R. V. Arutyunyan

Chernobyl Fallout: Review of Advanced Spatial Data Analysis

The paper is based on the long experience in applying various spatial data analysis methods and approaches to the radioactive pollution data after the Chernobyl accident. Application of three basic approaches are described in the work: geostatistics (both parametric and non-parametric models), artificial neural networks (ANN) and monitoring network analysis, including fractals and cluster analysis. There have been developed hybrid geostatistical-ANN models, which show better performance then one approach models in many complex non-stationary cases.

Assessment of Parameters of Radioactive Aerosol Release Through Air Duct System Using the SOCRAT/V3 Code

Abstract Specialized computer codes that model the behavior of aerosol particles propagating through a system of pipes or air ducts are used for assessment of aerosol particle deposition. Developed in Russia, SOCRAT/V3 is one such code. SOCRAT/V3 was used for modeling of the transport of radioactive aerosols containing the 137Cs radionuclide through an air duct during a real emergency. The obtained results of the modeling were used to estimate the exposure dose rate (EDR) of gamma radiation near the air duct. The results of the estimation were compared with data of real measurements of the gamma-radiation EDR along the air duct. This paper proposes an approach to assessment of source term in the case of radioactive aerosol releases using (1) a thermophysical code (SOCRAT/V3), allowing modeling of physical processes that influence the formation and transport of aerosols, and (2) data of in situ measurements for the external EDR from contaminated air ducts.

Comparison of the results of 85 Kr transport modeling with the ACURATE field experiment data

Currently the Nuclear Safety Institute of the Russian Academy of Sciences (NSI RAS) jointly with the Hydrometcenter of Russia is developing the system for forecasting the transfer of radio-active substances in the atmosphere in case of radiation accidents at Russian nuclear power plants. The operation of the system is based on the numerical hydrodynamic model which allows forecasting meteorological parameters and is coupled with the mesoscale dispersion model of the transfer ofradioactive substances in the atmosphere. The results are presented of 85Kr transport modeling under the conditions of the ACURATE experiment with three transport models: FLEXPART, HYSPLIT, and the model from the NOSTRADAMUS software package. It is demonstrated that all three Lagrangian models can give a qualitative description of concentration fields from the ACURATE experiment with the best value of the RANK metric (2.5) based on three statistics.

Description of radiation conditions and evaluation of the date of 137Cs release to the atmosphere using the radionuclide transfer model coupled with the forecasts by the mesoscale hydrodynamic model

The estimates of 137Cs emissions from the accident happened in Elektrostal at the beginning of April 12, 2013 are presented. The transport of radionuclides and their dry and wet deposition on the surface are computed using the Lagrangian stochastic model of the NOSTRADAMUS software package worked out by Nuclear Safety Institute of Russian Academy of Sciences. Prognostic fields of wind (horizontal and vertical components) in the lower troposphere, precipitation, and vertical and horizontal turbulence diffusivity coefficients in the lower atmosphere (up to 4 km) were used as input data. Prognostic fields were obtained using the WRF-ARW numerical mesoscale model.

On the possibility of the realization of combustion and detonation waves in a system of nuclear isomers

The possible regimes of the propagation of a self-sustained fluorescence wave of long-lived nuclear isomers, which is initiated by transitions to the nearest short-lived level owing to the absorption of X-ray photons and inelastic collisions of electrons in a plasma, have been analyzed. It has been found that, when the energy exchange between the nuclear subsystem and plasma is due to absorption and emission of photons, the fluorescence wave can propagate in the fast (with a near-light velocity) deflagration regime induced by the radiative heat transfer mechanism. When the energy exchange between the subsystems is nonradiative, the (slower) detonation regime becomes significant. The implementation of each of the two regimes requires certain conditions on the characteristics of the system.

Activities on Improvement of Radiation Monitoring and Emergency Response Systems in Russian Regions

Preparedness of the emergency response system to prevent and mitigate-consequences of radiation incidents and accidents is one of the most important elements of safe operation of nuclear power facilities. Everyday activities on prevention of emergency situations along with adequate and efficient response are the key factors, which reduce the risks of harmful impact on the population and environment. Both the high engineering level and variety of the nuclear branch facilities impose special requirements to the emergency response system. A powerful scientific and technical support system is required to solve various problems of emergency response.

Mobile Hardware and Software Complex to Support Work of Radiation Safety Experts in Field Conditions

The developed software and technical complex represents a mobile working place designed to support the work of radiation safety experts in case of emergencies, when leaving for the place of accident. It comprises required databases on normative documents in the radiation safety area; enquiry databases on objects, the personnel and equipment of emergency-rescue teams (ERT) from FAAE of Russia; the bank of electronic maps; computer systems for operative forecast and radiation environment measurement; the system to define geographical coordinates as well as a wide set of communication links to accept and transfer the data.

Experience in Applying Information Technologies to Ensure Safe Operation of Russian Nuclear Industry Facilities

In Russia, a Unified System of Emergency Response (RSER) one of the parts of which is Russia’s FAAE Branch System of Emergency Response has been created.

Software to Support a Specialized Bank of Electronic Maps

For a number of years, IBRAE RAS has run the activities to form the bank of topographic and subject-matter electronic maps/plans of various scales.

Chernobyl experience of emergency data management

The use of the Chernobyl experience in emergency data management is presented. Information technologies for the generalization of practical experience in the protection of the population after the Chernobyl accident are described. The two main components of this work are the development of the administrative information system (AIS) and the creation of the central data bank. The current state of the AIS, the data bank and the bank of models is described. Data accumulated and models are used to estimate the consequences of radiation accidents and to provide different types of prognosis. Experience of accumulated analysis data allows special software to be developed for large-scale simulation of radiation consequences of major radiation accidents and to organize practical exercises. Some examples of such activity are presented.