Development of a process model for determining the composition and energy characteristics of a pyrotechnic mixture using the library method

Abstract

The range of changes in the characteristics of powder mixtures, even of the same brand, expands due to different storage periods and progressive degradation of the powders. The need to simplify the procedure for determining the composition and energy characteristics of the powders used is emphasized. The purpose of simplification is to increase the number of quality control points for incoming charges, bring them closer to combat formations, and reduce the requirements for service personnel. It is proposed to determine the actual composition and energy characteristics of the powder charge based on the library method. This approach requires a large amount of calculations – multiple solutions to the problem of equilibrium conversion of the original powder mixture into combustion products. But these calculations for a given brand of powder are carried out in advance, once and in laboratory conditions. The characteristics of a specific charge sample are determined using library data based on the measured technological parameters of its combustion process - the mass of the burned sample and the temperature of the powder gases. To be able to take into account soot formation and gaseous products of thermal destruction of powder when solving problems for filling the library, the equilibrium model of such a process has been modernized. Instead of partial pressures and concentrations of substances, their mole fractions are considered. The use of partial pressures is convenient when there are only gaseous products. The use of mole fractions made it possible to uniformly take into account the gaseous and condensed phases of combustion products. The modernized calculation model was verified by comparing the obtained results with known data. The need to validate the list of combustion products in each case under consideration was determined