant to ensure boiler in good condition and safety running.
The thesis takes 300MW sub-critical natural circulation boiler HG1025/ 18.2/540/540-PM2 drum of a Power Plant as object. Based on test data, the multi-disciplinary research across transient temperature field, transient stress field, Low-cycle fatigue life etc was carried out. The thesis mainly carried on the discussion in the followed respects.
Firstly, author built a calculating model of the discontinuous area.Then utilized the test data as border condition of the model. The three-dimensional finite element unit was adopted; ANSYS software were used and the transient temperature field, thermal stress, mechanical stress, total stress of the drum were calculated to the model.
Secondly, the position of maximum stress of the drum was found out through the analysis of calculating result, some proportionate regulation between mechanical stresses or total stresses and steam pressure also found out. Then used the optimum function of ANSYS applied to the optimization design of part structure. Finally, processed calculation of the Low-cycle fatigue life.
本课题以某发电厂300MW单元机组的HG1025/18.2/540/540-PM2型亚临界自然循环锅炉的汽包为仿真研究对象,在获得试验数据的基础上,对该汽包的瞬态温度场、瞬态应力场、强度计算和低周疲劳寿命等方面开展了多学科的交叉研究。文章主要从以下几个方面进行了探讨。
首先,本文建立了该汽包结构不连续区域的有限元模型,然后利用采集的数据作为计算的边界条件,采用三维有限元理论,运用国际通用大型有限元分析软件ANSYS,对机组汽包的瞬态温度场、热应力、机械应力和总应力(热和机械的耦合应力)进行了详细的计算。
其次,通过对计算结果的分析,找出了汽包应力最大值的位置,并求出了危险点机械应力和总应力与蒸汽压力的比例关系。应用ANSYS程序提供的优化设计方法对汽包的局部结构进行了优化设计。作为对前面工作的总结,根据ANSYS程序的二次开发功能介绍了汽包瞬态应力分析专用程序的开发过程。
论文最后引用ANSYS三维有限元瞬态分析的结果进行了锅炉汽包低周疲劳寿命计算,并与传统算法的计算结果进行了比较分析。
Recent years, along with the growth of national economy, the peak-valley difference of electrical network increases day by day, a lot of thermoelectricity generator units with high running parameters and large capacity have to take part in changing the loads and even to startup-halt for adjusting the peak output. The diameter and wall thickness of the boiler drum is relative big. During the process of starting or stopping and altering loads, the pressure rising or dropping and temperature varying will make mechanical and thermal stress of the drum greatly change. The varying of the stress will result in fatigue damage to drum material and shorten the service life of the drum.
For this reason, people had paid great attention to this and a lot of research work about drum was carried out. Among these work, the distribution of transient temperature field and stress field, the calculation of low-cycle fatigue life are significant to ensure boiler in good condition and safety running.
The thesis takes 300MW sub-critical natural circulation boiler HG1025/ 18.2/540/540-PM2 drum of a Power Plant as object. Based on test data, the multi-disciplinary research across transient temperature field, transient stress field, Low-cycle fatigue life etc was carried out. The thesis mainly carried on the discussion in the followed respects.
Firstly, author built a calculating model of the discontinuous area.Then utilized the test data as border condition of the model. The three-dimensional finite element unit was adopted; ANSYS software were used and the transient temperature field, thermal stress, mechanical stress, total stress of the drum were calculated to the model.
Secondly, the position of maximum stress of the drum was found out through the analysis of calculating result, some proportionate regulation between mechanical stresses or total stresses and steam pressure also found out. Then used the optimum function of ANSYS applied to the optimization design of part structure. Finally, processed calculation of the Low-cycle fatigue life.
