Published in Sarov (Arzamas-16), Nizhegorodskaya oblast
NUCLEAR CENTER -
ALL-RUSSIAN RESEARCH INSTITUTE
OF EXPERIMENTAL PHYSICS
Русский | English
Issue No 2, 1985
ON STABILITY OF THE SCHEME "KREST" FOR 2D MAXWELL EQUATIONS IN CYLINDRICAL COORDINATES
A. A. Solovyev
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 3-9.
Stability of the scheme "KREST" is examined for two -dimensional Maxwell equations in cylindrical (z, r) - coorinates using operator inequality method. Sufficient condition of uniform stability is obtained on the basis of initial data in HD - space, generated by a positive self-adjoint D - operator. For a uniform grid the stability criterium is brought up to relation allowing explicit estimation of maximum allowable time step. For inconducting medium this relation is shown to coincide with condition that is necessary for scheme stability in some norm and., therefore, is non - improving.
|TARGET COMPUTATIONS FOR LASER THERMONUCLEAR FUSION BY CODE "ZARYA" MODEL OF LASER RADIATION ABSORPTION BY A SPHERICAL TARGET
E. N. Avrorin, A. I. Zuev, Yu. N. Lasarev, V. A. Lykov, N. P. Sitnikov, O. S. Shirokovskaya
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 10-20.
Dependences of density profile steepening parameters under action of pondermotive forces, as well as resonance and parametric absorption coefficints at incidence of s- and p-polarized electromagnetic wave onto flat plasma layer are obtained on the basis of numerical solution of the set of contracted Maxwell equations combined with isothermal quasi-static plasma flow equat ions.
The model of absorption of laser radiation by spherical target is formulated, allowing to compute back-bremsstrahlung, resonance, and parametric absorption taking into account refraction of laser radiation in the corona, density profile steepening, and Mandelstam-Bri1louin forced scattering. One-group fast-electron energy transfer equation is proved.
|TARGET COMPUTATIONS FOR LASER THERMONUCLEAR FUSION BY CODE "ZARYA. COMPARISON WITH EXPERIMENTS AND OPTIMIZATION OF VARIOUS LASER-TARGET SYSTEMS
E. N. Avrorin, А. I. Zuev, N. G. Karlykhanov, V. B. Kryuchenkov, V. A. Lykov, V. E. Chernyakov
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 21-28.
Comparison between computational and test results with gas-filled glass shells is made on a number of devices at various laser pulse lengths, energy flow densities, wave lengths, and conit ions of laser radiation focusing. The computational results are shown to agree with tests as for amount of energy absorbed, gas compression, neutron yield, x-ray spectra, and obscurograms. Results of target optimization for lTw neodymium glass device, as well as of target calculations for obtaining thermonuclear burst and hybrid thermonuclear reactor on the basis of laser themro- nuclear fusion at various wave lengths of laser radiation are presented.
|REALIZATION PRINCIPLES OF MULTIPROCESSING IN OS SVS
Yu. G. Bartenev, V. M. Kukhtin, A. I. Lukin
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 29-35.
A technique is proposed for deriving an operating system for multiprocessig system of "Elbrus-1” (OS SVS) servers on the basis of operating system DISPAK designed for service of one-processing system. A prob1еm paralleling is discussed.
|A SOLUTION OF A NONLINEAR BOUNDARY-VALUE HEAT CONDUCTION PROBLEM IN INHOMOGENEOUS MEDIUM
G. Ya. Lyubarski, M. A. Khazhmuradov, V. A. Yamnitski
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 36-39.
A solution of a nonlinear boundary - value heat conduction problem is considered, which arises when laminated materials are irradiated by pulsed plasma flow. For the problem to be solved a variable - step implicit method of grids is applied for the first time. It is shown that the described method may be used for solving problems in which surface material temperature is as large as 2400K.
|ONE WAY OF ATTACHMENT OF SEMICONDUCTOR MAIN MEMORY TO BESM-6
V. E. Galperin, V. I. Igrunov, V. V. Kolesnikov
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 40-42.
Questions are considered arising when semiconductor main memory constructed on the basis of dynamic type memory chips K565RU3A are attached to BESM-6. A practical solution of these questions is given, a diagram of dependence of BESM-6 internal performance on memory cycle time is supplied at two memory access times.
|ON COMPUTING QUASI-REGULAR AND REGULAR MODE FOR TRANSFER EQUATION
V. Ya. Goldin, V. F. Yudintsev
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 43-49.
