Authors & Affiliations
Kulikov V.I.1, Popykin A.I.2, Zhylmaganbetov N.M.2
1 St. Petersburg branch of Joint-stock company Federal centre for science and high technology "Special scientific and production Association "Eleron"-"VNIPIET", Saint Petersbugr, Russia
2 Scientific and Engineering Centre for Nuclear and Radiation Safety, Moscow, Russia
Kulikov V.I. – Head of a Laboratory, Cand. Sci. (Phys. and Math), St. Petersburg branch of Joint-stock company Federal centre for science and high technology "Special scientific and production Association "Eleron"-"VNIPIET".
Popykin A.I. – Head of a Laboratory, Cand. Sci. (Phys.- Math), Scientific and Engineering Centre for Nuclear and Radiation Safety.
There is considered a problem about numerical simulation of measurement of total rod worth by using rod drop method in VVER reactor. Total rod worth is large reactivity so it is much larger than the value of the effective delayed neutron fraction – βef. Rod drop method is described in Kazansky Yu.A., Matusevich E.S. "Experimental Reactor Physics", definitions of measured and calculated reactivities for VVER reactors are presented in RB-074-12. The main assumption is quasi-steady formulation of the problem namely it is considered that the system under consideration changes with the time as a result of the change of concentrations of the delayed neutron precursors and the position of control rods. Reactivity of VVER reactors is measured with the aid of ionization chambers located outside the core. The signal of ionization chambers is processed by reactivity meter using inverse kinetics equations. Measurements are conducted at the minimum controlled power level and ionization chambers current is measured. Drop of control rods is conducted at or about critical state of a reactor. With some additional assumptions, some useful conclusions are followed from the analysis for estimating the components of ρk, error, the correlation between errors of measurements and calculations.
VVER, reactivity, numerical simulation of measurement, ionization chamber, emergency protection, control rods, simulation, comparison between results of measurements and calculations, adjoint function
1. Kazansky Yu.A., Matusevich E.S. Experimentalnaya fizika reactorov [Experimental Reactor Physics]. Moscow, Energoatomizdat Publ., 1994. 352 p.
2. Polozhenie o rekomendaciyah po sopostavleniyu rasschitanoy i izmerenoy reactivnosti pri obosnovanii yadernoy bezopasnosti reactornyh ustanovok VVER [Statute of recommendation for comparison calculated and measured reactivity under verification and validation of VVER nuclear safety], RB-074-12.
3. Metodika rasheta neitronno-fizicheskih harakteristik po dannym fizicheskih experimentov na energoblokah atomnyh elektrostanciy c reaktorami VVER-1000 [The method for calculating neutronic parameters from physical experiment data obtained from NPP units with VVER-1000]. RD-EO 0151-2004.
4. Popykin A., Shevchenko S., Shevchenko R., Zhylmaganbetov N., Kulikov V. Problem Formulation of Numerical Reactivity Measurement Simulation. Proc. Int. Conf. "Reactor Physics Topical Meeting", PHYSOR 2016. Sun Valley, Idaho, 2016.
5. Kavun O.Yu. Metodika modelirovaniya dinamiki energobloka AES, realizovanaya v programmnom komplekse RADUGA-EU [Computational models for simulating the dynamics of NPP, implemented in software package RAINBOW]. Voprosy atomnoi nauki i techniki. Seriya: Fizika yadernykh reaktorov – Problems of atomic science and technology. Series: Physics of Nuclear Reactors, 1999, no. 2, pp. 16-23.
6. Tereshonok V.A., Kryakvin L.V., Pitilimov V.A., Karpov S.A., Kulikov V.I., Zhylmaganbetov N.M., Kavun O.Yu., Popykin A.I., Shevchenko R.A., Shevchenko S.A., Semenova T.V. Raschetnoe modelirovanie izmereniy na etape fizicheskogo puska energobloka no. 3 Rostovskoy AES [Numerical simulation of measurements of a physical start-up of unit 3 Rostov NPP]. Voprosy atomnoi nauki i techniki. Seriya: Fizika yadernykh reaktorov – Problems of atomic science and technology. Series: Physics of Nuclear Reactors, 2015, no. 6, pp. 62-71.