Evaluation of Rod and Assembly Bowing Effect on Rod-Wise Fission Powers Using Serpent and CASMO-4E
25th Symposium of AER on VVER Reactor Physics and Reactor Safety (2015, Balatongyörök, Hungary)
Advances in spectral and core calculation methods
Abstract
The impact of rod and assembly bowing on rod-wise fission powers was studied using the
Monte Carlo reactor physics code Serpent and the 2D lattice code CASMO-4E. The rod
bowing was simulated with Serpent by changing the positioning of the fuel pins. In other
words, the simulations were carried out in an irregular pin lattice. The effect of assembly
bowing was studied with CASMO-4E by changing the water gap size between the assemblies.
In both Serpent and CASMO-4E analyses, the considered deviations were chosen in a
conservative manner on the basis of pool-side inspections results.