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Trends in the use of a unified information system for quality assurance and management at different stages of production of complexly shaped parts of aircraft engines are considered.

We developed a physicomathematical model to predict volcanic explosion-induced gasdynamic phenomena and the dynamics of the distribution of particles of ash and dust that precipitate onto the earth’s surface and that remain in the atmotsphere. We investigated the factors and processes that exert an influence on the transport of dust particles in the atmosphere. On the basis of the physicomathematical model developed, numerical simulation of volcanic explosions of specified power and space scale is done, and results on the dynamics of gasdynamic flows of air and the distribution of dust particles for different instants of time are analyzed.

Physical and mathematical models for computation of the energy release of an electron beam in a homogeneous magnetized plasma are developed. Profiles of the energy release in a carbon plasma as functions of various parameters of the beam and the plasma state are obtained.

Equations of convection in a gas are analyzed and a computational algorithm that is efficient when the condition μgh/RT≪1 is satisfied for an arbitrary (fairly large) temperature drop is proposed. Calculations of convection occurring in steady nonuniform heating of walls are performed for axisymmetric argoncontaining volumes of different shape. Results of these calculations demonstrate the establishment of steady and periodic motions of the gas.

Numerical simulation of the flow of air originating as a result of volcanic eruption is carried out with the parameters corresponding to those figuring in the eruption of the Krakatau volcano in 1883 (with an energy of 100–1000 Mton of TNT equivalent). The results of the calculation are compared with the consequences of the disaster known from the literature.

A generalization of the Harten TVD-scheme in the form of a predictor-corrector-type scheme of second-order accuracy in time and space is proposed for the flows with spherical and cylindrical symmetry. The scheme does not require introducing components with artificial viscosity and describes discontinuities in the solution without the appearance of nonphysical oscillations for a Courant number less than 0.8.

The redistribution function for resonance radiation in the Lα spectral line of hydrogenic ions in a dense hot plasma is calculated. The calculation is based on a self-consistent solution of the equations for the populations of the excited ionic sublevels and for the polarizations of the transitions considered. Nonlinear interference effects due to mixing of atomic states in both static and dynamic ionic fields are thereby taken into account. Molecular dynamics methods are used to account for the evolution of the multiparticle ionic field resulting from thermal motion of the ions. We calculate the Lα line of the hydrogen-like argon ion in a plasma with electron temperature 1 keV and electron density Ne=1022÷1024 cm−3. The rescattering function is compared with the approximation provided by complete frequency redistribution. The results demonstrate the limited usefulness of the latter approximation for a plasma consisting of multiply-charged ions.

A large number of complex experimental cases are considered which in recent years have been studied with the aid of the admittedly simplified apparatus of the Holstein theory. The fundamental Holstein equation is derived, starting with a system of coupled Boltzmann equations for the photons and the density of excited states. The derivation process provides opportunities for obtaining some intermediate kinetic equations with broader ranges of applicability than the Holstein equation. Some remarks are made concerning the combined transport in space of photons and excited atoms.

We review a number of the important results of the theory of radiation transport of resonance radiation obtained mainly during the past decade. Situations are stressed in which the traditional hypothesis of complete frequency redistribution of quanta is not fulfilled in the process of reemission. A quite general approach to the problem of radiation transport is presented that assumes small frequency shifts in the scattering event. Results are presented pertaining to the rate of deexcitation in Doppler, Stark, and natural mechanisms of line broadening. The transport of polarized radiation is discussed, including the application to experiments on interference of atomic states (the Hanle effect, etc.). The problem is discussed of transport of high-intensity radiation, in particular as applied to the problem of radiation trapping in lines of hydrogen-like ions. The connection is discussed of the physical mechanisms of radiation transport in spectral lines and in a recombination continuum.