The “reactor simulator” program for simulating load-tracking states in a vvér-1000 reactor

Abstract

Currently operated VVI~R-1000 reactors operate in base-load support, and their standard data-acquisition and computing systems are designed in the main to maintain a steady state in the reactors. However, there are often deviations from base load operation, and a reactor may operate in a transient state several times during a run, which requires management in states far from equilibrium. Also, new designs for nuclear stations containing VVER-1000 envisage load following on the daily power graph.The operator should thus provide optimum management over conditions more complicated than base load ones, which requires appropriate data support. Such facilities have been incorporated at foreign nuclear power stations such as the BEACON system produced by Westinghouse [1].The need for similar systems for VV~R stations is reflected in the requirements of the state standard. For example, according to GOST R 50088-92 for VVI~R stations, when the reactor operates in the transient state, there should be provision for calculating the current state and forecasting its behavior, and also support to the operator to choose the optimum management.The "reactor simulator" program has been written for simulating load-following modes of Wt~R-1000 reactors. The first version is available, which does not require direct installation in the nuclear station. Instead, it is used off-line for examining load-following WI~R-1000 states and also for analyzing typical situations and for forecasting planned load following at nuclear stations.The functions of the "reactor simulator" program are briefly as follows. General Information. The program is a universal means of simulating the VVI~R-1000 in nonstationary states and is intended for forecasting in managing stations and also for use in design and research to improve fuel cycles and reactor management algorithms. Fortran-95 is used. The program works efficiently on personal computers of PC-AT/486 class or above.Reactor Model. Tile part dealing with the neutron physics (with a two-group diffusion model) and with the accumulation of wastes and the variations in t35Xe and 149Sm concentrations is the same as that in the BIPR-7 program [2]. The xenon kinetics are simulated together with calculations on the nonstationary 149Sm concentration and the fuel burn-up. In initiation and forecasting modes, one considers the nonequilibrium 135Xe concentration, while one considers the equilibrium one in load burn-up and archive translation modes.A major feature of the program is that the working control rod groups can occupy any positions, not merely ones that are multiples of the height step in the net used in the BIPR-7, and this is attained by use of a special interpolation for the neutron-physics constants.Basic Functions. The program implements the following basic functions: 1) calculations on reactor states and nonequilibrium fuel burn-up and 149Sm and 135Xe concentrations; 2) calculating the linear fuel pin power; 3) adjustment to the current state on the basis of the history and forecasting the subsequ...

Investigation of xenon transient processes in VVER-1000 at the Tianwan nuclear power plant (China)

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A method for limitation of probability of accumulation of fuel elements claddings damage in WWER

“…Учитывая амплитуду перемещения органов регулирования, необходимую для стабильности аксиального офсета, используя программные средства "Имитатор реактора" [7] и FEMAXI [8], ЭВТП-критерий при A 0 = 30 MДж/м 3…”

Adoption of Improved Algorithms for Controlling the Energy Release of a VVER-1000 Core at the Khmel’nitskii Nuclear Power Plant

“…An additional computational module RS (reactor simulator) [4] is added to the in-reactor monitoring system (SVRK-M) [4]. As a result, additional functions of information support for the operator are implemented.…”