METHOD AND SYSTEM TO DETECT AND LOCATE THE IN-CORE POSITION OF FUEL BUNDLES WITH CLADDING PERFORATIONS IN CANDU-STYLE NUCLEAR REACTORS

摘要

A method for detecting a leak in a cladding tube in a nuclear reactor is described. The method is well-suited for use in a reactor having a plurality of cladding tubes housed in a plurality of linearly arranged channels for flowing coolant past the cladding tubes. The method includes monitoring the channels for the occurrence of an increase in radiation above a selected base line indicative of the presence of at least one fission product in the coolant in at least one of the plurality of channels, and monitoring the channels for the occurrence of time dependent changes in the strength of radiation in the coolant above the base line along the length of the at least one of the plurality of channels. The leak location is calculated by triangulating the radiation readings from a fixed linear array of detectors positioned adjacent to the channels to determine the location of the strongest radiation reading and the location along the length of the channel where the increase in radiation occurred.