Some algorithms used to calculate quasi-regular and regular modes for nonstationary transfer equation are formulated and tested. Efficiency of the algorithms is examined on a number of numerical examples.
|SVET TECHNIQUE FOR SOLVING HEAT RADIATION TRASFER PROBLEMS
E. S. Andreyev, M. Yu. Kozmanov
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 50-57.
SVET technique is proposed for solving heat radiation transfer problems. The technique involves the characteristics method, supplemented with "balancing", considerably improving properties of the difference scheme and allowing computations to be run with energy balancing up to fractions of a per cent. The technique is extended to spectral case, the maximum-minimum principle allowing for scattering being proved for it. The technique proposed is efficient in solving problems of heat radiation propagation without regard to movement in media of low matter density and strong dependence of temperature and radiation intensity on time. It is of satisfactory accuracy, allows easy solution of problem of organizing iterations between energy and nonstationary radiation transfer equations.
|A ROUTINE FOR COMPUTING TWO-TEMPERATURE RADIANT GAS MOVEMENT WITH REGARD TO FAST CHARGED PARTICLES (ROUTINE ALOS)
G. V. Dolgolyeva, V. F. Ermolovich, I. N. Lukovkina, E. V. Feodoritova
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 58-61.
The mathematical model used as basis of the routine, the computational technique used, the main principles of routine organization are described. Results of some model computations are given.
|A METHOD OF SOLVING THREE-TEMPERATURE GAS DYNAMICS EQUATIONS
V. G. Nikolaev
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 62-67.
Iteration algorithms are suggested for solving difference schemes approximating ID heat conduction gas dynamics equations. The algorithms are based on the multidiagonal run meihod and are direct methods (without splitting) of solving difference gas dynamics equations. A method of defining heat flow is developed which is similar to flow run method. All the algorithms are applied to solving both one- and two-, and three-temperature gas dynamics equations.
|APPLICATION OF VARIATIONAL PRINCIPLES OF MECHANICS TO DEVELOPING TIME-DISCRETE DIFFERENCE GAS DYNAMICS MODELS. 1. DESCRIPTION OF THE METHOD ON SIMPLE EXAMPLES
Yu. A. Bondarenko
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 68-75.
A method of constructing simultaneously time - and space-discrete difference1 schemes is described for a set of gas dynamics equations in Lagragian variables. The method is based on the use the Hami1ton-Ostro-gradski principle, the time- and space-integrals of the Lagrangian function in action functional being replaced with appropriate quadrature formulas. The described method is a natural extension of variational method constructing differential-difference schemes for gas dynamics, developed in papers by Golovizin V. M., Samarski A. A, and Favorski A. P., and, in contrast with them, allows to construct time-difference approximations directly.
|APPLICATION OF ANTIDIFFUSION FLOW-CORRECTED TO TECHNIQUE COMPUTING 2D GAS DYNAMICS FLOWS IN LAGRANGE-EULER VARIABLES
S. M. Bakhrakh, V. F. Spiridonov, L. Ya. Trofimova, A. A. Shanin
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 76-86.
A method for computing 2D axisymmetric gas dynamics flows in Lagrange-Euler variables is presented. For the accuracy of the convective terms to be improved an antidiffusion flow-corrected technique (FCT) is used, applied in case of arbitrary 2D Lagrange-Euler mesh. Antidiffusion flow correction algorithms are considered, that provide the laws of conservation of mass, energy, and momentum and priciple of maximum for ρ, ρu, ρξ to be met. Conditions are formulated, at which the correction formulas, along with meeting conservation laws, provide the principle of maximum for density, specific energy, and velocity. Application of FCT method is discussed as for improvement of computationnal accuracy for inhomogeneous (consisting of several matters) medium gas dynamics flows. Computational results are given demonstrating the efficiency of the method suggested.
|ON A THREE-POINT DIFFERENCE SCHEME WITH WEIGHING MULTIPLIER FOR TRANSPORT EQUATIONS
E. V. Groshev, A. M. Pastushenko, V. F. Yudintsev
VANT. Ser. Metodiki i Programmy Chislennogo Resheniya Zadach Matematicheskoy Fiziki. 1985. No 2. P. 87-96.
An arrangement of a finite-difference scheme for transport equations is described which exhibits enhanced monotonicity of associated approximate solutions. Properties of the scheme were examined on a simple model equation and checked numerical calculations of a number of spherically-symmetric problems displayning satisfactory practical accuracy and monotonicity of the scheme suggested.
|[ Back ]