PREPRINTS

Preprint IBRAE-97-12

Likhanskii V.V., Matveev L.V. 

The survey of experimental investigations of nuclear fuel behaviour during its quick heatup is carried out. The models are proposed which describe various modes of relaxation of grain boundary porosity at sharp temperature increase in the absence of irradiation. The criterium of the beginning of the "brittle" mode of the grain boundary bubbles relaxation and the expression for their final radii are presented. The rate of diffusion growth of the grain boundary bubbles is calculated, and the conditions are pointed out for which the diffusion relaxation of the bubbles takes place. In addition various stress sourses in inhomogeneously heated fuel pellet are considered. 

Bibliographical reference

Likhanskii V.V., Matveev L.V. THE BEHAVIOUR OF SPENT FUEL UNDER TRANSIENT ACCIDENT CONDITIONS. Preprint IBRAE-97-12. Moscow. Nuclear Safety Institute. July 1997. 22 p. — Refs.: 29 items.

Preprint IBRAE-97-11

Petritis D.V. 

Presented in this paper is a mathematical model of vibrating dynamics of the ruptured above-ground pipeline. This model is based on the joist approximation. It allows to correlate technical and physical parameters of the pipeline and pipe flux with the distance between the immovable supporters that guarantees stability. 

Bibliographical reference

Petritis D.V. THE APPROXIMATE ANALYSIS OF THE ABOVE-GROUND PIPELINE STABILITY. Preprint IBRAE-97-11. Moscow. Nuclear Safety Institute. June 1997. 18 p. — Refs.: 25 items.

Preprint IBRAE-97-10

Panchenko S.V., Savkin M.N., Shutov V.N. 

The development of the methods for radiological hygiene reconstruction on lands contaminated by the Chernobyl accident are examined from the historical point of view. Attention focuses on the dose estimation for the population as well as on structure of the dose distribution. Summary data on the major dose contribution factors are given. 

Bibliographical reference

Panchenko S.V., Savkin M.N., Shutov V.N. THE RADIATION-HYGIENIC SITUATION AND DOSES TO THE POPULATION. Preprint IBRAE-97-10. Moscow. Nuclear Safety Institute. June 1997. 19 p. — Refs.: 39 items.

Preprint IBRAE-97-09

Kanevsky M.F., Kiselev V.P., Krylov A.L., Krylov S.F., Martynenko E.D. 

Description of computer model for calculation of annual dose from ingestion of radionuclide contaminated food is presented. Model is realized for MS Windows operational system and can operate in two modes: interactive and package. MS ACCESS format is used for database. Main functions of computer model are presented. 

Bibliographical reference

Kanevsky M.F., Kiselev V.P., Krylov A.L., Krylov S.F., Martynenko E.D. COMPUTER MODEL FOR CALCULATION OF ANNUAL INTERNAL DOSE “RATION-DOSE”’ (version for MS WINDOWS). Preprint IBRAE-97-09. Moscow. Nuclear Safety Institute. May 1997. 20 p. — Refs.: 2 items.

Preprint IBRAE-97-08

Aksenova A.E., Chudanov V.V., Churbanov A.G., Vabishchevich P.N. 

The some approaches for the numerical solving of diffusion/convection problem with solid/liquid phase change are considered. Special attention is given to the numerical methods for solving many dimensional Stefan problem with using of fixed grid techniques. Results on the use temperature formulation and fixed grid techniques in a solving of the standard benchmark problem are reported. 

Bibliographical reference

Aksenova A.E., Chudanov V.V., Churbanov A.G., Vabishchevich P.N. NUMERICAL APPROACHES FOR THE SIMULATION OF DIFFUSION/CONVECTION PROBLEM WITH SOLID/LIQUID PHASE CHANGE (in Russian). – Preprint № IBRAE-97-08. Moscow: Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 1997. – 25 p. – Refs.: 49 items

Preprint IBRAE-97-07

Varenkov V.V., Pervichko V.A., Popkov A.G., Chudanov V.V. 

This paper describes subsystem for working with data in computational code RASPLAV. Input and output data are stored in. files with special format. Text file of parameters defines input and output data flows for calculation module. The paper describes format of file of parameters and library for work with data on FORTRAN language. Example demonstrates the main ways of work with the subsystem. 

Bibliographical reference

Varenkov V.V., Pervichko V.A., Popkov A.G., Chudanov V.V.  DBV — SUBSYSTEM FOR WORKING WITH DATA BASE FOR VARIABLES (in Russian). Preprint IBRAE-97-07. Moscow. Nuclear Safety Institute, April 1997. 30 p. – Refs.: 5 items.

