百万等级给水泵汽轮机高速转子特性分析
摘要
转子是汽轮机设备中最为关键的部件之一。其优劣往往决定了整个机组的安全可靠性。在发电用汽轮机转子的研发中,转子轴向推力与转子动态特性一直是设计者的关注重点,而在给水泵汽轮机领域,给水泵需要变转速运行的特点,更是为给水泵汽轮机转子的研发带来挑战。
随着具有明显高效、节能和环保优势的超超临界1000MW汽轮发电机组在我国的迅猛发展,配套的22.5MW驱动锅炉给水泵汽轮机的市场需求也越来越大、竞争越来越激烈。如何设计出安全可靠又经济高效的22.5MW给水泵汽轮机,成为在该市场立足的关键。
然而,在对22.5MW等级给水泵汽轮机的研发中,存在着前所未有的挑战。由于机组功率较大,巨大的轴向推力在单流结构中很难得到平衡,若采用双流设计,又会大大增加机组的制造成本与电厂的建设成本,使产品不具竞争力;此外,高速转子变速范围广,其临界转速避开工作转速的难度大,对其进行设计调整又会牵涉到轴向推力的改变,如此“牵一发而动全身”的局面使得22.5MW给水泵汽轮机转子的研发形式扑朔迷离。
论文以配套1000MW等级超超临界汽轮发电机组的22.5MW驱动锅炉给水泵汽轮机为研究对象;针对机组“功率高、推力大、转速范围广”的特性及开发难点,对其高速转子轴向推力和动态特性进行了计算和研究分析;缓解了转子轴向推力、临界转速方面互相影响、互相制约的矛盾;证明了单流式设计仍然适用于22.5MW给水泵汽轮机,保证其安全、稳定、高效地运行。
The rotor is one of the most important part of steam turbine. The reliability of unit mostly depend on it. In the design of general rotor of steam turbine, the axial thrust force and other dynamic character are usually within designer’s concern. While designing BFPT, the changing speed brings great challenges.
With the rapidly development of 1000MW extra supercritical pressure units in China, which have obvious advantages of high-efficiency, saving-energy and low-pollution, the demand of matched 22.5MW BFPT is becoming bigger and bigger. It is important to prepare a reliable and efficient 22.5MW BFPT for the market.
However, due to the great output of the 22.5MW BFPT, huge axial thrust force of rotor can hardly be balanced. If the double-flow design is taken, the costs of turbine manufacture and plant construction will highly rise with no advantages in marketing competition. On the other hand, due to the large scale of rotor rated speed, it is difficult to make the critical speed far away from rated speed. The measure to adjust critical speed will change the axial thrust force of rotor at the same time. A delicate circumstance has to be faced while designing the rotor of 22.5MW BFPT.
This research is made for 22.5MW BFPT for 1000MW extra supercritical pressure power plant. Considering the great output, huge axial thrust force and large scale of speed of the rotor, calculations and analysis are made to investigate the axial thrust force and the dynamic character of the high speed rotor. The conflict between the axial thrust force and the critical speed is well solved. It is proved that the design of single casing and single flow is still suitable to 22.5MW BFPT. The security, stability and high efficiency of this BFPT can be guaranteed.
随着具有明显高效、节能和环保优势的超超临界1000MW汽轮发电机组在我国的迅猛发展,配套的22.5MW驱动锅炉给水泵汽轮机的市场需求也越来越大、竞争越来越激烈。如何设计出安全可靠又经济高效的22.5MW给水泵汽轮机,成为在该市场立足的关键。
然而,在对22.5MW等级给水泵汽轮机的研发中,存在着前所未有的挑战。由于机组功率较大,巨大的轴向推力在单流结构中很难得到平衡,若采用双流设计,又会大大增加机组的制造成本与电厂的建设成本,使产品不具竞争力;此外,高速转子变速范围广,其临界转速避开工作转速的难度大,对其进行设计调整又会牵涉到轴向推力的改变,如此“牵一发而动全身”的局面使得22.5MW给水泵汽轮机转子的研发形式扑朔迷离。
论文以配套1000MW等级超超临界汽轮发电机组的22.5MW驱动锅炉给水泵汽轮机为研究对象;针对机组“功率高、推力大、转速范围广”的特性及开发难点,对其高速转子轴向推力和动态特性进行了计算和研究分析;缓解了转子轴向推力、临界转速方面互相影响、互相制约的矛盾;证明了单流式设计仍然适用于22.5MW给水泵汽轮机,保证其安全、稳定、高效地运行。
The rotor is one of the most important part of steam turbine. The reliability of unit mostly depend on it. In the design of general rotor of steam turbine, the axial thrust force and other dynamic character are usually within designer’s concern. While designing BFPT, the changing speed brings great challenges.
With the rapidly development of 1000MW extra supercritical pressure units in China, which have obvious advantages of high-efficiency, saving-energy and low-pollution, the demand of matched 22.5MW BFPT is becoming bigger and bigger. It is important to prepare a reliable and efficient 22.5MW BFPT for the market.
However, due to the great output of the 22.5MW BFPT, huge axial thrust force of rotor can hardly be balanced. If the double-flow design is taken, the costs of turbine manufacture and plant construction will highly rise with no advantages in marketing competition. On the other hand, due to the large scale of rotor rated speed, it is difficult to make the critical speed far away from rated speed. The measure to adjust critical speed will change the axial thrust force of rotor at the same time. A delicate circumstance has to be faced while designing the rotor of 22.5MW BFPT.
