Ballooning Deformation of Zircaloy-4 Fuel Sheath

In this paper, both experimental and analytical investigations have been conducted to investigate the fuel sheath (also known as clad tube) ballooning deformation and subsequent bursting. The work has been performed to simulate ballooning deformation of fuel sheaths under different heating rates and internal pressures in an inert atmosphere. An experimental setup has been designed to capture the temperature, pressure, and wall displacement data during the ballooning deformation of the sheath specimen. Also, a computer code in MATLAB has been developed to compute the stresses and strains at the ballooning site of the fuel sheath. The developed model has been validated with present and past experimental studies. A parametric study has also been conducted to study the effect of internal pressure, heating rate, and sheath dimensions on hoop or circumferential strain.