引文
1.王勇.电厂锅炉汽包低周疲劳寿命评价技术及压力管道结构分析研究: [博士学位论文].浙江:浙江大学材料化工学院, 2002: 1~3
2.周昊,池作和,蒋啸,岑可法.大容量直流锅炉启动过程优化.电站系统工程,1995,11 (4): 33~36
3.雷定威.锅炉汽包裂纹处理方法研究.湖南电力,1997. (2): 1~6
4.黄飞,陶进庆.锅炉启停过程中汽包壁环向温度场的数值计算.江苏锅炉, 2000. (7): 14~16
5.沈月芬,贾鸿祥.国产125MW锅炉汽包疲劳寿命计算.锅炉技术,1985. (8): 1~12
6.程丰渊,梁剑平.调峰机组锅炉汽包的强度计算.锅炉制造,1982. (56): 26~30
7.郑思定,盛建国.调峰机组锅炉汽包壁温度场和热应力分析和低周疲劳设计.动力工程,1988. 8(6): 18~25
8.邓文俭, 1025t/h自然循环锅炉汽包的温度场和疲劳寿命损耗.华北电力技术,1994. (9): 13~16
9.沈月芬,曹子栋,李斌等.锅炉汽包管接头组合结构的温度分布二维有限元分析.西安交通大学学报,1995 (05): 100 ~105
10. Zhao Tiecheng, Shen Yuefen, Zhu Guozhen. Temperature field calculation of boiler drum-finite element analysis of 3-D unsteady variable character uneven material heat conduction problem. Proceedings of the Chinese Society of Electrical Engineering v 17 n 4 July 1997: 217~220
11.商福民,吕邦泰,庞止平.锅炉汽包壁上下温差热应力有限元分析.华北电力大学学报,1999.26 (01): 52~56
12.联邦德国标准Technical Rules for Steam Boilers(TRD301),Edition April 1975.
13. BS5500-91,Specification for Unfire Fusion Welded Pressure Vessel.1976
14. Taler J, Weglowski B, Zima W, etal. Analysis of thermal stresses in a boiler drum during start-up. Journal of Pressure Vessel Technology. Transactions of the ASME, 1999.121(1): 84~93
15. Isreb M. Superheater minimum stress unit start-up option of coal-fired powerplants Computers and Structures,1997.62(5): 865~875
16. Kim T. S.,Lee, D. K.;Ro, S. T. Analysis of thermal stress evolution in the steam drum during start-up of a heat recovery steam generator. Applied Thermal Engineering, 2000.20 (11): 977~992
17.师俊平,李蹊,刘协会.汽包在复杂载荷作用下的应力分析.机械科学与技术,1997.16(2): 240~244
18.赵铁成,沈月芬,梁艳明等.电站锅炉锅筒内压应力三维有限元分析.中国电机工程学报,1999.19 (01): 31~33
19.邓文俭,李林. 300MW仿真机组锅炉汽包温度场及疲劳寿命损耗的数学模型.山东电力技术,1995.1: 73~79
20.阎顺林,吕邦泰,李永华.锅炉汽包封头的不稳定温度场及应力场的有限元分析.华北电力大学学报(自然科学版),1994.(01): 62~67
21. Lorenzo,C. F . and Merrill , W. C ,“Life Extending Control,”(In) Proceedings of the 1991 American Automatic Control Conference, Publicated by American Automatic Control Council, Green Valley, AZ ,USA. 1991,Vo l.2,pp 1081~1095
22.裴玉刚,沈月芬,杨天亮,曹子栋,吴静.锅炉汽包疲劳寿命管理系统的研究,西安交通大学学报, 1999,33(5): 63~65
23. Deutscher Dampfkessel-Ausschu(DDA).Technical Rules for Steam Boilers(TRD)301 Annex 1,Calculation for cyclic loading due to pulsating internal pressure or combined changes of internal pressure and temperature , Essen: Vereinigung der Technischen uberwachungs-Vereine e.V.,1975: 150
24.吕邦泰,沈月芬.锅炉承压部件强度及寿命.北京:水利电力出版社,1992
25. ASME Boiler and Pressure Vessel Committee. Rules for construction of pressure vessels.New York: ASME United Engineering Center,1974: 318
26.徐礼华.汽包上下壁温差对锅炉运行安全性影响的研究.电力技术,1992,(1): 2~7.
27.гост25859.钢制容器及设备低周载荷下强度计算方法及规定(前苏联).
28.王金瑞,李益民等.电站高压锅炉汽包钢的疲劳性能及疲劳分析曲线.全国第四届电站构件失效分析与寿命管理学术会议,承德,1994.
29.余伟炜,高炳军.ANSYS在机械与化工装备中的应用.北京:中国水利水电出版社,2005: 35~38
30.徐灏.疲劳强度.北京:高等教育出版社,1988: 125~130
31. Smith F W. The surface Crack: Physical Problems and Computational Solution. ASME, 1972: 42~45
32. R P . Reway and N F. Rieger.Survey of Steam Turbine Blade Failure, EPRI, CS3891, 1985: 235~253
33.徐秉业,刘信声.应用弹塑性力学.北京:清华大学出版社,2003:180~191
34. Saeed Moaveni著.欧阳宇等译.有限元分析——ANSYS理论与应用.北京:电子工业出版社,2003: 50~53
35. Isreb M. Superheater minimum stress unit start-up option of coal-fired power plants Computers and Structures, 1997.62 (5): 865~875.
