LIFE-1, Stress Analysis Swelling and Performance of Cylindrical Fuel Elements in Fast Reactors

1 - Nature of physical problem solved: LIFE1 is designed to predict the in-pile behaviour of cylindrical fast reactor fuel elements. Assuming axial symmetry, the generalized plane-strain analysis combines models for fuel restructuring, migration of fuel constituents, fuel swelling due to accumulation of fission products, fission gas release, hot pressing of the fuel, and clad swelling due to void nucleation and growth. An iterative procedure allows the code to compute the detailed thermal and mechanical response of the fuel element during any specified history of normal reactor power cycling. Up to 10 axial sections are allowed to account for variations in power and coolant temperature, and an option is included for treatment of encapsulated elements. 2 - Restrictions on the complexity of the problem: Up to ten axial sections are allowed to account for axial variations in the power and coolant temperature. In the heat transfer calculations, the fuel and clad may be divided up into arbitrary (user-specified) numbers of equal mass radial sections. In the stress-strain- swelling calculations the fuel is divided into three concentric regions and the clad is a single region. The materials proper- ties, temperatures, stresses, and deformations are averaged over each of these structural regions for the stress calculations