Stationary shock wave in a two-temperature gas-solid particle mixture with account of melting

An analysis is made for various types of shock waves in a mixtures of gas and solid particles with account of their melting and the real kinetic equation of melting. The mixture flow is equilibrium in velocity and nonequilibrium in temperature of the gas and condensed phases. The existence of the predicted types of mixture flows, in particular, a flow with a soliton-like distribution of gas temperature, is confirmed by numerical calculations.Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, 630090 Novosibirsk. Translated from Fizika Goreniya i Vzryva, Vol. 30, No. 3, pp. 100–107, May–June, 1994.     

On propagation of a shock wave in a porous material upon collision of plates

The results of studying the propagation of shock waves in porous aluminum are given. Agreement between experiment and numerical calculations based on a model that takes into account the influence of a plastic zone is demonstrated.Institute of Theoretical and Applied Mechanics, Novosibirsk 630090. Translated from Fizika Goreniya i Vzryva, Vol. 31, No. 4, pp. 79–83, July–August, 1995.     

Role of particle collisions in shock wave interaction with a dense spherical layer of a gas suspension

The problem of interaction of an expanding spherical shock wave with a layer of particles is considered within the framework of the model of mechanics of continuous media with due allowance for granular pressure in the dense gas suspension. The influence of particle collisions on the shock wave expansion process is analyzed. Generation of collisional pressure and formation of shock wave structures in the gas suspension are found to be the governing factors of motion of the cloud of particles at the initial stage.     

Effect of collision dynamics of particles on the processes of shock wave dispersion

Based on numerical simulations of two-dimensional unsteady flows of gas suspensions, the contribution of particle collisions to dispersion processes during interaction of shock waves with dense dust layers is analyzed. A model of collision dynamics of the two-phase medium based on molecular-kinetic approaches is used. The model is tested by using a problem of a shock wave passing along a dense layer of particles; the model predictions are found to agree well with available experimental data. The problem of interaction of a blast wave with a dense layer on a flat surface is also considered. A comparative analysis of various mechanisms acting on particles and the influence of the initial parameters of the layer on the particle lifting dynamics is performed. A weak effect of the Saffman force and inhomogeneity of the layer surface (waviness) and a significant effect of the Magnus force on dispersion of the layer directly behind the shock wave are demonstrated. In some cases, the contribution of the particle collision dynamics is found to be comparable with the Magnus force effect. Dust lifting due to the development of the Kelvin–Helmholtz instability occurs at late stages of the process.     

Recording the particle velocity spectrum at the time the shock wave reaches the surface of liquids of different viscosities

This paper presents the results of experimental studies of the cavitation breakdown of liquids in a wide range of shock-wave loading. The free surface velocity of liquids and the velocity spectrum of the cloud of particles and jets were measured using a laser heterodyne interferometer (photon Doppler velocimetry), and their size was determined. The spall strength of distilled water was determined.     

Interaction of a shock wave with a cloud of particles

The present paper is devoted to experimental and theoretical investigation of shock-wave propagation in a mixture of a gas and solid particles with clearly defined boundaries of the two-phase region (cloud of particles). The effect of qualitative transformation of supersonic flow behind a shock wave in a cloud of particles is shown experimentally and substantiated theoretically for volume concentrations of the dispersed phase of 0.1–3%.Translated from Fizika Goreniya i Vzryva, Vol. 32, No. 2, pp. 86–99, March–April, 1996.     

Attenuation of a shock wave in organoplastic

The attenuation of a plane shock wave in organoplastic was experimentally and numerically investigated during its interaction with an overtaking rarefaction wave. Measurements were carried out with manganin gauges, An earlier formulation model of the dynamic deformation of composites was used in calculations. A comparison of calcualted and experimental data has shown their good agreement.Lavrent'ev Institute of Hydrodynamics, Russian Academy of Sciences, Novosibirsk 630090. Translated from Fizika Goreniya i Vzryva, Vol 31, No. 2, pp. 125–130, March–April, 1995.     

Electric perturbations in the atmospheric surface layer caused by an aerial shock wave

The low-frequency electric field associated with the propagation of an aerial shock wave in the atmospheric surface layer was studied experimentally and theoretically. The experiment involved the recording of variations of the vertical component E₂ of the electric field strength in the atmosphere by means of electrostatic flux meters and rod antennas set up on the surface of the ground. Analysis of the experimental data shows that electric field perturbations are caused by changes in the shock wave density of the volume electric charge formed by heavy ions and aerosol particles. An approximate proportionality is observed between the amplitude of electric field perturbations, shock wave parameters, and concentration of charged particles in the atmospheric electrode layer.Institute for Geosphere Dynamics, Russian Academy of Sciences, 117334, Moscow. Translated from Fizika Goreniya Vzryva, Vol. 30, No. 1, pp. 117–121, January–February, 1994.     

Reflection of a shock wave in a dusty cloud

The problem of shock-wave passage along a cloud of particles adjacent to a solid surface is studied numerically and analytically. The wave pattern of the flow near the shock wave reflected from this surface is analyzed within the framework of the equilibrium approximation of mechanics of heterogeneous media. The conditions of the transition from regular to irregular reflection from the substrate of the refracted shock wave inside the cloud are obtained analytically. The results of numerical simulations of a nonequilibrium flow in the two-velocity two-temperature approximation are compared with data obtained in the equilibrium approximation. Nonequilibrium and equilibrium flows are found to become more similar as the particle size decreases. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 1, pp. 121–131, January–February, 2007.