Issue N^{o} 1, 1999 
COMPUTED DATA PROCESSING STRUCTURE FOR 3D GAS DYNAMICS PROBLEMS WITH HEAT CONDUCTION ON DISTRJBUTEDMEMORY PARALLEL COMPUTERS
O.I. Butnev, A.N. Bykov, N.V. Shumilina, V.A. Pronin VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 38.
The approaches are considered to the visualization of the results of 3D gas dynamics computations with heat conduction on distributedmemory parallel computers. The complexity of this problem is on the one hand in the representation of the function of three variables and on the other hand in the processing implementation of the functions distributed on several compute nodes. To analyze the functions of one variable NORS system is used, assembling a problem database using compression algorithms. To analyze the functions of two and three variables the programs were developed for assembling a file in a specialized format. A method is presented of data output from a specific part of a 3D problem using information, only located on the surface of the indicated part, that results in a major saving of the main memory. Principles and algorithms stated in this paper are used in two 3D complexes.

HIGH PERFORMANCE, PARALLEL COMPUTERS USING COMMERCIAL, OFFTHESHELF (COTS) COMPUTERS AND NETWORKS Dale E. Nielsen, Jr. VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 914.
An analysis was made of high perfomance, parallel computers using commercial, offtheshelf computers and networks. The operational data and cost are reported and discussed. Special attention is paid to the advanced parallel computer assembling technologies.

A NUMERICAL SOLUTION TECHNIQUE FOR MULTIDIMENSIONAL EQUATION OF HEAT CONDUCTION ON NONSTRUCTURAL GRIDS OF MEDUZA CODES WITH A METHOD OF LOCAL BALANCED ITERATIONS ON MULTIPROCESSORS B.M. Zhogov VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 1520.
For solving an equation of heat conduction with difference methods some algorithms and techniques are developed both for regular and for irregular grids. An algorithm is developed by the author for solving ал equation of heat conduction with a method of local balanced iterations on irregular grids for multidimensional case. This method is adapted for MEDUZA technique.

PARALLEL COMPUTATION STRUCTURE FOR 2D MULTIDOMAIN PROBLEMS OF HEAT CONDUCTION WITH D CODES ON DISTRIBUTEDMEMORY MP3 MULTIPROCESSORS V.I. Delov, L.V. Dmitrieva, D.M. Linnik, R.Z. Samigullina VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 2125.
Parallelization algorithm is studied for 2D multidomain heat conduction computations on distributedmemory multiprocessors. The algorithm under consideration is implemented with D codes intended for numerical calculations of 2D and 3D gas dynamics, heat conduction and elasticityplasticity in Lagrangian variables on regular grids. The results of parallelization algorithm evaluation on 8processor MP3 system are presented.

A NUMERICAL SMOOTHED PARTICLES HYDRODYNAMICS METHOD IN 3D FORMULATION FOR PHYSICAL PROCESS SIMULATION CONSIDERING THE COLLISION AND IMPACT PROBLEMS V.V. Bashurov, A.V. Patyanina VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 2638.
A smoothed particles hydrodynamics method is based on 3D freeLagrangian algorithm not using a regular grid and regular grid functions. The continuum conservation laws written in the .form of differential relations are transformed into integral relations using interpolating function allowing to evaluate quantity field values in a point. As no space grid exists a space differentiation is carried from physical quantities to interpolating core, which represents an analytical function. The algorithm describes medium elements as material clouds smeared along the space which mass centres move according to conservation laws of continuum dynamics. Any physical quantity in any point of the space is evaluated by summing inserts from each particle into this point. A necessary stability condition was obtained for 3D gas dynamics formulation using a spectral analysis method. The results of a given numerical method application are presented for physical process simulation.

MULTITHREAD SIMULATION OF ELASTICPLASTIC FLOWS WITH SPHMETHOD IN WINDOWS NT OPERATIONAL ENVIRONMENT V.V. Bashurov VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 3941.
This work outlines a smoothed particles hydrodynamics method (SPHmethod), a multithread parallelization principle for this algorithm in Windows NT operational environment and computed data for test problems in single and multiprocessor variants.

