2504 Investigation of Mass Transfer Model for Flow Accelerated Corrosion
Details
Flow Accelerated Corrosion (FAC) requires considerable attention in plant piping management, for its potential of catastrophic pipe rupture of main piping systems. In view of fluid dynamics, the most essential factor to be considered is mass transfer at the inner surface of the pipe. Mass transfer coefficients are determined by fluid properties and piping geometry, however, no universal correlation exists, which is adaptable to various types of piping elements with strong turbulence. In this study, 4 models of mass transfer coefficient was derived based on Chilton-Colburn analogy and utilizing "Effective Friction velocity" from the hydraulics in the viscous sub-layer along the wall. FAC experiments with PWR condensate water condition and CFD for the flow were conducted with a contracted rectangular duct. By comparing the 4 models, verified with the experiments and calculations, the appropriate way of considering friction velocity and turbulent velocity into the mass transfer coefficient was found.
