Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
권호 표지

KAIST-CIWH Computer Code and a Guide Chart to Avoid Condensation-Induced Water Hammer in Horizontal Pipes

  • Chun, Moon-Hyun (Korea Advanced Institute of Science and Technology) ;
  • Yu, Seon-Oh (Korea Advanced Institute of Science and Technology)
  • Published : 2000.12.01
Download PDF
⟨ Previous Next ⟩

Abstract

A total of 17 experimental data for the onset of slugging, which is assumed to be the precursor of the condensation-induced waterhammer (CIWH), have been obtained for various How rates of water Incorporating the most recent correlations of interfacial heat transfer and friction factor developed for a circular geometry and using an improved criterion of transition from stratified to a slug flow, two existing analytical models to predict lower and upper bounds for CIWH have been upgraded. Applicability of the present as well as existing CIWH models has been tested by comparison with two sets of CIWH data. The result of this comparison shows that the applicability of the present as well as existing models is reasonably good. Based on the present models for CIWH, a computer code entitled as“KAIST-CIWH”has been developed and sample guide charts to find CIWH free regions for a given combination of major flow parameters in a long horizontal pipe have been presented along with the results of parametric studies of major parameters (D, P, $T_{f,in}$, and L/D) on the critical inlet water flow rate（$W_{f,in}_crit$ for both lower and upper bounds. In addition, two simple formulas for lower and upper bounds that can be used in an emergency for quick results have been presented.

Keywords

References

  1. Yow, W., Van Duyne, D.A., Chiu, Chong, 1988. Analysis of root causes of water hammer. 3rd Int. Topical Meeting on Nuclear Power Plant Thermal Hydraulics and Operations(NUPTHO-3), A10-103-109
  2. D. A. Van Duyne, W. Yow, and J. W. Sabin, Water Hammer Prevention, Mitigation and Accommodation. EPRI NP-6766, (1992)
  3. J. A. Block, P. H. Rothe, C. J. Crowley, and G. B. Wallis, An Evaluation of PWR Steam Generator Water Hammer, NUREG-0291 (1977)
  4. M. G. Izenson, P. H. Rothe, and G. B. Wallis, Diagnosis of Condensation-Induced Water hammer, NUREG/CR-5220 (1988)
  5. R. W. Bjorge and P. Griffith, 'Initiation of water hammer in horizontal and nearly horizontal pipes containing steam and subcooled water,' ASME J. Heat Transfer, 106, 835-840 (1984)
  6. J. H. Linehan, M. Petrick, and M. M. El-Wakil, 'The condensation of a saturated vapor on a subcooled film during stratified flow,' AIChE Progress Symposium Series, 66, 11-20 (1970)
  7. Y. Taitel and A. E. Dukler, 'A model for predicting flow regime transitions in horizontal and near horizontal gas-liquid flow,' AIChE J., 22, 47-55 (1976) https://doi.org/10.1002/aic.690220105
  8. M. H. Chun and C. K. Sung, 'Onset of slugging criterion based on characteristics and stability analyses of transient one-dimensional two-phase flow equations of two-fluid model,' Int. Comm. Heat Mass Transfer, 23, 473-484 (1996) https://doi.org/10.1016/0735-1933(96)00032-2
  9. I. C. Chu, S. O. Yu, and M. H. Chun, Interfacial condensation heat transfer for countercurrent steam-water stratified flow in a horizontal circular pipe,' First Korea-Japan Symposium on Nuclear Thermal Hydraulic and Safety (NTHAS98), 299-306 (1998)
  10. Chun et al., Development of a Model for Analysis of the Water Hammer in NPP and the Evaluation of Thermo-Hydraulic Design of RCS, Korea Electric Power Research Institute, TR.95ZJ16.J1999.115 (1999)
  11. M. H. Chun and H. Y. Nam, 'Analysis of water hammer induced by steam-water counterflow in a long horizontal pipe,' Int. Comm. Heat Mass Transfer, 19, 507-518 (1992) https://doi.org/10.1016/0735-1933(92)90006-4
  12. C. Chiu, D. Tuttle, and A. W. Serkiz, 'Water hammer in a PWR horizontal feedwater line,' ANS Trans., 52, 589-590 (1986)
  13. Y. Chou and P. Griffith, 'Admitting cold water into steam filled pipes without water hammer due to steam bubble collapse,' Nuclear Engineering and Design, 121, 367-378 (1990) https://doi.org/10.1016/0029-5493(90)90018-S
  14. A. B. Jackobek and P. Griffith, Investigation of Cold Leg Water Hammer in a PWR Due to the Admission of Emergency Core Cooling During a Small Berak LOCA, NUREG/CR-3895, (1984)
  15. L. Breiman and J. H. Friedman, 'Estimating optimal transformations for multiple regresseion and correlation,' J. Am. Stat. Assoc., 80, 580-598 (1985) https://doi.org/10.2307/2288473
  16. G. G. Brucker and E. M. Sparrow, 'Direct contact condensation of steam bubbles in water at high pressure,' Int. J. Heat Mass Transfer, 20, 371-381 (1977) https://doi.org/10.1016/0017-9310(77)90158-2