36.江爱林. 300MW锅炉汽包应力分析与裂纹计算:[硕士学位论文].武汉理工大学能源与动力工程学院, 2005: 26~31
37.西安交通大学.火力发电厂传热原理与实践,1977: 105~107
38.王永芳.电厂关键设备寿命在线监测系统研究: [硕士学位论文].华北电力大学机械设计及理论专业,2004: 11~15
39.唐兴伦,范群波,张朝晖等. ANSYS工程应用教程(热与电磁学篇).北京:中国铁道出版社,2003: 79~80
40.梁艳明,沈月芬.锅炉锅筒在实测边界条件下的应力场三维有限元分析.西安交通大学学报,1999,33(1): 74~76
41. ANSYS,Inc. Release 10.0 Documentation for ANSYS, ANSYS HELP.
42.李之光,王铣庆.锅炉受压元件的强度分析与设计.北京:机械工业出版社, 1986: 15~18
43.吴富民.结构疲劳强度,西安:西北工业大学出版社,1985: 60~62
44. Langer B F.Design of pressure vessels for Low cycle fatigue.Journal of Basic Engineering ASME,1962,84: 389~402
45. Holman,jack philo.Heat transfer.Fifths.Ed.Auckland,McGraw-Hill,1981
46. Nichole R W.Pressure vessel engineering England.1971: 59~100
47.郑克,刘志刚.辛店电厂DG670/140-2型锅炉汽包低周疲劳寿命研究.热力发电,2000(3) : 50~54
48.李丽萍,庞凯迈.炉汽包疲劳寿命的估算.华北水利水电学院学报,1999,20(2): 63~65
49. ASME Boiler and Pressel Code. Section VII, Divi-sion, 1980,2: 1~78
2.周昊,池作和,蒋啸,岑可法.大容量直流锅炉启动过程优化.电站系统工程,1995,11 (4): 33~36
3.雷定威.锅炉汽包裂纹处理方法研究.湖南电力,1997. (2): 1~6
4.黄飞,陶进庆.锅炉启停过程中汽包壁环向温度场的数值计算.江苏锅炉, 2000. (7): 14~16
5.沈月芬,贾鸿祥.国产125MW锅炉汽包疲劳寿命计算.锅炉技术,1985. (8): 1~12
6.程丰渊,梁剑平.调峰机组锅炉汽包的强度计算.锅炉制造,1982. (56): 26~30
7.郑思定,盛建国.调峰机组锅炉汽包壁温度场和热应力分析和低周疲劳设计.动力工程,1988. 8(6): 18~25
8.邓文俭, 1025t/h自然循环锅炉汽包的温度场和疲劳寿命损耗.华北电力技术,1994. (9): 13~16
9.沈月芬,曹子栋,李斌等.锅炉汽包管接头组合结构的温度分布二维有限元分析.西安交通大学学报,1995 (05): 100 ~105
10. Zhao Tiecheng, Shen Yuefen, Zhu Guozhen. Temperature field calculation of boiler drum-finite element analysis of 3-D unsteady variable character uneven material heat conduction problem. Proceedings of the Chinese Society of Electrical Engineering v 17 n 4 July 1997: 217~220
11.商福民,吕邦泰,庞止平.锅炉汽包壁上下温差热应力有限元分析.华北电力大学学报,1999.26 (01): 52~56
12.联邦德国标准Technical Rules for Steam Boilers(TRD301),Edition April 1975.
