Simulations of Molten Zircaloy/Pressure Tube Contact Experiments Using Computer Codes WALL25 and MINI-SMARTT-11

Abstract

An experimental program has been initiated to investigate the thermal-mechanical behaviour of a fuel channel when molten Zircaloy (Zr-4) from a fuel bundle flows onto a ballooned pressure tube. Eleven experiments were conducted to date, with various initial conditions .ie., internal pressure of 1 to 5 MPa, water subcooling of 18 to 26 degrees C, and Zr-4 melt of 19 to 88 g. In seven of these experiment, there were small deformations on the calandria tube located beneath the Zr-4 melt but they did not threaten the integrity of the fuel channel. This paper presents the results porn these tests and some simulations results from computer codes WALL23 and MINI-SMARTT-II.