Computational Code for Detonation Spraying Process

1998 ◽  
Author(s):  
T.P. Gavrilenko ◽  
Y.A. Nikolaev ◽  
V.Y. Ulianitsky ◽  
M.C. Kim ◽  
J.W. Hong
Keyword(s):  
Gaseous Mixture ◽  
Gaseous Detonation ◽  
Powder Injection ◽  
Powder Materials ◽  
Productivity Analysis ◽  
Detonation Spraying ◽  
Injection Point ◽  
High Productivity ◽  
Product Flow ◽  
Computational Code

Abstract Interactive Computational Code is presented that provides a high-productivity analysis of the complex detonation spraying technology. It is based on exact gas dynamics theory taking into account chemical reactions for description of the gaseous detonation phenomena. It deals with specific features of the process like non-homogeneity of gaseous mixture compositions due to gas filling operation and powder injection into the barrel. Acceleration and heating of powder particles by the detonation product flow were simulated including particle melting, fragmentation and vaporization. Calculations for different fuels and powder materials were accomplished. Optimum conditions (gas mixture, barrel length, powder injection point, etc.) to provide highest velocity and appropriate temperature for typical metal and cermet powders are discussed. The conditions for coating formation by the detonation gun «Ob» were established and samples were produced. Experimental data on detonation coating properties are presented to prove the theoretical results.

scholarly journals Получение наноразмерного детонационного углерода на импульсном газодетонационном аппарате

2018 ◽  
Vol 44 (9) ◽  
pp. 65
Author(s):  
А.А. Штерцер ◽  
В.Ю. Ульяницкий ◽  
И.С. Батраев ◽  
Д.К. Рыбин
Keyword(s):  
Gaseous Mixture ◽  
Particle Morphology ◽  
Industrial Safety ◽  
Flow Mode ◽  
Detonation Spraying ◽  
Gas Detonation ◽  
High Productivity ◽  
Carbon Combustion ◽  
Forms Of Carbon ◽  
Gas Supply

AbstractCombustion and thermal decomposition of hydrocarbon fuels are used to produce different forms of carbon. Combustion in the detonation mode is of particular interest, as nanocarbon obtained under these conditions differs in properties from products synthesized by other techniques. A pulsed gas-detonation device designed on the basis of a CCDS2000 detonation spraying facility opens up new possibilities for manufacturing of nanocarbon. The device operates in a flow mode of gas supply into the reactor at the atmospheric pressure, which ensures high productivity and industrial safety of this method. Using detonation of acetylene-oxygen mixtures rich in acetylene, nanoscale carbon was obtained with particle morphology depending on the ratio of the components in the gaseous mixture.

Application of Overdriven Gaseous Detonation for Spraying

1998 ◽  
Author(s):  
T.P. Gavrilenko ◽  
Y.A. Nikolaev ◽  
V.Y. Ulianitsky
Keyword(s):  
Surface Coating ◽  
Internal Surface ◽  
Gaseous Detonation ◽  
Detonation Waves ◽  
Powder Materials ◽  
High Melting ◽  
Detonation Products ◽  
Detonation Spraying ◽  
High Melting Temperature ◽  
Overdriven Detonation

Abstract The use of overdriven detonation waves can promote coating fabrication from powder materials with high melting temperature and improve the quality coating for all materials. The detonation products flow behind overdriven detonation has kinetic and thermal energy values significantly exceeding those for self-sustaining Chapman- Jouguet's detonation, conventionally used for detonation spraying. This makes it possible to design a micro-gun and, as a consequence, the equipment for internal surface coating.

scholarly journals Influence of gas detonation spraying parameters on the geometrical structure of Fe-Al intermetallic protective coatings

2019 ◽  
Author(s):  
Tomasz Chrostek ◽  
Mirosław Bramowicz ◽  
Kazimierz Rychlik ◽  
Wojtkowiak Adam ◽  
Cezary Senderowski
Keyword(s):  
Fractal Dimension ◽  
Geometric Structure ◽  
Geometrical Structure ◽  
Protective Coatings ◽  
Sampling Rate ◽  
Roughness Parameter ◽  
Powder Injection ◽  
Science Center ◽  
Detonation Spraying ◽  
Gas Detonation

