METHOD OF CONTROLLING PRESENCE OF FOREIGN SUBSTANCES AND OBJECTS IN THE BORE OF THE BARREL USING MONOCHROME LIGHT

In the article, the authors propose a method for controlling the presence of foreign substances and objects inside the barrel. The problem of surface cleanliness control remains relevant in many areas, ranging from sanitary cleaning to nanoelectronics. In the military sphere, this becomes particularly important during the cleaning of cannon barrels. Both powder combustion products and cartridge cap and bullet shell particles are deposited in the barrel during firing from guns. Under the impact of high temperatures, the bullet particles are partially oxidized and cover the barrel channel with a thin layer of deposit of oxides, which are difficult to dissolve. As a result, the density of the bullet abuting the walls changes. This affects the characteristics of its motion inside the barrel. The accuracy of the shot is reduced, and subsequently the precision and accuracy of shooting in general decreases. The essence of the proposed method consists in the fact that a light source is placed in the bore of the barrel on one side, and an optical device is placed on the other side, with the help of which the presence of foreign substances and objects is monitored. Unlike the known methods, this method is characterized in that several monochrome light sources in addition are placed in turn in the bore of the barrel from the breech part, and in the bore of the barrel from the muzzle part there is equipment for receiving (detecting) monochrome light. Then, obtained monochrome light is analyzed, current value of its defined parameters is determined. At the next stage, parameter values of monochrome light fixed during control are compared with parameter values of reference signatures, which had been obtained before the barrel was put in service. These values are stored in equipment memory. If the values of at least one of the parameters from at least one of the monochrome light sources are found to be inconsistent with the parameters of the reference signatures, the equipment for receiving and analyzing monochrome light gives a signal about the presence of foreign substances and objects in the bore of the barrel.

Preparation of Cu–Cu2O–CuO by solid combustion ignited by dielectric barrier discharge and its activity towards p-nitrophenol reduction

Dielectric barrier discharge induces solid powder combustion at room temperature and atmosphere to prepare a high-activity catalyst for p-nitrophenol reduction.

Renewable Pulverized Biomass Fuel for Internal Combustion Engines

Biomass is currently one of the world’s major renewable energy sources. Biomass in a powder form has been recently proposed as the most encouraging of biomass contours, especially because it burns like a gas. In the current study, biomass powder was examined, for the first time, as a direct solid fuel in internal combustion engines. The aim of the current study was to investigate modeling tools for simulation of biomass powder in combustion engines (CE). The biomass powder applied was in a micro-scale size with a typical irregular shape; the powder length was in the range of 75−5800 μm, and the diameter was in the range 30−1380 μm. Different mechanisms for biomass powder drying and devolatilization/gasification were proposed, including different schemes’ and mechanisms’ rate constants. A comparison between the proposed models and experiments was carried out and results showed good matching. Nevertheless, it is important that a biomass powder simulation addresses overlapping/complicated sub-process. During biomass powder combustion, tar was shown to be formed at a rate of 57 wt.%, and, accordingly, the formation and thermal decomposition of tar were modelled in the study, with the results demonstrating that the tar was formed and then disintegrated at temperatures between 700 and 1050 K. Through biomass powder combustion, moisture, tar, and gases were released, mostly from one lateral of particles, which caused ejection of the solid particles. These new phenomena were investigated experimentally and modeled as well. Results also showed that all the proposed models, along with their rate constants, activation energies, and other models’ parameters, were capable of reproducing the mass yields of gases, tar, and char at a wide range of working temperatures. The results showed that the gasification/devolatilization model 3 is somewhat simple and economical in the simulation/computation scheme, however, models 1 and 2 are rather computationally heavy and complicated.

Investigations of the Influence of Ignition on the Dynamic Vivacity of Propellants

The paper presents an attempt to determine the dynamic vivacity functions of propellants with taking into account a parallel burning of the black powder igniter and the tested propellant. The approach is based on presented results of closed vessel tests, proving that the burning of the tested propellant starts before complete burning of the black powder igniter. Basing on closed vessel tests results for black powder, its dynamic vivacity function was determined. It was used for a prediction of the partial pressure of black powder combustion products in the case when black powder was used as an igniter. Dynamic vivacity curves are compared with the dynamic vivacity curves calculated at the assumption that the combustion of the main charge starts after the complete burning of the igniter. Obtained results show that the considered approach fails due to a very complex interaction between the igniter and the tested propellant.