Mechanism Study and Numerical Simulation on Blistering of Plate-Type Fuel Available to Purchase

In this paper, the occurrence mechanism of blistering was studied and development processes of blistering were summarized. In addition, a thermal-mechanic-material coupling analysis code, named FROBA-PLATEs (Fuel Rod Behavior Analysis for PLATEs), was developed for plate-type fuel with the consideration of burnup effect. FROBA-PLATEs code was applied to perform the behavior analysis of a dispersion-plate-type fuel. Significant phenomena, including fission gas release and matrix damage, were simulated and key parameters, such as temperature profile, stress and strain profile, were obtained. Most important of all, the starting time of blistering was gained according to the deformation of cladding. The result indicates that: blistering happened at high burnup stage; power density and thickness of cladding are sensitive parameters for blistering. Reducing the power density or enlarge the thickness of cladding can delay or prevent blistering. Furthermore, the influence of blistering on thermal-hydraulic performance was preliminarily investigated by CFD simulation. The simulation result indicates that blistering results in deterioration of heat conduction in the fuel plate.