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1

Thermal Decomposition of Ammonium Perchlorate Encapsulated with Copper(II)/Iron(III) Oxide Nanoparticles

Gržetić Jelena D., Mijatov Slavko, Fidanovski Bojana, Kovačević Tihomir, Pavlović Vladimir B., Brzić Saša, Bajić Danica

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 2

114-137

EN

Thermal decomposition of ammonium perchlorate (AP), as a high energy oxidizer in composite solid rocket propellants (CSRP), greatly affects the burning rate of the propellant. This paper summarizes the results of a study of the synergistic catalytic activity of nano-CuO/Fe₂O₃ nanoparticles on thermal decomposition of AP. AP micro-particles are efficiently encapsulated with 1 and 5 wt.% of nano-CuO and/or nano-Fe₂O₃ nanoparticles by the fast-crash solventantisolvent technique. The efficiency of the encapsulation method was confirmed using FT-IR spectroscopy. Morphological characterization, performed using SEM-EDS microscopy, showed that encapsulation provides recrystallization and deagglomeration of AP and uniform nano-catalyst distribution. The catalytic efficiency of nano-CuO/ nano-Fe₂O₃ nanoparticles on the thermal decomposition of AP was investigated using DSC, and an increase in released heat was observed from 1453 to 1628 J/g. The catalytic activities of performed nano-catalysts were proven by decreasing the HTD and merging with the low decomposition temperature peak. The highest catalytic effect was obtained after encapsulating with 5 wt.% of nano-CuO and nano-Fe₂O₃ combined in a 50/50 mass ratio due to multiple mechanisms of catalytic activity of nano-Fe₂O₃. The effect of AP encapsulation with nano-Fe₂O₃ on the burning rate of CSRP was investigated and the obtained results showed a favorable effect on the combustion rate law.

2

Finite Volume Method for the Combustion Reaction of Energetic Materials

Yu Yanchun, Fu Qiang, Ma Jingxin, Chen Weidong, Yan Han

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 2

159--199

EN

In order to analyse the effects of launch on the internal structure due to launch and given the relative paucity of experimental tests in this regime numerical simulations are an important method of prediction. Viscoelastic statistical crack mechanics offer a solution to the dynamic damage problems of explosives involved in explosion, impact and collision. Most finite element software does not include a viscoelastic statistical crack constitutive model; the model can only be embedded in the finite element software. Therefore, a computer program based on the finite volume method combined with viscoelastic statistical crack mechanics is presented, aiming to analyze the explosion problems more precisely and conveniently. A combustion equation of state is proposed to study the combustion reaction of explosives; the trends of temperature and stress of explosive during the combustion process are studied; Hot spot zones formed inside explosives are analyzed. The results are in accordance with the reaction law of combustion. The results indicate that when the bottom of the explosive charge is heated to a certain temperature, the explosive charge have a combustion reaction occurs. This conclusion has important value for studying the effect of the base gap on the launch safety of explosive munitions.

3

Explosive Coordination Materials : Acyclic Ligands - Review

Rećko Judyta

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 4

365--378

EN

Coordination explosives form a significant group of energetic materials, which are mainly considered as novel primary explosives. Due to their modular structure, these compounds offer many possibilities for modifying their physicochemical and energetic properties. In this review the properties of complexes containing molecules such as ammonia, hydrazine, ethylenediamine, carbohydrazide, and guanidine derivatives are presented. The types of ligands and their influence on the physicochemical properties and detonation parameters are discussed.

4

Anisotropic Interfacial Adhesion between Fluoropolymers and RDX Single Crystal Faces

Liu Jiahui, Zhou Xiaoqing, Qian Wen, Gong Feiyan, Yang Zhijian, Li Hongzheng, Nie Fude

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 4

409--423

EN

Interfacial interactions have an important influence on the properties of energetic materials. The anisotropy of interfacial adhesive strength between various 1,3,5-trinitro-1,3,5-triazinane (RDX) single crystal faces and a typical binder was studied in this work by experimental and theoretical investigations. An RDX single crystal was prepared and processed into three kinds of orientated crystal faces, including (002), (020) and (210). These crystal slices were used as substrates, and fluorinated polymer F2314 was used as a binder. The surfaces of the RDX slices were analyzed by X-ray photoelectron spectroscopy (XPS) and an atomic force microscope (AFM). The work of adhesion was obtained from direct tensile tests, using designed samples of the sandwich structure of RDX-F2314-RDX, with various RDX single crystal surfaces. The polarity component of the surface energy and the work of adhesion was obtained by Young’s equation and the Fowkes theory, based on surface contact angle tests. The results in this work indicated the anisotropy of the interfacial adhesion of F2314 on various RDX crystal faces.