Preprint NSI-1996-03

Belikov V.V., Belikova G.V., Fokin A.L., Semenov V.N., Sorokovikova O.S., Starodubtseva L.P. 

This article presents the results of comparison of two atmospheric radionuclides transport normative methods (Russia and USA) with lagrangian stochastic one, developed in IBRAE RAS for integrated system “Nostradamus”. It is shown that for standard conditions where there are many experimental observations, the results of all methods are near. For nonstandard conditions (small or big wind speed) the results of the normative methods are distinguish from experience, but lagrangian model describes such phenomena adequately. 

Bibliographical reference

Belikov V.V., Belikova G.V., Fokin A.L., Semenov V.N., Sorokovikova O.S., Starodubtseva L.P. COMPARATIVE ANALYSIS OF NORMATIVE MODELS FOR THE TRANSFER OF RADIONUCLIDES IN THE ATMOSPHERE WITH LAGRANGE’S MODEL, USED IN THE INTEGRATED PACKAGE “NOSTRADAMUS”. Preprint NSI-1996-03. Moscow. Nuclear Safety Institute. 1996. 12 p. – Refs.: 15 items.

Preprint IBRAE-95-13

Aksenova A.E., Chudanov V.V., Vabishchevich P.N. 

The quasisteady natural convection of a heat-generating fluid with regard to solidification for the different cooling regimes on the boundaries is investigated numerically in present work. The main goal of this paper is correlation relations for the Nusselt numbers, volume of solid phase, temperature etc. depending on Rayleigh and Ostrogradskii numbers.

To solve unsteady problems of hydrodynamics with heat conductivity, new efficient numerical method, inspected at the wide set of test problem, was employed. The obtained numerical results were verified on reabilit.y via conducting of calculations on the sequence of the fine grids.

These results may be used for construction of simplified models describing the behaviour of a molten heat-generating masses (corium) in different retention system(core catcher).

Bibliographical reference

Aksenova A.E., Chudanov V.V., Vabishchevich P.N. NATURAL CONVECTIVE HEAT EX­CHANGE OF A HEAT-GENERATING FLUID FOR DIFFERENT COOLING REGIMES ON THE BOUNDARIES (in Russian). – Preprint № IBRAE-95-13. Moscow: Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 1995. – 22 p. – Refs.: 16 items

Preprint IBRAE-95-11

Aksenova A.E., Chudanov V.V., Churbanov A.G., Vabishchevich P.N. 

A review of heat and mass transfer models in the mushy region formed during binary system solidification is presented. Enthalpy formulation of problem on fixed grids is considered. A review of basic numerical techniques for solving of these problems with a moving boundary (phase change interface), namely, methods with moving boundary-smearing are considered. 

Bibliographical reference

Aksenova A.E., Chudanov V.V., Churbanov A.G., Vabishchevich P.N. NUMERICAL SIMULA­TION OF SOLIDIFICATION PROCESSES IN DIFFUSION/CONVECTION PROBLEMS. Re­view. – Preprint № IBRAE-95-11. Moscow: Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 1995. – 30 p. – Refs.: 113 items

Preprint IBRAE-95-09

Aksenova A.E., Chudanov V.V., Vabishchevich P.N. 

The quasisteady natural convection of a heat-generating fluid with regard to solidification for the different cooling regimes on the boundaries is investigated numerically in present work. The main goal of this paper is investigation of different cooling regimes influence on the distribution of heat flux on the cavity boundaries.

To solve unsteady problems of hydrodynamics with heat conductivity, new efficient numerical method, inspected at the wide set of test problem, was employed. The obtained numerical results were verified on reability via conducting of calculations on the sequence of the fine grids.

These results may be used for construction of simplified models describing the behaviour of a molten heat-generating masses (corium) in different retention system (core catcher). 

Bibliographical reference

Aksenova A.E., Chudanov V.V., Vabishchevich P.N. NUMERICAL INVESTIGATION OF A HEAT-GENERATING FLUID WITH REGARD SOLIDIFICATION FOR DIFFERENT COOLING REGIMES ON THE BOUNDARIES. Part II. (in Russian). – Preprint № IBRAE-95-09. Moscow: Nuclear Safety Institute of the Russian Academy of Sciences (IBRAE RAN), 1995. – 16 p. – Refs.: 17 items