Experiments to Determine the Thermal-Mechanical Response when Molten Zircaloy-4 Flows onto a Ballooned Pressure Tube

Abstract

An experimental program has been set up to investigate the thermal-mechanical behaviour of a fuel channel when molten Zircaloy-4 (Zr-4) from a fuel bundle flows onto a ballooned pressure tube. The first two tests of the series were carried out with a pressure of 3 MPa inside the pressure tube and subcooling on the calandria tube of about 20 degrees C. Results show that the calandria tube dries out directly under the Zr-4 melt but quickly rewets within 22 s. The maximum calandria tube temperature measured directly under the molten Zr-4 droplet was 900 degrees C. This paper describes the experimental setup and summarizes results from these first two tests.