## Computer simulation of flow reactors

The numerical 3D modeling of the gas-dynamic reactants flows of a flow reactor and their mixing that was made with the FLUENT software package is discussed. The presence of the modes where a reaction zone with a high content of C2 hydrocarbons is localized in the center of reactor presented....

## Computer simulation of direct chemical kinetics tasks

A new technology for the simulation of physico-chemical processes in a reactive medium is proposed, which allows optimizing and adjusting kinetic schemes of chemical reactions. To implement the technology, a ChemPAK software tool, which is used to solve the primal problems of chemical kinetics, was developed. The proposed technological solution...

## Trust-Region solvers: performance and applications in geosciences

The Trust-Region (TR) algorithms are relatively new iterative algorithms for solving nonlinear optimization problems. High efficiency of the TR methods was demonstrated in a number of recent publications. They have the global convergence and local super-convergence, which differ them from the line search methods, commonly used for solving Inverse Problems....

## Computer simulation of radiation acceleration mode in laser-plasma interaction

We present numerical studies on the ion acceleration from thin foils irradiated by ultra-high contrast laser pulses. Two-dimensional particle-in-cell (PIC) simulations reveal that ions are for a certain time accelerated in a phase-stable way by the laser radiation pressure. The development of the Rayleigh–Taylor instability leads to destroy foils and...

## Application of schemes based on the differential approximation method to invariant solutions in the gas sphere expansion into vacuum

This paper considers the problem of obtaining invariant solutions under rotation transformation in the expansion of a gas sphere into vacuum in the Cartesian coordinates for the two-dimensional case. Numerical results are presented and a comparative analysis of conventional and invariant difference schemes is made. Various non-invariant difference schemes of...

## Monte Carlo simulation of multiple-scattered lidar returns (software description)

The paper deals with Monte Carlo simulation of the lidar return signals. Descriptions of mathematical model, simulation algorithms, and mathematical software are presented as well as results of several numerical experiments for ground-based and space-borne lidars.

## The study of the role of collisions within the beam-plasma interaction with a finite difference Vlasov solver

A 3D kinetic study of relaxation processes caused by the electron beam propagation in high-temperature plasma was carried out. This problem has two different spatial scales: the plasma Debye length and the beam-plasma interaction wavelength, that is, some 10 or 100 times larger, thus one needs high-performance computing to observe...

## Computation of gravitational potential of isolated systems in cylindrical coordinates

We present the new method for computation of a gravitational potential for isolated systems in cylindrical coordinates. This method solves the main difficulty arising when treating isolated systems: in order to correctly state the Dirichlet problem for the Poisson equation at the boundary of a finite computational domain, one must...

## Threshold functions for inserting or deleting particles in the PIC method with adaptive mass

The Particle-in-Cell methods (PIC) are widely used in the numerical simulation. The media under study in these methods are represented with a sufficiently large number of model particles with definite characteristics such as mass, charge, velocity. The evolution of a system of particles at each time step is evaluated in...

## A method for solving the mass problem of belonging a set of points to arbitrary coverings on GPU

This paper describes a numerical algorithm and results of numerical calculations of the mass problem solution of determination of belonging of a set of points to a set of arbitrary figures covering an area. Such figures could be irrelative crossed or not. The problem is solved by the earlier described...