HELIOS2: Benchmarking Against Experiments for Hexagonal and Square Lattices
19th Symposium of AER on VVER Reactor Physics and Reactor Safety (2009, Varna, Bulgaria)
Spectral and Core Calculations
HELIOS2, is a 2D transport theory program for fuel burnup and gamma-flux calculation.
It solves the neutron and gamma transport equations in a general, two-dimensional geometry
bounded by a polygon of straight lines. The applied transport solver may be chosen between:
The Method of Collision Probabilities (CP) and The Method of Characteristics(MoC). The
former is well known for its successful application for preparation of cross section data banks
for 3D simulators for all types lattices for WWERs, PWRs, BWRs, AGRs, RBMK and
CANDU reactors. The later, MoC, helps in the areas where the requirements of CP for computational power become too large of practical application.
The application of HELIOS2 and The Method of Characteristics for some large from calculation point of view benchmarks is presented in this paper. The analysis combines comparisons to measured data from the Hungarian ZR-6 reactor and JAERI?s facility of Tanktype
Critical Assembly (TCA) to verify and validate HELIOS2 and MOC for WWER assembly
imitators; configurations with different absorber types- ZrB2, B4C, Eu2O3 and Gd2O3; and
critical configurations with stainless steel in the reflector. Core eigenvalues and reaction rates
are compared. With the account for the uncertainties the results are generally excellent.
Special place in this paper is given to the effect of Iron-made radial reflector. Comparisons to measurements from TIC and TCA for stainless steel and Iron reflected cores are presented. The calculated by HELIOS-2 reactivity effect is in very good agreement with the
KEYWORDS: HELIOS2, ENDF/B-VII, method of characteristics, benchmarking,WWER1000, Iron reflector.