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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)

Abstract

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.

Keywords

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

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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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