The paper presents the results of an investigation and analysis of the geometrical structure of Fe-Al intermetallic protective coatings sprayed under specified gun detonation spraying (GDS) conditions. As GDS variable parameters there were applied two different barrel lengths and two powder injection position (PIP) at the moment of spark detonation as well as two different number of GDS shots with 6.66 Hz frequency. The measurements of the surface's profile were carried out through means of contact profilometry, in which case TOPO-01 system and Mitutoyo SJ 210 profilometer were applied. On the basis of the measurements conducted the analysis of in two-dimensional (2D) and spatial (3D) systems was made possible. The authors assumed that roughness can be considered as a non-stationary parameter of variance of surface amplitude, which is highly dependent on the sampling rate and length of an elementary segments. Therefore, the changes in the amplitude parameters and functional properties of the surface at different lengths of measuring segments (ln), respectively: 1.25, 4 and 12.5 mm, were analyzed. In the analysis of the degree of development of the geometric structure of the surface, the RMS (Root Mean Square) fractal method was used, with an assessment of the geometric structure of the surface stretched over several size levels, taking into account the correlation between the roughness parameter Rq, the measuring length (ln) and the fractal dimension (D). The application of the RMS method with the determination of the fractal dimension (D) allowed for the characterization of the geometric structure of intermetallic Fe-Al protective coatings detonation sprayed under specific conditions of the GDS process - based on the surface roughness profiles of different measured length (ln). Research undertaken within the framework of project No. 2015/19 / B / ST8 / 02000 subsidized by the National Science Center of Poland.

High productivity analysis of 15N and 13C in soil/plant research

1995 ◽  
pp. 43-59
Author(s):  
A. Barrie ◽  
S. T. Brookes ◽  
S. J. Prosser ◽  
S. Debney
Keyword(s):  
Productivity Analysis ◽  
High Productivity ◽  
Plant Research

Productivity Analysis of Public Services

2010 ◽  
pp. 83-105
Author(s):  
Aki Jääskeläinen ◽  
Paula Kujansivu ◽  
Jaani Väisänen
Keyword(s):  
Data Mining ◽  
Public Service ◽  
Day Care ◽  
Productivity Analysis ◽  
Day Care Centers ◽  
High Productivity ◽  
Public Service Organizations ◽  
Care Services ◽  
Child Day Care ◽  
Service Productivity

Productivity is a key success factor in any organization. In order to improve productivity, it is necessary to understand how various factors affect it. The previous research has mainly focused on productivity analysis at macro level (e.g. nations) or in private companies. Instead, there is a lack of knowledge about productivity drivers in public service organizations. This study aims to scrutinize the role of various operational (micro level) factors in improving public service productivity. In particular, this study focuses on child day care services. First, the drivers of productivity are identified in light of the existing literature and of the results of workshop discussions. Second, the drivers most conducive to high productivity and the specific driver combinations associated with high productivity are defined by applying methods of data mining. The empirical data includes information on 239 day care centers of the City of Helsinki, Finland. According to the data mining results, the factors most conducive to high productivity are the following: proper use of employee resources, efficient utilization of premises, high employee competence, large size of day care centers, and customers with little need for additional support.

Effects of Water Temperatures on Water-Soluble Binder Removal in Ceramic Materials Fabricated by Powder Injection Moulding

2015 ◽  
Vol 659 ◽  
pp. 90-95
Author(s):  
Wantanee Buggakupta ◽  
Nutthita Chuankrerkkul ◽  
Juthathep Surawattana
Keyword(s):  
Injection Moulding ◽  
Removal Rate ◽  
Ceramic Powder ◽  
Polyvinyl Butyral ◽  
Ceramic Materials ◽  
Water Soluble ◽  
Powder Injection ◽  
Powder Materials ◽  
Binder Removal ◽  
Powder Injection Moulding

This work focuses on the debinding conditions of the ceramic materials fabricated by powder injection moulding. Ceramic powder materials, including alumina and alumina-based composites were prepared as feedstocks and mixed with water-soluble polyethylene glycol (PEG) and polyvinyl butyral (PVB). The PEG/PVB binder mixture, with PEG to PVB ratio of 85:15 by weight and powder loading of 44 vol%, were thoroughly mixed and injected into the mould at the temperature of 190 °C to obtain rod-like specimens. Prior to sintering, the as-injected specimen was then leached in water, the temperature of which was varying from 30 (ambient temperature), 45 to 60 °C, in order to get rid of PEG and leave the specimens in shape by PVB. The rate of PEG removal according to different water temperatures was investigated. The experimental results suggested that PEG could completely be eliminated by 45 and 60 °C water without any dimensional disintegration in 5 hours whereas those leached in 30 °C water showed only 70% PEG removal. Higher water temperatures led to fast PEG removal rate at the beginning and then gradually decreased with elapsed times.

scholarly journals Numerical Simulation of Liquid-Fueled Detonations by an Eulerian–Lagrangian Model

