Simulation of the chernobyl accident

An analysis of the April 26, 1986 accident at the Chernobyl-4 nuclear power plant in the Soviet Union is presented. The peak calculated core power during the accident was 550 000 MW_t. The analysis provides insights that further understanding of the plant behavior during the accident. The plant was modeled with the RELAP5/MOD2 computer code using information available in the open literature. RELAP5/MOD2 is an advanced computer code designed for best-estimate thermal-hydraulic analysis of transients in light water reactors. The Chernobyl-4 model included the reactor kinetics effects of fuel temperature, graphite temperature, core average void fraction, and automatic regulator control rod position. Preliminary calculations indicated the effects of recirculation pump coast down during performance of a test at the plant were not sufficient to initiate a reactor kinetics-driven power excursion. Another mechanism, or “trigger” is required. The accident simulation assumed the trigger was recirculation pump performance degradation caused by the onset of pump cavitation. Fuel disintegration caused by the power excursion probably led to rupture of pressure tubes. To further characterize the response of the Chernobyl-4 plant during severe accidents, simulations of an extended station blackout sequence with failure of all feedwater are also presented. For those simulations, RELAP5/MOD2 and SCDAP/MOD1 (an advanced best-estimate computer code for the prediction of reactor core behavior during a severe accident) were used. The simulations indicated that fuel rod melting was delayed significantly because the graphite acted as a heat sink.     

Method for liquidating the consequences of the chernobyl accident

Conclusions The proposed method is a safe, technically feasible, and economically acceptable solution to the problem of liquidating the focus of the environmental contamination at the Chernobyl nuclear power plant. The radioactive substances, materials, and objects will be removed from “Cover” and imperfect storage sites within the 100-km zone around the Chernobyl nuclear power plant and placed in storage sites which meet modern requirements. The storage of the wastes will be controllable and monitorable. The object “Cover” will be liquidated. Main Scientific Center of the Russian Federation — Physics and Power Engineering Institute. Translated from Atomnaya énergiya, Vol. 78, No. 3, pp. 214–217, March, 1995.     

Analysis of the chernobyl accident taking core destruction into account

Russian Scientific Center Kurchatovskii Institut. Bremen, Germany. Translated from Atomnaya énergiya, Vol. 77, No. 2, pp. 87–93, August, 1994.     

Examination of the destructive forces in the chernobyl accident based on NSRR experiments

The possible causes of the destruction of the Chernobyl reactor core were examined by making use of the Nuclear Safety Research Reactor (NSRR) experimental results concerning the destructive forces generated by a fuel failure. A complementary experiment with Chernobyl reactor conditions was performed in order to observe the fuel failure behavior and the resultant vessel pressure rise, etc. Also, generation of hydrogen from the fuel rod cladding and the consequent system pressure rise were estimated based on the experiments.These examinations led to the conclusion that the most probable cause of the core pressure tube rupture in the accident was a static pressure rise due to rapid energy release from fragmented fuel. Other phenomena such as the hydrogen generation and molten fuel contact to the tube wall might have contributed to the tube rupture. The water hammer force is also estimated to have been large enough to break tubes even using conservative assumptions.     

Health assessment of participants in the liquidation of the consequences of the chernobyl accident

The results of an analysis of the health of the participants in the liquidation of the consequences of the Chernobyl accident on the basis of the mortality indicator for the participants are reported. The computational results obtained for the harm due to mortality using estimation of the loss of life due to premature death are presented. It is shown that the relative risk of these losses for certain classes of diseases and dose groups depends on the social position of the liquidators of the accident. Recommendations are made for improving measures for their medical and social rehabilitation. 1 figure, 6 tables, 20 references. National Science Center of the Russian Federation—Institute of Biophysics. Translated from Atomnaya énergiya, Vol. 86, No. 3, pp. 232–238, March, 1999.     

Contamination of reservoir banks in the Dnieper cascade as a result of the chernobyl accident

Information obtained on the contamination of the banks of the Dnieper cascade in expeditionary surveys during 1986–1987 and previously inaccessible to readers is presented. It is concluded on the basis of the experimental data on the actual contamination that there was no need for large-scale decontamination of the banks of the water reservoirs of the Dnieper cascade.     

Radioactive contamination of the environment with241Am as a result of the chernobyl accident

All Union Scientific-Research Institute of Nuclear Power Plants. Industrial Association "Chernobyk'skaya Atomnaya élektrostantsiya," Ukraine. Translated from Atomnaya énergiya, Vol. 77, No. 2, pp. 140–145, August, 1994.     

Characteristic features of the legal relations concerning compensation for injuries caused by the chernobyl accident

This article is devoted to the legal relations between the State and citizens who were victims of the accident at the Chernobyl nuclear power plant. Their characteristic features consist in the fact that the government as the constitutional guarantor and owner of nuclear power plants is responsible for the harm done due to radiation. The method of compensating for radiation damage in the form of compensations and benefits for harm to property and health of the victims was not known to the acting legislature before April 26, 1986. Compensations and benefits are also given to categories of citizens who are healthy and capable of working but were subjected to irradiation for risk of possible radiation-induced injury appearing in the future. 5 references. Concern Rosénergoatom. Translated from Atomnaya énergiya, Vol. 87, No. 1, pp. 68–71, July, 1999.     

Contamination of soil in the bryanskaya and ryazanskaya regions with long-lived radionuclides as a result of the chernobyl accident

Scientific and Industrial Association “Taifun.” V. I. Vernadskii Institute of Geochemistry, Russian Academy of Sciences. Translated from Atomnaya énergiya, Vol. 79, No. 3, pp. 233–235, September, 1995.