Issue N^{o} 3, 2004 
DIRECT 3D NUMERICAL SIMULATION OF GRAVITATIONAL TURBULENT MIXING UNDER ALTERNATING ACCELERATION
V. A. Zhmaylo, O. G. Sin'kova, V. N. Sofronov, V. P. Statsenko, Yu. V. Yanilkin VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 315.
Evolution of turbulence on a plane interface of two incompressible fluids (gases) of different densities with density ratio n = 3 is investigated numerically using 3D hydrodynamic and gas dynamic codes. A case, when acceleration changes its sign at a certain time point, is considered. Results of computations are compared to the available data of experiments.

THE NEW COMPUTATIONAL METHOD FOR THERMODYNAMIC STATE OF MATERIALS IN MIXED CELLS E. A. Goncharov, Yu. V. Yanilkin VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 1630.
The paper offers the new algorithm of calculating the thermodynamic states of mixed cell materials in Lagrangian variables. An assumption of equal increments of pressure components for a time step underlies the algorithm. The distribution of general compression (extension) of a cell over its components is added by the iterationless mechanism of equalizing the component pressures, with the requirement of additivity of internal energies of components being used to determine additional contributions to the internal energies of components to support energy balance. Results of test computations are given, they demonstrate a rather high precision and efficiency of the algorithm.

THE INTEGRAL IMAGE RECONSTRUCTION ALGORITHM FOR TOMOGRAPHY E. N. Simonov VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 3143.
The image reconstruction algorithms for transmission Xray tomography are classified. Integral methods of image reconstruction in projections are discussed. The practical image reconstruction algorithms have been developed using the method of deprojection with convolution filtration for fan scanning geometry with a large number of counts in projection (more than 512) and image matrix 512 512 and more which have been implemented for the domestic Xray computeraided tomograph RKT01 designed for examination of the whole human body.

SIMULATION PROBLEMS IN XRAY COMPUTERAIDED TOMOGRAPHY E. N. Simonov VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 4453.
Numerical simulation was carried out to study the dependence of the quality of tomographic images on a) the number of perspectives and detectors (counts in projection); b) the level of noise in the measurement and projection data; c) instability of the Xray photon flux from a radiation source; d) fluctuation of perspectives and detector coordinates; and e) the Xray radiation spectrum. The numerical simulation resulted in determination of admissible variability of the abovementioned factors and also the design requirements to units and systems of the domestic Xray computeraided tomograph RKT01 having a fan radiation beam and a continuous line of single xenon detectors and intended for examination of the whole human body have been specified.

NUMERICAL SIMULATION OF FORMATION OF HIGHSPEED COMPACT METAL COMPONENTS S. S. Sokolov, A. A. Sadovoy, T. I. Chaika VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 5461.
The influence of damage mechanisms on the process of forming compact highspeed components has been studied. The earlier developed kinetic model of dynamic damages considering the damages both on unloads and during shear strains and describing the compacting processes sometimes taking place in the damaged materials has been used for the mathematical model. Numerical simulations were carried out by 2D DMK code for the hemispherecylinder type structure with an aluminum shell and the structure in the form of a slightly concave copper liner. It is shown that local damage zones in the head part are formed in the aluminum liner. For the copper liner, we didn't manage to achieve the agreement between the calculated damage zones and the data of experiments with the use of the chosen parameters of shear failures.

COMPRESSION OF A MULTIPLELAYER TARGET IN THE HEAVY ION THERMONUCLEAR FUSION SYSTEM M. D. Churazov, A. G. Aksenov, E. A. Zabrodina VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 6265.
The paper considers a possibility of using a cylindrical multiplelayer DTtarget for a thermonuclear energy system with a powerful accelerator of relativistic heavy ions. High energy and high power of ion beams (E_{0} ~ 100 MJ, P_{ow} ~ 9 000 TW) reliably provide both compression ( ~ 100 g/cm^{3}; R 0,4 g/cm^{2}) and ignition (T ~ 5 keV). The parameters of three ion beams irradiating the target have been chosen. The thermonuclear amplification factor of the target is G > 50, according to estimates.

BEHAVIOR OF A CYLINDRICAL SHELL WITH PARTIALLY DESTROYED HEATRESISTING COATING IN THE FIELD OF TEMPERATURES WITH SUBSEQUENT LOCAL COOLDOWN N. I. Obodan, N. B. Makarenko, N. A. Guk, E. M. Kiselev VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 6671.
The paper considers the behavior of a cylindrical shell with the damaged heatresisting coating in the field of temperatures that leads to heating the damaged area. After the heated area has been forcedly cooled down, residual stresses occur in it. The mathematical model is represented by equilibrium equations, elasticity correlations and boundary conditions on the shell edges. The method of additional deformations is used to determine plastic deformations. CherepanovRaise criterion was chosen for the destruction model. The fracture growth conditions are the result of varying the total energy of the distorted shell with regard to energy consumed for generation of the new surface of defect. The stressstrained state is determined using the method of finite elements by COSMOS complex of application codes. Computation results are given, the dependence of critical heating temperature on the size of the heated area of damages is determined.

MATHEMATICAL MODEL OF SHRINKAGE OF A SWELLING SOIL M. G. Khramchenkov, R. K. Khramchenkova, A. N. Chekalin VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 7275.
The paper offers a new theory describing the mechanical and physicalandchemical properties of clayey soils and grounds as natural swelling systems. The simplest problem of water squeezing out of a broad layer of finite thickness has been solved. Specific features of the solution found have been studied. Good agreement with the experimental data on the problem has been achieved. The relation has been found to determine the optimum size of waterstable soil aggregates.

IMPLEMENTATION OF MESSAGE PASSING INTERFACE (MPI) FOR THE DOMESTIC INTERPROCESSOR COMMUNICATION SYSTEM (IPCS) A. M. Vargin, D. V. Ezhov, Yu. L. Kir'yanov VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 7679.
The ideas of implementation of library of message exchange functions intended for operation of the interprocessor communication system developed and operated at RFNCVNIIEF are described. The library completely meets the international MPI1 standard requirements.

CENTRALIZED NETWORK PRINTING SYSTEM PrintMe I. M. Batyi, G. K. Kalinenkova, E. V. Morozova, A. B. Olesnitskii VANT. Ser.: Mat. Mod. Fiz. Proc. 2004. No 3. P. 8088.
The main ideas of operation of PrintMe system providing centralized printing within a local computer system are described. The system allows all network printing processes to be arranged according to the requirement of their allround control with regard to the kind of work and the system usability for users and the printing station maintenance personnel. Emphasis is put on the user information support, statistics issues, and the system operation reliability. Two versions of the system provide the two different levels of the system capabilities and the network printing service.

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