2012 ◽  
Vol 13 (2) ◽  
pp. 177-188
Author(s):  
Hua Shen ◽  
Gang Wang ◽  
Kaixin Liu ◽  
Deliang Zhang
Keyword(s):  
Detonation Velocity ◽  
Propagation Velocity ◽  
Gaseous Mixture ◽  
Numerical Results ◽  
Gaseous Detonation ◽  
Lagrangian Model ◽  
Detonation Waves ◽  
Phase System ◽  
Two Phase ◽  
Droplet Sizes

Abstract In this paper, an Eulerian–Lagrangian two-phase flow model for liquid-fueled detonations is constructed. The gaseous mixture is described by an Eulerian method, and liquid particles in gaseous mixture are traced by a Lagrangian method. An improved space-time conservation element and solution element (CE/SE) scheme is applied to the simulations of detonations in liquid C 10 H 22 -O 2 /air systems. Different fuel droplet sizes and equivalence ratios are considered in the present study. Interestingly, the numerical results show that liquid-fueled detonations have some difference with gaseous detonations. Especially, a deficit in the propagation velocity compared to the gaseous detonation velocity is observed in mixtures with lean fuel and larger droplet sizes, while an increase in the propagation velocity compared to the gaseous detonation velocity is observed in the mixtures with very rich fuel. The surprising phenomenon is analyzed and discussed with the aid of detailed numerical results. In addition, the formation and propagation of two-phase detonation waves are characterized by series of results and the influence of particle radii is also discussed. All numerical results show that the present model can describe the gas-particle two-phase system accurately, and can be applied to numerical simulations of liquid-fueled detonations.

High productivity analysis of15N and13C in soil/plant research

1995 ◽  
Vol 42 (1-3) ◽  
pp. 43-59 ◽  
Author(s):  
A. Barrie ◽  
S. T. Brookes ◽  
S. J. Prosser ◽  
S. Debney
Keyword(s):  
Productivity Analysis ◽  
High Productivity ◽  
Plant Research

scholarly journals Preparation and Characterization of NiCr/NiCr-Al2O3/Al2O3 Multilayer Gradient Coatings by Gas Detonation Spraying

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1524
Author(s):  
Bauyrzhan Rakhadilov ◽  
Dastan Buitkenov ◽  
Zhuldyz Sagdoldina ◽  
Zhanat Idrisheva ◽  
Manira Zhamanbayeva ◽  
...  
Keyword(s):  
Phase Composition ◽  
Ceramic Layer ◽  
Oxygen Mixture ◽  
Gas Mixture ◽  
Powder Materials ◽  
Detonation Spraying ◽  
Mixture Ratio ◽  
Gun Barrel ◽  
Detonation Gun ◽  
Gradient Coatings

This paper investigates the influence of the technological parameters of detonation spraying on the phase composition of NiCr- and Al2O3-based coatings. It was determined that the phase composition of Al2O3 coatings during detonation spraying strongly depends on the barrel filling volume with the gas mixture. The acetylene–oxygen mixture, which is the most frequently used fuel in the detonation spraying of powder materials, was used as a fuel gas. To obtain a ceramic layer based on Al2O3, spraying was performed at an acetylene–oxygen O2/C2H2 mixture ratio of 1.856; the volume of filling of the detonation gun barrel with an explosive gas mixture was 63%. To obtain a NiCr-based metallic layer, spraying was performed at the O2/C2H2 ratio of 1.063; the volume of filling of the detonation gun barrel with an explosive gas mixture was 54%. Based on a study of the effect of the detonation spraying mode on the phase composition of NiCr and Al2O3 coatings, NiCr/NiCr-Al2O3/Al2O3-based multilayer coatings were obtained. Mixtures of NiCr/Al2O3 powders with different component ratios were used to obtain multilayer gradient coatings. The structural-phase composition, mechanical and tribological properties of multilayer gradient metal–ceramic coatings in which the content of the ceramic phase changes smoothly along the depth were experimentally investigated. Three-, five- and six-layer gradient coatings were obtained by alternating metallic (NiCr) and ceramic (Al2O3) layers. The phase composition of all coatings was found to correspond to the removal of information from a depth of 20–30 μm. It was determined that the five-layer gradient coating, consisting of the lower metal layer (NiCr), the upper ceramic layer (Al2O3) and the transition layer of the mechanical mixture of metal and ceramics, is characterized by significantly higher hardness (15.9 GPa), wear resistance and adhesion strength.

Sign in / Sign up

Export Citation Format

Share Document