Modelling CANDU fuel element and bundle behaviour for performance of intact and defective fuel

The FORCE code simulates fuel element performance. Temperature, gas pressure, and sheath strain predictions in an intact element are consistent with the ELESTRES and ELESIM codes. Defective fuel performance predictions show reasonable agreement with coulometric titration fuel stoichiometry data and coolant activity concentration measurements from CRL experiments. A bundle deformation model, assuming a beam element, accurately reproduces verification cases which characterize the BOW code. The addition of endplate interaction is used to simulate an out-reactor deformation experiment conducted by AECL with reasonable agreement. A pellet deformation model demonstrates a capability to analyze pellet-to-pellet and pellet-sheath interaction within an intact element. (author)