13. BS5500-91,Specification for Unfire Fusion Welded Pressure Vessel.1976
14. Taler J, Weglowski B, Zima W, etal. Analysis of thermal stresses in a boiler drum during start-up. Journal of Pressure Vessel Technology. Transactions of the ASME, 1999.121(1): 84~93
15. Isreb M. Superheater minimum stress unit start-up option of coal-fired powerplants Computers and Structures,1997.62(5): 865~875
16. Kim T. S.,Lee, D. K.;Ro, S. T. Analysis of thermal stress evolution in the steam drum during start-up of a heat recovery steam generator. Applied Thermal Engineering, 2000.20 (11): 977~992
17.师俊平,李蹊,刘协会.汽包在复杂载荷作用下的应力分析.机械科学与技术,1997.16(2): 240~244
18.赵铁成,沈月芬,梁艳明等.电站锅炉锅筒内压应力三维有限元分析.中国电机工程学报,1999.19 (01): 31~33
19.邓文俭,李林. 300MW仿真机组锅炉汽包温度场及疲劳寿命损耗的数学模型.山东电力技术,1995.1: 73~79
20.阎顺林,吕邦泰,李永华.锅炉汽包封头的不稳定温度场及应力场的有限元分析.华北电力大学学报(自然科学版),1994.(01): 62~67
21. Lorenzo,C. F . and Merrill , W. C ,“Life Extending Control,”(In) Proceedings of the 1991 American Automatic Control Conference, Publicated by American Automatic Control Council, Green Valley, AZ ,USA. 1991,Vo l.2,pp 1081~1095
22.裴玉刚,沈月芬,杨天亮,曹子栋,吴静.锅炉汽包疲劳寿命管理系统的研究,西安交通大学学报, 1999,33(5): 63~65
23. Deutscher Dampfkessel-Ausschu(DDA).Technical Rules for Steam Boilers(TRD)301 Annex 1,Calculation for cyclic loading due to pulsating internal pressure or combined changes of internal pressure and temperature , Essen: Vereinigung der Technischen uberwachungs-Vereine e.V.,1975: 150
24.吕邦泰,沈月芬.锅炉承压部件强度及寿命.北京:水利电力出版社,1992
25. ASME Boiler and Pressure Vessel Committee. Rules for construction of pressure vessels.New York: ASME United Engineering Center,1974: 318
26.徐礼华.汽包上下壁温差对锅炉运行安全性影响的研究.电力技术,1992,(1): 2~7.
27.гост25859.钢制容器及设备低周载荷下强度计算方法及规定(前苏联).
28.王金瑞,李益民等.电站高压锅炉汽包钢的疲劳性能及疲劳分析曲线.全国第四届电站构件失效分析与寿命管理学术会议,承德,1994.
29.余伟炜,高炳军.ANSYS在机械与化工装备中的应用.北京:中国水利水电出版社,2005: 35~38
30.徐灏.疲劳强度.北京:高等教育出版社,1988: 125~130
31. Smith F W. The surface Crack: Physical Problems and Computational Solution. ASME, 1972: 42~45
32. R P . Reway and N F. Rieger.Survey of Steam Turbine Blade Failure, EPRI, CS3891, 1985: 235~253
33.徐秉业,刘信声.应用弹塑性力学.北京:清华大学出版社,2003:180~191
34. Saeed Moaveni著.欧阳宇等译.有限元分析——ANSYS理论与应用.北京:电子工业出版社,2003: 50~53
35. Isreb M. Superheater minimum stress unit start-up option of coal-fired power plants Computers and Structures, 1997.62 (5): 865~875.
36.江爱林. 300MW锅炉汽包应力分析与裂纹计算:[硕士学位论文].武汉理工大学能源与动力工程学院, 2005: 26~31
37.西安交通大学.火力发电厂传热原理与实践,1977: 105~107
38.王永芳.电厂关键设备寿命在线监测系统研究: [硕士学位论文].华北电力大学机械设计及理论专业,2004: 11~15
39.唐兴伦,范群波,张朝晖等. ANSYS工程应用教程(热与电磁学篇).北京:中国铁道出版社,2003: 79~80
40.梁艳明,沈月芬.锅炉锅筒在实测边界条件下的应力场三维有限元分析.西安交通大学学报,1999,33(1): 74~76
41. ANSYS,Inc. Release 10.0 Documentation for ANSYS, ANSYS HELP.
42.李之光,王铣庆.锅炉受压元件的强度分析与设计.北京:机械工业出版社, 1986: 15~18
43.吴富民.结构疲劳强度,西安:西北工业大学出版社,1985: 60~62
44. Langer B F.Design of pressure vessels for Low cycle fatigue.Journal of Basic Engineering ASME,1962,84: 389~402
45. Holman,jack philo.Heat transfer.Fifths.Ed.Auckland,McGraw-Hill,1981
46. Nichole R W.Pressure vessel engineering England.1971: 59~100
47.郑克,刘志刚.辛店电厂DG670/140-2型锅炉汽包低周疲劳寿命研究.热力发电,2000(3) : 50~54
48.李丽萍,庞凯迈.炉汽包疲劳寿命的估算.华北水利水电学院学报,1999,20(2): 63~65
49. ASME Boiler and Pressel Code. Section VII, Divi-sion, 1980,2: 1~78