Finite Element Modelling to Investigate the Mechanisms of CRUD Deposition in PWR

  • Jiejie WuEmail author
  • Nicholas Stevens
  • Fabio Scenini
  • Brian Connolly
  • Andy Banks
  • Andrew Powell
  • Lara-Jane Pegg
Conference paper
Part of the The Minerals, Metals & Materials Series book series (MMMS)


Corrosion Related Unidentified Deposition (CRUD) in PWR may cause severe issues, such as Tube Support Plate (TSP) blockage, fuel cladding cracking, and subsequently increased radiation doses for workers. The primary objective of this work is to develop an all-inclusive deposition model, which will reproduce the morphology and elucidate the contributing electrokinetic mechanisms. In this paper the development and verification of a model of the streaming current linking the potential distribution and the fluid flow behaviour using the Finite Element Method (FEM) is presented. In the model, coupled anodic and cathodic regions were found at the inlet of a pipe restriction, associated with a region of recirculating flow following the front facing step (FFS). The corresponding current densities and overpotential at the metal/solution interface were calculated. The coupled anode and cathode may explain the observed deposition process—generating deposits at the front facing step first, followed by a region free of deposits and then repeating ripples of deposited material. At the restriction outlet, a cathode was found which balances the current loops. In this paper, the simulated initiation and propagation processes of the electrokinetic deposition are presented.


CRUD Electrokinetic deposition Streaming currents Multi-physics modelling Finite element method 


  1. 1.
    R.A. Castelli, Nuclear Corrosion Modelling (Oxford: Butterworth-Heinemann, an imprint of Elsevier, 2009), xi–xviiCrossRefGoogle Scholar
  2. 2.
    EPRI, Characterization of PWR steam generator deposits, (Report EPRI TR-106048, Dominion Engineering, INC., McLean, Virginia, 1996)Google Scholar
  3. 3.
    IAEA, Current trends in nuclear fuel for power reactors—NTR supplement (Information document from 51st IAEA General Conference, Austria Center Vienna, Bruno-Kreisky-Platz, Vienna, 17 September 2007), 11Google Scholar
  4. 4.
    M. Guillodo et al., Formation of deposits in HT water under high velocity conditions : a parametric study (Paper presented at the Water Chemistry of Nuclear Reactor Systems Conference, San Francisco, California, 2004), 1941–1949Google Scholar
  5. 5.
    S. Odar, P. Rudling, Crud in PWR/VVER coolant Volume I—sources, transportation in coolant, fuel deposition and radiation build-up (Report LCC10 STR, ANT International, 2014)Google Scholar
  6. 6.
    M. Vepsalainen, T. Saario, Magnetite dissolution and deposition in NPP secondary circuit (Report VTT-R-09735-10, VTT, 2010)Google Scholar
  7. 7.
    C. Brun et al., Investigation on the relation between pressure drops and fluid chemical treatment (Paper presented at the Water Chemistry of Nuclear Reactor Systems Conference, Avignon, France, 2002)Google Scholar
  8. 8.
    M. Guillodo et al., Singular deposit formation in PWR due to electrokinetic phenomena—application to SG clogging (Paper presented at the 6th CNS International Steam Generator Conference, Toronto, Ontario, Canada, 2009)Google Scholar
  9. 9.
    J. Robertson, Corrosion and deposition due to electrokinetic currents (Report TPRD/L/3030/R86, CEGB, 1986)Google Scholar
  10. 10.
    I.S. Woolsey et al., Occurrence and prevention of enhanced oxide deposition in boiler flow control orifices (Paper presented at the water chemistry of nuclear reactor systems 5, Bournemouth, UK, 1989)Google Scholar
  11. 11.
    F. Scenini et al., Electro deposition of CRUD (Report R115529, University of Manchester, 2014)Google Scholar
  12. 12.
    F. Scenini et al., Investigation of the role of electrokinetic effects in corrosion deposit formation. Corros. Sci. 87, 71–79 (2014)CrossRefGoogle Scholar
  13. 13.
    F. Scenini et al., Electrochemical and direct build up measurements of oxide deposition in accelerated flow (Paper presented at the 20th NPC Conference, Brighton, UK, 2016)Google Scholar
  14. 14.
    M. Guillodo et al., Experimental and numerical study of deposit formation in secondary side SG TSP by electrokinetic approach (Paper presented at the Nuclear Plant Chemistry Conference, Paris, France, 2012), 1–14Google Scholar
  15. 15.
    C.W. Turner, M. Godin, Mechanisms of magnetite deposition in pressurized boiling and non-boiling water, (Report AECL-11046, Atomic Energy of Canada Limited Research, 1994)Google Scholar
  16. 16.
    C. Henry, J.P. Minier, G. Lefèvre, Towards a description of particulate fouling: from single particle deposition to clogging. Adv. Colloid Interface Sci. 185–186, 34–76 (2012)CrossRefGoogle Scholar
  17. 17.
    C. Brett, M. Brett, Electrochemistry—Principles, Methods and Applications (Oxford University Press, Oxford, UK, 1993), pp. 39–68Google Scholar
  18. 18.
    J. Bockris, A. Reddy, Modern Electrochemistry 2 (Plenum Press, New York, NY, 1977), pp. 718–790CrossRefGoogle Scholar
  19. 19.
    D. Pletcher, A First Course in Electrode Process, 2nd edn. (The Royal Society of Chemistry, Cambridge, 2009), pp. 1–47Google Scholar
  20. 20.
    A. Banks, A. Powell, L. Pegg, University of Birmingham, Continuum Blue, Rolls-Royce COMSOL Modelling (A talk presented in a meeting in University of Birmingham, 11 December 2014)Google Scholar
  21. 21.
    D. Li, Electro-viscous effects on pressure-driven liquid flow in microchannels. Colloids Surf. A Physicochem. Eng. Asp. 195, 35–57 (2001)CrossRefGoogle Scholar
  22. 22.
    K. Bohinc, V. Kralj-Iglič, A. Iglič, Thickness of electrical double layer. Effect of ion size. Electrochim. Acta 46, 3033–3040 (2001)CrossRefGoogle Scholar
  23. 23.
    E. Bardal, Corrosion and Protection (USA: Springer-Verlag London, 2004), 35–51Google Scholar

Copyright information

© The Minerals, Metals & Materials Society 2019

Authors and Affiliations

  • Jiejie Wu
    • 1
    Email author
  • Nicholas Stevens
    • 1
  • Fabio Scenini
    • 1
  • Brian Connolly
    • 1
  • Andy Banks
    • 2
  • Andrew Powell
    • 2
  • Lara-Jane Pegg
    • 2
  1. 1.The University of ManchesterManchesterUK
  2. 2.Rolls-Royce PlcManchesterUK

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