SCIENCE & EDUCATION

The authors present a review of works dealing with the problem of shock explosive initiation; this review covered shock pulses administered by a single high-speed penetrator or by a flow of several penetrators. Expressions describing particular cases of interaction between an explosive charge and two high-speed penetrators are included in the article. Feasibility of numerical simulation was asserted to be the principal research technique for studying such high-speed processes. Different numerical setups using the AUTODYN 2D and 3D hydrocode are considered. Reasons behind planar symmetry used in a two-dimensional setup are included in the article. The authors show good agreement between the results obtained using two-dimensional setup with planar symmetry and results obtained during three-dimensional numerical runs.

The authors show the possibility of simple analytical evaluation of properties of multicomponent explosive mixtures with known properties and weight percentage of components. Expressions that expand the applicability of additivity laws were obtained from known shock wave theory relations for specific volume, density, isentrope exponent, explosive heat, detonation speed of explosive mixture. The authors provide a technique of calculation of detonation properties of explosive mixtures for a general multicomponent explosive, for two-phase medium and for a mixture of explosive and inert additive. An analytical shock adiobatic curve of a multicomponent explosive could be easily derived from the obtained results. This may be particularly useful for estimation of detonation process behavior in explosive mixtures when there is no experimental data concerning their particular properties.

This paper covers the research results oand analysis of methods and means of technical assessment of the condition of Earth remote sensing (ERS) systems during the test and on-stream periods. The obtained results are to provide a basis for further development of testing equipment for Earth remote sensing systems; moreover, they will provide a huge base of technical documentation (standards, guidelines for aircraft equipment testing etc.) for estimation of basic parameters which characterize the efficiency of application of digital observation equipment and their technical condition. The authors proposed a technique of online testing of the transfer function of remote sensing equipment during the on-stream period with a subsequent compensation of defocusing.

The article deals with the problem of designing microwave diagnostic systems, which are used in multifactor stressful conditions and require multi-parameter optimization with involving various disciplines, such as thermodynamics, mechanics and electrodynamics. Complex assessment of mechanical and dielectric properties of materials for use as a load-bearing element and a matching element of the microwave path was carried out. Simulation of the unit was performed using the software HFSS – a CAD package for the electrodynamics modeling; the simulation resulted in the definition the optimal geometry of the waveguide for the particular conditions.

The results of thermodynamic, ballistic, physic-mathematical surveys of low-temperature, gas-generating, fast-burning fuels (LGFF) characteristics. These fuels are pyrotechnic type based on nitroguanidine, ammonium perchlorate and methenamine, proposed for systems to move elements of actuators (SMEA), in particular, for gas generators (GG), for systems to open-close the underwater missiles’ steering devices (SOCSD). There are strict requirements for reaction time of these devices; it leads to the necessity of LGFF with high burning rate usage. Twenty chemical combinations were considered as modifiers to increase the burning rate. Based on obtained characteristics for different kinds of modifiers, high efficiency LGFF was created. The fuel was tested in GG and SOCSD. The results of those tests completely meet the requirements.

The article deals with the effects of non-ideal initiation and propagation of detonation in the equipment of weapons and ammunition, the basics of principles of operation of which is directed detonation-wave transmission of the explosion energy of charges of condensed explosives. The main causes of these effects and their influence on the functioning of explosive devices are analyzed. The data on the degree of influence of this factor on the stability characteristics of the damaging effect of modern high-performance ammunition was offered for cumulative and shell forming types, designed to destroy armored vehicles at long range.

Technology imperfections, operational and functional affects on high explosive charges of projectiles and ammunitions cause birth structural defects. Influence mechanisms of compact and flat local defects on the evolution of detonation wave were studied with the help of computational fluid dynamics method. Amplitude of detonation wave front deformations in relation to the compressible behavior of point defects and cracks with different orientations was calculated.

This paper deals with the basic principles of physical  simulation  of units starting complexes. Simulation was performed  by using the methods of finite elements and superelements. As an example, the authors present a physical model of the starting system for space rockets family "SOYUZ". The results were used for the design of the starting system in French Guiana.

The authors consider parametric studies of different factors’ influence on the working process characteristics in the combustion chamber(CС) of rocket thruster (RT), which made it possible to formulate recommendations regarding operating regime optimization and CC sizes. The authors obtained calculation dependences of the coefficient of the consumable complex and parameters of the RDMT combustion chamber working process on influencing factors with the use of gaseous oxygen as oxidizer, and kerosene – as a combustible. The authors provide a comparative analysis of the results of using these two components under similar conditions, which made it possible to determine the influence of physical properties of the combustible component on the effectiveness of working process organization.

Mathematical model of stalky elements’ oscillation in expanding big truss construction considering non-linear stiffness properties of hinge joints in the gravity field was considered. Frequency of the oscillation with strokes dependence on oscillation amplitude for different values of mass and stiffness properties of stalky elements was obtained. Developed mathematical model could be used when designing and researching of own dynamic characteristics of similar constructions.

This paper covers the study of developing a method and means of creating requirements for navigation equipment, aircraft control systems and aerial reconnaissance systems to ensure the required quality of aerial films. In their research the authors attempted to apply system analysis to airborne prospecting complexes created on the basis of using aerial cameras, particularly digital ones. The goals of this analysis are: support of flight task development for aerial reconnaissance aircrafts in service; support of prospective complexes development subject to real-time use.