Browse > Article
http://dx.doi.org/10.3795/KSME-A.2015.39.7.713

Fatigue Damage Analysis of a Low-Pressure Turbine Blade  

Youn, Hee Chul (Dept. of Mechanical Engineering, Incheon Nat'l Univ.)
Woo, Chang Ki (Dept. of Mechanical Engineering, Incheon Nat'l Univ.)
Hwang, Jai Kon (KEPCO Plant Service & Engineering Co., Ltd.)
Publication Information
Transactions of the Korean Society of Mechanical Engineers A / v.39, no.7, 2015 , pp. 713-720 More about this Journal
Abstract
The sizes of the final blades of a low-pressure (LP) steam turbine have been getting larger for the development of high-capacity power plants. They are also larger than the other blades in the same system. As a result, fatigue damage is caused by a large centrifugal force and a low natural frequency of the blade. Recently, many failure cases have been reported due to repeated turbine startups and their prolonged use. In this study, the causes and mechanism of failure of a LP turbine blade were analyzed by using a finite element method to calculate the centrifugal force, the natural frequency of a stress-stiffening effect, and the harmonic response. It was observed that the expected fatigue damage position matched the real crack position at the airfoil's leading edge, and an equivalence fatigue limit approached a notch fatigue limit.
Keywords
Steam Turbine; Blade; Fatigue; Frequency Analysis; Harmonic Response Analysis; Finite Element Method; Notch;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 Song, G. W., Choi, W. S., Kim, W. J. and Jung, N. G., 2013, "Damage Analysis for Last-Stage Blade of Low- Pressure Turbine," Trans. Korean Soc. Mech. Eng. B, Vol. 37, No. 12, pp. 1153-1157.   DOI   ScienceOn
2 Yun, T. j., Kim, D. H., Kim, D. H., Park, L. and Suk, J. I., 2010, "Structural Evaluation and Life Assessment of 5MW Power Generation Gas Turbine Blade," KSME 2010 Spring Annual Meeting, pp. 556-561.
3 Lucjan, Witek., 2011, " Numerical Stress and Crack Initiation Analysis of the Compressor Blades After Foreign Object Damage Subjected to High-cycle Fatigue," Engineering Failure Analysis 18, pp.2111-2125.   DOI   ScienceOn
4 Kim, H. J., and Kang, Y. H., 2010, "Crack Evaluation and Subsequent Solution of the Last Stage Blade in a Low-pressure Steam Turbine," Engineering Failure Analysis 17, pp.1397-1403.   DOI   ScienceOn
5 Wang, W. Z., Xuan, F. Z., Zhu, K. L. and Tu, S.T., 2007, "Failure Analysis of the Final Stage Blade in Steam Turbine," Engineering Failure Analysis 14, pp. 632-641.   DOI   ScienceOn
6 Yoon, K. B., Ma, Y. W., Kim, Y. I., Cha, S. J. and Kim, Y. J., 2005, "Failure Analysis of Gas Turbine Compressor Blades," KSME 2005 Spring Annual Meeting, pp. 185-190.
7 Hou, J., Wicks, B. J. and Antoniou, R. A., 2002, "An Investigation of Fatigue Failures of Turbine Blades in Gas Turbine Engine by Mechanical Analysis," Engineering Failure Analysis 9, pp. 201-211.   DOI   ScienceOn
8 Yoo, K. B., Hyun, J. S., Song, G. W. and Kim, J. H., 1999, "Life Evaluation and Nondestructive Diagnosis of Low-Pressure Turbine Blade for Nuclear Power Plant," KSME 1999 Spring Annual Meeting, pp. 913-918.
9 Kattus, J. R., 1973, Aerospace Structural Metal Handbook, Vol. 2, Code 1403, pp. 1-17.