Analysis of the Leakage-Flow-Induced Vibration of a Slip Joint in a Jet Pump of a Boiling Water Reactor

Abstract:

The purpose of this analysis is to evaluate the structural integrity of the jet pump assembly of a BWR during the performance of its operational and safety functions. The natural frequencies and vibration modes of the jet pump assembly immersed in water were determined. It was observed that the fourth mode shape was torsional, and its associated resonance frequency was 41.82 Hz. Also, the vibration induced by the flow in the leakage of the slip joint was analyzed with an axisymmetric model. The gap of the slip joint was varied from 0.2 mm until 0.65bmm. A gap between 0.6 and 0.64, would cause flow-induced vibration because this excitation frequency matches with the fourth natural frequency of the jet pump assembly. The above was carried out using computational fluid dynamics, as well as the finite element method, with ANSYS Structural and ANSYS Fluent codes.

• Periodical: Defect and Diffusion Forum (Volume 390)
• Pages: 23-31
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.390.23
• Online since: January 2019
• Authors: Juan Cruz Castro*, E. Hernández Palafox, I.A. Alarcón Sánchez, Luis Héctor Hernández-Gómez, Pablo Ruiz-López, A. Armenta Molina
• Keywords: ACT Acoustic, ANSYS Fluent, BWR5, In-Water Natural Frequencies, Vibration Induced by Axial Flow

References

[1] International Atomic Energy Agency, IAEA-TECDOC-1471, Assessment and Management of Ageing of Major Nuclear Power Plant Components Important to Safety: BWR Pressure Vessel Internals, USA: IAEA, October (2005).

[2] United States Nuclear Regulatory Commission, Technical Training Center, BWR/4 Technology Manual (R-104B), USA: USNRC.

[3] F. L. L. Chi, Jet Pump with labyrinth seal,. USA Patent 4,285,770, 25 agosto (1981).

[4] M. P. Païdoussis, Annular and Leakage-Flow-Induced Instabilities,, in Fluid-Structure Interactions. Slender Structures and Axial Flow. Vol. 2, Canada, Academic press, 2016, pp.643-769.

DOI: 10.1016/b978-0-12-397333-7.00007-3

[5] D.S. Weaver, et al., Flow-Induced Vibrations in Power and Process Plant Components. Progress and Prospects,, Journal of Pressure Vessel Technology, vol. 122, pp.339-348, (2000).

DOI: 10.1115/1.556190

[6] S.-S. Chen, Introduction,, in Flow-induced vibration of circular cylindrical structures, USA, Argonne National Laboratory, 1985, pp.1-3.

[7] B. Carter, Jet Pump Degradation Management,, 2010. [Online]. Available: https://www.nrc.gov/docs/ML1015/ML101590703.pdf. [Accessed 07 mayo 2018].

[8] M. Watanabe, et al., Improvement of jet pump inlet mixer in Boiling Water Reactor for mitigating flow-induced vibration and fouling,, in Proceedings of the ASME 2013 Pressure Vessels and Piping Conference, Paris, France, (2013).

DOI: 10.1115/pvp2013-97235

[9] M. Watanabe, K. Kinugasa, H. Adachi, H. Mori, Flow-induced vibration suppression of jet pump in Boiling Water Reactor by slip joint extension,, in Proceedings of the 2014 22nd International Conference on Nuclear Engineering, Prague, Czech Republic, (2014).

DOI: 10.1115/icone22-30700

[10] The American Society of Mechanical Engineers, Section III, Rules for Construction of Nuclear Facility Components, The ASME Boiler and Pressure Vessel Code, USA: ASME, (2004).

[11] F. Inada, A study on Leakage Flow Induced Vibration from engineering viewpoint.,, in Proceedings of the ASME 2015 Pressure Vessels and Piping Conference, USA, (2015).

[12] T. M. Mulcahy, Leakage-Flow-Induced Vibrations of reactor components,, Argone National Laboratory, USA, (1983).

[13] R. D. Blevins, Formulas for Natural Frecuency and Mode Shape, USA: Van Nostrand Reinhold, 1979, pp.386-422.

[14] R. D. Blevins, Flow-Induced Vibration,, USA, Krieger Publishing, 1990, pp.1-4.

[15] G. L. Stevens, R. A. Mattson, D. M. Swann, Jet pump flaw evaluation procedures,, in Proceedings of ICONE. 8th International Conference on Nuclear Engineering, Baltimore, USA, april 2000, pp.1-8.

[16] Cuahquentzi, N. M., et al., Evaluation of the Structural Integrity of the Jet Pumps of a Boiling Water Reactor under Hydrodynamic Loading,, in Defect and Diffusion Forum, vol. 348, Switzerland, Trans Tech Publications, 2014, pp.261-270.

DOI: 10.4028/www.scientific.net/ddf.348.261

[17] ANSYS, appstore ansys,, 2018. [Online]. Available: https://appstore.ansys.com/shop/ ACTApps_act%20apps. [Accessed 30 Enero 2018].

[18] C. Q. Howard, Acoustic Analyses Using MATLAB and ANSYS, USA: CRC Press, (2015).

[19] ANSYS, Workshop 09 Fluent Introduction,, in Customer Training Material, USA, ANSYS, 2016, p.14.

[20] ANSYS, Lecture 10 Fluent Introduction,, in Customer Training Material, USA, ANSYS, 2016, p.9.