Finite Element Modeling of Eddy Current Probes for CANDU® Fuel Channel Inspection

M. S. Luloff [1], T. W. Krause [2], J. Morelli [1],
[1] Queen's University, Kingston, ON, Canada
[2] Royal Military College of Canada, Kingston, ON, Canada
发布日期 2015

CANDU® reactor pressure tubes (PT) contain D2O, which is used as a moderator. Surrounding the PTs are gas-filled Calandria Tubes (CT), which thermally isolate the PTs from the moderator surrounding the fuel channels. If the garter springs move apart, the PT will sag into the CT. Under contact conditions, the thermal gradient between the hot PT and cold CT accelerates the ingress of deuterium into the PT. This accumulated deuterium reduces the fracture toughness of the material. Eddy current testing is used for in-reactor inspection, however variations in probe liftoff, material resistivity and wall thickness affect the response. Therefore, a rigorous understanding of these phenomena is required to improve the accuracy of the EC instrument, and this is being done using COMSOL Multiphysics® software.