Optimization of Construction of the rocket-assisted projectile

New scheme of the rocket motor of rocket-assisted projectile providing the increase in distance of flight due to controlled and optimal delay time of ignition of the solid-propellant charge of the SRM and increase in reliability of initiation of the SRM by means of the autonomous system of ignition excluding the influence of high pressure gases of the propellant charge in the gun barrel has been considered. Results of the analysis of effectiveness of using of the ignition delay device on motion characteristics of the rocket-assisted projectile has been presented

Gravitational sedimentation of cloud of solid spherical particles at small Reynolds numbers

The experimental results of study of gravitational sedimentation of highly-concentrated systems of solid spherical particles at small Reynolds numbers Re<1 are presented. Empirical equation for drag coefficient of the particle assembly has been obtained. The influence of initial particle concentration in the cloud on its dynamics and velocity has been analysed

Assessment of the effect of borides on the thermodynamic characteristics of heterogeneous systems

The possibility of creating high-energy materials with increased ecological purity of combustion products based on a mixed oxidizer (ammonium nitrate, ammonium perchlorate), and inorganic fuel (boron, diboride or aluminum polyboride) is shown

Dynamics of bubble rising at small Reynolds numbers

Results of experimental study of a single spherical bubble rising in the non-stationary regime in a viscous liquid (with and without surfactant) at small Reynolds numbers Re<1 have been presented. Improved empirical correlations for drag coefficient of the bubble rising with and without surfactant in the stationary regime have been obtained. Influence of nonstationary effects on the dynamics of bubble rising has been analyzed

Influence of dispersed heat-resistant additives on ignition and combustion of heterogeneous systems

The results of experimental studies of the effect of dispersion of heat-resistant additives powders on ignition and combustion of heterogeneous condensed systems. The method of measuring the time delay ignition conductive and radiant heating, and combustion rate at atmospheric pressure. The effect of additives powders of boron, silicon and titanium dioxide on the ignition and combustion of heterogeneous condensed systems

Identification of size and concentration of submicron particles on the basis of rayleigh scattering model

A method of identification of maximum size and concentration of submicron aerosol particles based on measurement of intensity attenuation of a parallel beam of probe optical radiation is described. Offered method makes it possible to determine both particle concentration and maximum particle size with controlled accuracy for aerosol media without any initial information about particle size distribution

Unsteady rise of a bubble in a viscous fluid at small Reynolds numbers

A bubble rising from the state of rest in a viscous incompressible fluid is considered. A formula for the Basset force acting on the bubble in a viscous fluid is obtained, which differs by a multiplier from the Basset force for a solid particle. The problem of unsteady rise of a bubble is solved analytically. The bubble rise is also studied experimentally and the experimental data are compared with the theoretical results

About determining the wettability of coal surface

A new method of measuring the wettability of coal powders based on determining the mass fraction of wetted powder particles at their interaction with water droplets during the process of gravitational sedimentation in a transparent cell has been proposed. Wettability parameter is calculated from the results of measuring the dependence of spectral transmittance of laser emission in the cell on time of powder sedimentation