Pre-test Simulations of the CHAN 28-Element High-Temperature Thermal-Chemical Experiment Using the Computer Codes CATHENA and CHAN-II-WL

Abstract

Pre-test simulations have been performed for the first out-of-pile 28-element high-temperature thermal-chemical experiment using the computer codes CATHENA (MOD-3.3h) and CHAN-II-WL (MOD-28a). The ongoing CEUN thermal-chemical experimental program at Whiteshell Laboratories provides experimental data on the integrated thermal-chemical transient behaviour of a CANDU fuel channel with low-pressure, single-phase steam as the only coolant inside the channel. The program also increases our understanding of the behaviour of fuel channels at high temperatures and their integrity during postulated accidents. A parametric study was performed using the computer codes to examine effects of steam flow rates, unheated fuel element simulators, moderator temperatures, and other variables on the predicted outcome of the experiment. The results of this study were used to optimize the experimental input parameters and test procedures. This paper details the parametric study with emphasis on the predicted effects of the various steam flow rates on test section behaviour.