A COMPUTING METHOD PARALLELIZATION FOR LASER FUSION PROBLEMS G.V. Dolgoleva VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 4244.
SND code parallelization pursued two aims. The first aim is to have computational multiprocessor version of the code and the second one is pure methodical: to ascertain if the codes constructed on the principle of splitting by physical processes can be effectively parallelized. A typical class of the tasks which solution requires taking account of a large number of various physical processes — are the controlled fusion (laser or heavy ionic) tasks. A great number of physical processes are traditionally taken into account in the codes sequentially. Numerical algorithms depend on execution priority of physical processes. Difficulty of parallelization of algorithms, constructed according to the principle of splitting by physical processes consists in strict priority of their execution. It was desirable when parallelizing to retain the difference schemes used in a program and tested by many years operating experience. Physical processes computed with SND code are enumerated. A scheme and a method parallelizing mechanism are described, the examples of multiprocessor numerical calculations are given.

AN OPTIMUM COMPOSITION SELECTION FOR NIF TARGET SHELL E.M. Antonenko, N.N. Degtyarenko, G.V. Dolgoleva, G.M. Eliseev, V.F. Ermolovich VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 4552.
The numerical study results for compression and combustion of a capsule, proposed for investigation in NIF laser project (USA) are presented. The relation of energy output from a capsule and the relation of ignition margin for deuteriumtritium gas to copper atom concentration αCu in beryllium shell and temperature on its surface are constructed using ALF code. The shell composition is determined to reach the maximum energy output from a target. For these studies the spectral and onegroup ranges for beryllium and copper mixture were obtained using PERST3 code within the scope of MIXER technology. To estimate the assurance of range values they are compared with data, resulting from measurements and computations using other programs.

A CONSERVATIVE DIFFERENCE SCHEME FOR SCHRODINGER NONLINEAR EQUATION Yu.F. Kir´yanov, M.L. Kudryavtseva, N.V. Maslov, I.V. Shestakova VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 5360.
The study is made of a finitedifference scheme with the second order approximation for Schrodinger nonlinear equation, which conserves two first motion integrals. The conservation of these integrals in a bounded domain for Schrodinger 2D nonlinear equation is demonstrated and the results comparative computations for two problems with a proposed scheme and a splitting scheme are presented. The computations were carried out of a collision of two solitons in 1D problem and of a zero Gauss mode reflection in the medium without saturation in 2D problem.

A NUMERICAL METHOD FOR 2D GAS DYNAMICS CALCULATIONS USING AN ADAPTIVE LAGRANGIAN GRID IN D PROGRAM SYSTEM O.O. Murugova, Yu.D. Chernyshev VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 6167.
An algorithm for an adaptive Lagrangian grid construction in D programm system is presented. A computational grid gets condensed before a shock and detonation wave and gets rarefied after it has passed. The grid constructed is adaptivemobile due to Lagrangian type of a method and adaptivebuiltin. Test computations are given to show that the use of adaptive grid results in substantial increase in computations accuracy. T is expected to be continued as applied to 2D flows.

THE APPLICATION OF THE ADAPTED INDIVIDUAL PARTICLE METHOD FOR 2D ELASTICPLASTIC COMPUTATIONS V.I. Delov, R.M. Shagaliev VANT. Ser.: Mat. Mod. Fiz. Proc. 1999. No 1. P. 6874.
Тhis work presented the main feature, of the INCHM method which is an adaptation of the individual particle method m meshes, intended for computing multicomponent media Sows with large scheme of the method proposed has the second order of space and toe approximation with particles symmetrically arranged about Eulerian grid сеlls and is conservative in mass and energy. Computed data for some gas dynamics problems are presented. The computed data are compared with exact solutions, experimetal data and the results of the similar computations using D and EGAK methods.

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