ON CALCULATION OF OXYGEN BALANCE OF MULTICOMPONENT THERMOBARIC EXPLOSIVE SUBSTANCE

Most modern military confrontations take place near or directly in inhabited area. The use in such conditions of munition (warheads) which hit typical targets based on fragmentation (high-explosive) or cumulative action is impractical due to insufficient “selectivity” of hitting targets with such munition. At present, modern world tendency is the development of the latest munition (warheads) with increased properties of “destruction selectivity”. One of the directions is the development of munition based on thermobaric explosives. Such munitions can cause maximum damage due to high temperature and the impact of a shock wave with a low level of collateral damage, since thermobaric munition, especially in the open area, have a clearly defined or even limited area of effective damage, which determines the significance of their further development. Since modern thermobaric explosives include a large number of chemical elements (including chemically active metals), there is a need to calculate the physical balance of oxygen and oxygen coefficient to take into account the physical characteristics of modern multicomponent thermobaric explosives. The oxygen balance of multicomponent thermobaric explosives largely determines the nature of the reaction of its explosive transformation, i.e the composition of the explosive products and, consequently, the value of thermodynamic characteristics such as heat, temperature, volume and pressure of gas-like explosive products. The calculated ratio and coefficients for complex multicomponent thermobaric explosives should be calculated during the development of explosives, taking into account the composition of components and elements and their possible chemical reactions during the explosion. The abovementioned improved calculations of oxygen balance and oxygen coefficient of thermobaric explosives, which include aluminum, allows taking into account the physical characteristics of destruction of typical targets by thermobaric munitions.

Considerations on the Use of Explosive Substances for the Destruction of Metallic Structures

Incidents with IEDs containing metallic elements in the vicinity of the explosive substance pose a high degree of risk, endangering safety, peace and public order. In such situations, the methods and procedures applied as response by the authorities are cumbersome and risky, given the improvised nature of these incidents. In this paper we intend to analyze the destructive effect of explosive substances on certain metallic materials and we focus on a U-shaped metallic structure.

Improving the Effectiveness of Protective Means through Modelling the Initial Kinematic Parameters of the Fragmentation Field

The purpose of this article is to develop a mathematical model describing the process of forming the initial kinematic parameters of the fragmentation field. Efforts to increase the effectiveness of ammunitions have been explored, namely increasing the area of damage, by using system for continuous initiation of the explosive substance. The results obtained can be used in the development of ammunitions designed for countering terrorist and other threats as components of critical infrastructure protection systems.

Calculation and Experimental Validation of Pressure and Temperature Effects on COG-Air Fuel Mixtures

COG have been widely used together with blast furnace gas and blast furnace oxygen gas in the steel industry in Moravian-Silesian region of Czech Republic. COG is a flammable and explosive substance. Most explosion characteristics published so far are valid for pure compounds and limited experimental conditions, mostly ambient. There have been no explosion characteristic exists for COG-air mixtures which cover industrial conditions up to 423 K. Experimental tests have been carried out in a 20-L closed explosion chamber adopted for the explosion tests. The element potential approach in the thermochemical equilibrium calculations applied in the Chemkin subroutine has been used for explosion pressure calculations. Different explosion characteristics have been reported in a range from 298 K up to 423 K and from 0.5 bar(a) up to 1.0 bar(a).

Modeling the Failure Tree Analysis for Safety-Critical Systems in the Production of Hazardous Materials

During a manufacturing process of automotive clutch an explosive substance – xenon is produced. Concentration of this substance must be monitored. Implementation of controls is performed by a safety-critical functions control system.Among main role during the process of risk assessment analysis belong determination of danger and dangerous events associated with the devices. Proactive planning errors and the use of appropriate standards can greatly reduce formation disorders thereby reducing the probability of dangerous consequences. The standard safety subsystems architectures and computation methods for determining the failure intensity is listed in the standards IEC 61508 and IEC 61511. These standards contain information tables with the results of these computations for selected parameter values.We propose a complete failure probability model for the safety functions of the control system. This model is designed to compute the intensity of the critical failure for the standard channel architectures.These architectures were designed with respect to the standard IEC 61508 and were implemented in Matlab.