Calculations of VVER‐1000 Start‐Up Physics Tests Using the MCU Monte Carlo Code
26th Symposium of AER on VVER Reactor Physics and Reactor Safety (2016, Helsinki, Finland)
Reactor physics experiments and code validation continues
Abstract
CALCULATIONS OF VVER-1000 START-UP PHYSICS TESTS USING THE MCU MONTE CARLO CODEA.S. Bikeev, M.A. Kalugin, D.A. Shkarovsky, Anna I. Shcherenko, A.A. Pinegin, D.V. AfanasevNRC “Kurchatov Institute”, 123182, Russia, Moscow, Kurchatova sq., 1ABSTRACTCalculations of start-up physics tests for the unit 3 of Rostov NPP were carried out using the MCU Monte Carlo code.For calculations of start-up tests, a full-scale computer model of VVER-1000 was developed using the design documentation for fuel assemblies and a reactor facility: reports, blueprints, explanatory notes, and technical validations. The model consists of a core, a base plate, a baffle, a reactor pit, a reactor vessel, and beyond vessel space, including a dry protection, a concrete shaft, a support girder, a biological protection. The reactor core was assembled from 163 fuel assemblies with fresh fuel, according to the pattern of the load 1 of the unit 3 of Rostov NPP. The special attention was given to the accuracy of the geometry and material description of fuel and control rods, spacer and mixing grids, thimble tubes, bottom and top nozzles during the FA model development. The model of a fuel rod consists of a cladding, fuel pellets, a spring lock, and top and bottom end-pieces.Precision calculations of the following neutron physical characteristics were carried out: the boric acid concentration in coolant for all critical conditions of the core, the efficiency of single control rods, the integral and differential efficiency of the RCCA groups, the efficiency of the emergency protection and the reactivity coefficients.The comparative analysis was made for the calculated and experimental values. As a result, adequate deviations were attained.26th Symposium of AER on VVER Reactor Physics and Reactor Safety 18 10 – 14 October 2016, Helsinki, Finland