Browse > Article

Shell Wall Thinning and Mitigation Plan and Design Modification of a Feedwater Heater Impingement Baffle  

Kim, Kyung-Hoon (Department of Mechanical Engineering, KyungHee Univ.)
Hwang, Kyeong-Mo (Korea Power Engineering Co. Inc.)
Park, Sang-Hoon (Graduate school, KyungHee Univ.)
Publication Information
Abstract
Feedwater heaters of many nuclear power plants have recently experienced severe wall thinning damage, which will increase as operating time progresses. Several nuclear power plants in Korea have experienced wall thinning damage in the area around the impingement baffle inside feedwater heater installed downstream of the turbine extraction stream line. At that point, the extract steam from the turbine is two phase fluid at high temperature, high pressure, and high speed. Since it flows to reverse direction after impinging the impingement baffle, the shell wall of feedwater heaters may be affected by flow-accelerated corrosion. In this paper, to compare degree of shell wall thinning mitigation rate to squared type with mitigation rate of other type baffle plate, three different types of impingement baffle plate-squared, curved and mitigating type-applied inside the shell. With these comparison data, this paper describes operation of experiments and numerical analysis which is composed similar condition with real feed water heater. And flow visualization is operated for verification of experiments and numerical analysis. In conclusion, this study shows that mitigating type baffle plate is more effective than other baffle plate about prevention of pressure concentration and pressure value decrease.
Keywords
Wall Thinning; Flow-Accelerated Corrosion; Feedwater Heater; Extracting Nozzle; Impingement Baffle;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 Keller, H., "Corrosion and Erosion Problems in Saturated Steam Turbines," AIM Conf., pp. 22-28, 1978.
2 Cengel, Y. A. and Cimbala, J. M., "Fluid Mechanics : Fundamental and Application," McGRAW-HILL, 2006.
3 Kim, K. H., Lee, W. and Hwang, K. M., "A Study on Experiment and Numerical Analysis for Disclosing Shell Wall Thinning of a Feedwater Heater," Transactions of KSME(B), Vol. 31, No. 1, pp. 1-7, 2007.   과학기술학회마을
4 Fluent Inc., "Fluent 6.x Trainning Notes," 2006.
5 Kastner, W. and Riedle, K., "Empirisches Modell zur Berechnung von Materialabtragen durch Erosionskorrosion," VGB Kraftwerkstechnik, Vol. 66, No. 10, pp. 1171-1178, 1986.
6 Potter, M. C. and Scott, E. P., "Thermal Science : An Introduction to Thermodynamics, Fluid Mechanics and Heat Transfer," Thomson Books, 2005.
7 Kim, K. H., Hwang, K. M. and Jin, T. E., "Fluid Mixing Analysis for Predicting Shell Wall Thinning of a Feedwater Heater," J. of Mechanical Science and Technology, Vol. 19, No. 1, pp. 173-180, 2005.   DOI   ScienceOn
8 KHNP, "Technical Review Report for Thickness Verification of Feedwater Heater Shell Side of Kori Unit 1," Kori First Plant, Mechanical Department Report No. 3, 2000.
9 Fort Calhoun, "Shell Wall Thinning of Feedwater Heater," INPO, OE 10710, 1999.
10 Point Beach 1, "Steam Leak From Low Pressure Feedwater Heater," 1999-005, LER, 1999.