This research is made for 22.5MW BFPT for 1000MW extra supercritical pressure power plant. Considering the great output, huge axial thrust force and large scale of speed of the rotor, calculations and analysis are made to investigate the axial thrust force and the dynamic character of the high speed rotor. The conflict between the axial thrust force and the critical speed is well solved. It is proved that the design of single casing and single flow is still suitable to 22.5MW BFPT. The security, stability and high efficiency of this BFPT can be guaranteed.
引文
[1]钟一谔,何衍宗,王正等,转子动力学[M],北京:清华大学出版社,1987
[2]顾家柳等,转子动力学[M],北京:国防工业出版社,1985
[3]Nelson H D, McVaugh J M. The dynamics of rotor-bearing system using finite elements[J]. Engrg. For Industry. 1976, 98(2): 593-601
[4]Prohl M A. A general method for calculating critical speeds of flexible rotors[J]. Appl. Mech. Trans ASME 1945, 12(3): 142-148
[5]Myklestad N O. A new method for calculating natural modes of uncoupled bending vibration of airplane wings and other types of beams[J]. Aero. Sci. 1944,11: 153-162
[6]Lund J W. Stability and damped critical speeds of a flexible rotor in fluid flim bearings[J]. Eng for Industry Trans ASME 1974, 96(2): 501-520
[7]谷口修主编,尹传家译,振动工程大全(上册)[M],北京:机械工业出版社,1983
[8]Pilkey W D, Chang P Y.焦宝仁译,静力学和动力学的现代公式[M],北京:中国农业机械出版社,1984
[9]Pestal E C, Leskie F A. Matrix method in Elasto-Mechanics[M]. New York: McGraw-Hill, 1967
[10]Horner G C, Pilkey W D. The Riccati transfer matrix method[J]. Mech. Design Trans ASME 1978, 100(4): 297-302
[11]王正,Riccati传递矩阵法的奇点及其消除方法,振动与冲击[J],1987(2):74-78
[12]丘玉圃,FORTRAN程序设计[M],北京:科学出版社,1979
[13]Murphy B T, Vance J M. An improved method for calculating critical speeds androtordynamics stability of turbomachinery[J]. Eng. For Power Trans ASME 1983, 105(3): 591-595
[14]陆颂元,转子系统阻尼固有频率的传递矩阵-多项式计算法[J],应用力学学报,1986,3(1):73-82
[15]王正,大型转子-轴承-基础系统振动的计算方法[J],清华大学学报,1984,24(1):9-20
[16]黄太平,转子动力学中传递矩阵阻抗耦合法[J],航空动力学报,1988,3(4):315-318
[17]黄太平,多转子系统振动的子系统分析方法-阻抗耦合法与分振型综合法[J],振动工程学报,1988,3(1):30-40
[18]顾家柳,传递矩阵直接积分法及其应用[J],航空学报,1983,4(4):48-56
[19]刘保国等,转子动力学系统的灵敏度分析与动力学修改[J],机械强度,2001,23(1):95-97
[20]杨光等,高速转子的动力学研究[J],武汉理工大学学报,2002,24(2),119-121
[21]田伟华,配超临界600MW等级电站用13.5MW给水泵汽轮机的设计与开发[J],热力透平,2007,36(4),229-232
[2]顾家柳等,转子动力学[M],北京:国防工业出版社,1985
[3]Nelson H D, McVaugh J M. The dynamics of rotor-bearing system using finite elements[J]. Engrg. For Industry. 1976, 98(2): 593-601
[4]Prohl M A. A general method for calculating critical speeds of flexible rotors[J]. Appl. Mech. Trans ASME 1945, 12(3): 142-148
[5]Myklestad N O. A new method for calculating natural modes of uncoupled bending vibration of airplane wings and other types of beams[J]. Aero. Sci. 1944,11: 153-162
[6]Lund J W. Stability and damped critical speeds of a flexible rotor in fluid flim bearings[J]. Eng for Industry Trans ASME 1974, 96(2): 501-520
[7]谷口修主编,尹传家译,振动工程大全(上册)[M],北京:机械工业出版社,1983
[8]Pilkey W D, Chang P Y.焦宝仁译,静力学和动力学的现代公式[M],北京:中国农业机械出版社,1984
[9]Pestal E C, Leskie F A. Matrix method in Elasto-Mechanics[M]. New York: McGraw-Hill, 1967
[10]Horner G C, Pilkey W D. The Riccati transfer matrix method[J]. Mech. Design Trans ASME 1978, 100(4): 297-302
[11]王正,Riccati传递矩阵法的奇点及其消除方法,振动与冲击[J],1987(2):74-78
[12]丘玉圃,FORTRAN程序设计[M],北京:科学出版社,1979
[13]Murphy B T, Vance J M. An improved method for calculating critical speeds androtordynamics stability of turbomachinery[J]. Eng. For Power Trans ASME 1983, 105(3): 591-595
[14]陆颂元,转子系统阻尼固有频率的传递矩阵-多项式计算法[J],应用力学学报,1986,3(1):73-82
[15]王正,大型转子-轴承-基础系统振动的计算方法[J],清华大学学报,1984,24(1):9-20
[16]黄太平,转子动力学中传递矩阵阻抗耦合法[J],航空动力学报,1988,3(4):315-318
[17]黄太平,多转子系统振动的子系统分析方法-阻抗耦合法与分振型综合法[J],振动工程学报,1988,3(1):30-40
[18]顾家柳,传递矩阵直接积分法及其应用[J],航空学报,1983,4(4):48-56
[19]刘保国等,转子动力学系统的灵敏度分析与动力学修改[J],机械强度,2001,23(1):95-97
[20]杨光等,高速转子的动力学研究[J],武汉理工大学学报,2002,24(2),119-121
[21]田伟华,配超临界600MW等级电站用13.5MW给水泵汽轮机的设计与开发[J],热力透平,2007,36(4),229-232