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

2019 ◽  
Vol 9 (4) ◽  
pp. 1-14
Author(s):  
Radosław TRĘBIŃSKI ◽  
Zbigniew LECIEJEWSKI ◽  
Zbigniew SURMA
Keyword(s):  
Partial Pressure ◽  
Combustion Products ◽  
Complex Interaction ◽  
Closed Vessel ◽  
Black Powder ◽  
Main Charge ◽  
Powder Combustion

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.

scholarly journals The Effect of the Temperature and Moisture to the Permeation Properties of PEO-Based Membranes for Carbon-Dioxide Separation

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2053
Author(s):  
Dragutin Nedeljkovic
Keyword(s):  
Carbon Dioxide ◽  
Partial Pressure ◽  
Carbon Dioxide Emission ◽  
Combustion Products ◽  
Mixed Matrix Membranes ◽  
Mixed Matrix Membrane ◽  
Mixed Matrix ◽  
Gas Treatment ◽  
Carbon Dioxide Separation ◽  
Different Temperatures

An increased demand for energy in recent decades has caused an increase in the emissions of combustion products, among which carbon-dioxide is the most harmful. As carbon-dioxide induces negative environmental effects, like global warming and the greenhouse effect, a decrease of the carbon-dioxide emission has emerged as one of the most urgent tasks in engineering. In this work, the possibility for the application of the polymer-based, dense, mixed matrix membranes for flue gas treatment was tested. The task was to test a potential decrease in the permeability and selectivity of a mixed-matrix membrane in the presence of moisture and at elevated temperature. Membranes are based on two different poly(ethylene oxide)-based polymers filled with two different zeolite powders (ITR and IWS). An additive of detergent type was added to improve the contact properties between the zeolite and polymer matrix. The measurements were performed at three different temperatures (30, 60, and 90 °C) under wet conditions, with partial pressure of the water equal to the vapor pressure of the water at the given temperature. The permeability of carbon-dioxide, hydrogen, nitrogen, and oxygen was measured, and the selectivity of the carbon-dioxide versus other gases was determined. Obtained results have shown that an increase of temperature and partial pressure of the vapor slightly increase both the selectivity and permeability of the synthesized membranes. It was also shown that the addition of the zeolite powder increases the permeability of carbon-dioxide while maintaining the selectivity, compared to hydrogen, oxygen, and nitrogen.

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

2021 ◽  
pp. 53-57
Author(s):  
V. Kozachuk ◽  
M. Sliusarenko
Keyword(s):  
Combustion Products ◽  
The Other ◽  
Light Sources ◽  
Current Value ◽  
Precision And Accuracy ◽  
Shell Particles ◽  
The Military ◽  
Parameter Values ◽  
The Impact ◽  
Powder Combustion

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.

Understanding Interior Ballistic Processes in a Flash Tube

2010 ◽  
Vol 77 (5) ◽  
Author(s):  
Ryan W. Houim ◽  
Kenneth K. Kuo
Keyword(s):  
Shock Wave ◽  
Combustion Products ◽  
Wall Friction ◽  
Normal Shock ◽  
Black Powder ◽  
Normal Shock Wave ◽  
Weapon Systems ◽  
Flash Tube ◽  
Pressure Distributions ◽  
Pressure Profiles

Vented flash tubes have often been used in the ignition train of medium and large caliber weapon systems. Despite their long history of ballistic usage, there are undesirable features associated with uneven venting of the combustion products. Pressure measurements at various locations from the flash tube have shown severe variations with time, which is associated with spatially nonuniform mass discharging rate from the vent holes. Measured pressure profiles in the flash tube show counterintuitive, nonmonotonic pressure distributions with the lowest pressure in the middle of the venting section of the flash tube. A model of the flash tube venting process was developed to explain these phenomena using modern, high-order numerical schemes. Source terms accounting for mass addition from the black powder pellets, mass loss through the vent holes, wall friction, differential area changes, and volume changes from surface regression of black powder pellets were fully coupled in the model. The numerical results of this model reproduced the severe pressure variations and nonmonotonic pressure profiles observed in experiments. In general, they are caused by gas dynamic effects from a slowly moving normal shock wave in the middle portion of the venting section of the flash tube. As the driving pressure from the burning black powder pellets changes, the location of the normal shock wave jumps from one vent hole set to another, producing pressure variations observed in experiments. The physical understanding gained from this model solution has provided guidance for achieving more uniform mass discharging rate by varying the vent hole sizes as a function of distance along the flash tube.

Effect of Black Powder Combustion on High- and Low-Pressure Igniter Systems

1981 ◽  
Author(s):  
Kevin J. White ◽  
Hughes E. Holmes ◽  
John R. Kelso
Keyword(s):  
Low Pressure ◽  
Black Powder ◽  
Powder Combustion

Numerical Modeling of Formation of High-Speed Water Slugs

2002 ◽  
Author(s):  
O. Petrenko ◽  
E. S. Geskin ◽  
G. A. Atanov ◽  
A. Semko ◽  
G. A. B. Goldenberg
Keyword(s):  
High Speed ◽  
Energy Exchange ◽  
Stationary Process ◽  
Combustion Products ◽  
High Rate ◽  
Water Load ◽  
Pressure Distributions ◽  
Pressure Fields ◽  
Design Characteristics ◽  
Powder Combustion

The objective of this study is to investigate the phenomena that occur in the course of energy injection into water at an extremely high rate. In this study energy was injected via the powder explosion. In the course of this study a numerical model was constructed and used for process investigation. The model describes powder combustion, energy exchange between combustion products and the water load, formation of the shock waves in the water and superposition of waves. It was assumed that powder combustion is a stationary process, and the description of this process was used to determine the variation of the pressure exerted on the water. The 1D space approximation was used for description of the dynamics of the water motion. The velocity and pressure fields were determined for a fixed instant of time. The characteristic method was used to relate the velocity and pressure distributions in the instants t and t+Δt. The pressure, velocity and density fields in the course of slug formation were calculated and used to evaluate the design characteristics of the device for water acceleration termed the water cannon.

scholarly journals Determination of environmental burden of combustion products of pyrotechnic mixtures to quarrying operations

2019 ◽  
pp. 78-87
Author(s):  
Andrzej Maranda ◽  
Rostyslav Zrobok ◽  
Bogdan Florczak ◽  
Bożena Kukfisz
Keyword(s):  
Environmental Impact ◽  
Thermodynamic Parameters ◽  
Impact Analysis ◽  
Combustion Products ◽  
Environmental Impact Analysis ◽  
Black Powder ◽  
Environmental Burden ◽  
Pyrotechnic Mixtures

Using the ICT-Thermodynamic Code program, thermodynamic parameters and combustion products composition of the Rocksplitter type, containing different masses of pytotechnic mixture and black powder, were evaluated. The eco-indicator was determined on the basis of numerical falsification results obtained using the SimaPro PhD version 7.2 of the Dutch company PreConsultants. The environmental impact analysis was performed at the combustion temperatures of the tested mixtures and at 298 K.

Analysis of the chemical composition of powder combustion products in the nonstationary mode

1976 ◽  
Vol 12 (6) ◽  
pp. 826-827
Author(s):  
Yu. A. Gostintsev ◽  
S. S. Novikov ◽  
L. N. Stesik ◽  
L. A. Sukhanov
Keyword(s):  
Chemical Composition ◽  
Combustion Products ◽  
Powder Combustion
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