5

A Study of a Protective Container for Combined Blast, Fragmentation and Thermal Effects from Energetic Materials Detonation

Ahmed Khurshid, Malik Abdul Qadeer

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 2

135--157

EN

A composite protective container is experimentally investigated to counter combined blast, fragmentation and thermal effects from either a 1.0 kg bare or 0.6 kg cased (pipe-bomb) TNT equivalent charge. Commercially available shaving foam was used as the internal filling material. The shaving foam quenched the initial fireball and afterburning reactions. The composite case contained the blast overpressure and prevented the escape of primary fragments. The novel combination of extended polystyrene (EPS) foam, bakelite and polyurethane (PU)-silica composite employed at the container base provided protection against in-contact explosive detonation. Maximum peak reflected overpressure of 86.87 kPa (12.6 psi) was measured at 1.0 m distance for 1.0 kg TNT equivalent charge detonation inside the container. The protective container provided 97% peak overpressure reduction compared to the equivalent surface burst detonation. The fragmentation and their impact on container were simulated using a coupled SPH-ALE approach. Steel casing fragments weighing up to 8.0 g with velocities in the range of 1260-1550 m/s were produced and impacted the container. This investigation provides a basis in the design of a device to combat terrorist devices in public places, high profile meeting venues and transportation systems.

6

Review of Nano-thermites: a Pathway to Enhanced Energetic Materials

Zaky Mohamed Gaber, Elbeih Ahmed, Elshenawy Tamer

Central European Journal of Energetic Materials

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2021

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Vol. 18, no. 1

63--85

EN

Nano-thermites or metastable intermolecular composites (MICs) have been implemented into modern research on energetic materials as they offer much higher energy densities, higher rates of energy release, stability, and safety (lower sensitivity). This paper reviews several synthetic methods for MICs that have been well thought-out for energetic applications, advantages and disadvantages, as well as the characteristics of each manufacturing technique. The techniques presented include powder mixing, sol-gel, synthesis of MICs based on nano-porous silicon (Psi), sputtering, multilayer nano-foils and electrolytically plated carbon nano-materials for nano-thermite applications. These techniques offer enormously different characteristics and, through the variation of various chemical techniques and conditions, a wide range of chemical and energetic properties may be attained. This may give the opportunity for the safe use of MICs as replacements for some conventional energetic materials in various applications, and may also enable us to study the effects when incorporating these MICs into energetic matrixes, as a promising and feasible research field.

7

Effect of Drying Conditions on the Characteristics and Performance of B/Fe2O3 Nano-Composites Prepared by Sol-Gel Method

Dinçer Yilmaz Nil Ezgi, Karakaş Gürkan

Central European Journal of Energetic Materials

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2020

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Vol. 17, no. 1

85--106

EN

B/Fe2O3 samples were prepared by mixing nano sized boron powder with iron oxide xerogels that had been synthesized using a sol-gel method that included various types of proton scavengers such as 1,2-epoxybutane, tetrahydrofuran, 1,4-dioxane and ammonium hydroxide. The effects of the proton scavengers and drying conditions on the textural properties of the iron oxide samples and on the heat output and thermal behavior of the nano-composites were examined. The iron oxide samples were subjected to direct drying (DD) or sequential solvent exchange (SSE). The heat output values of the B/Fe2O3 nano-composites varied from 240 to 1200 J/g depending on the drying condition and the proton scavenger used. It was found that the thermal behaviour and the textural properties of B/Fe2O3 nano-composites (such as porosity, surface area and crystallinity) could be tailored by both the drying conditions and the proton scavenger used.

8

Pre-formulation Compatibility Studies of 5-Amino-1H-tetrazole Nitrate with Several Typical Materials by Thermal and Non-thermal Techniques

Guo W., Han Z., Lin Q., Wang B.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

100--114

EN

The aim of the present study was to assess the physicochemical compatibility of a promising energetic salt, 5-amino-1H-tetrazole nitrate (5-ATN), with some typical materials. Thermal techniques (differential scanning calorimetry (DSC) and vacuum stability test (VST)) and non-thermal techniques (X-ray diffractometry (XRD) and Fourier Transform Infrared Spectroscopy (FTIR)) were applied. Five energetic materials (TNT, RDX, HMX, CL-20 and AP) and three common additives (Al, DOS and F2604-2) were tested to evaluate their compatibility with 5-ATN. Based on the DSC results, except for AP that was only partially compatible with 5-ATN, all of the selected materials exhibited good compatible with 5-ATN. The VST test further confirmed the compatibility of the 5-ATN/AP mixtures. Combined with the thermal methods, the FTIR results agreed with the DSC findings. The XRD results showed some differences.

9

Fabrication of Nano- and Micron- Sized Spheres of CL-20 by Electrospray

Yan S., Li M., Sun L., Jiao Q., Huang R.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 4

572--589

EN

The application of hexanitrohexaazaisowurtzitane (CL-20) in energetic materials will be expanded by its use as superfine particles. A method of fabricating nano- and micron-sized spheres of CL-20 by using electrospray is discussed. The effects of the precursor solution and the experimental conditions on the morphology and the crystal phase of the CL-20 particles are introduced. A variety of solvents was used to dissolve raw CL-20 for the preparation of the precursor solution with different CL-20 contents. The conductivity and viscosity of the precursor solutions were tested before the electrospray process. The electrostatic parameters were adjusted by changing the voltage and the distance between the nozzle and the plate. The morphology, crystal phase, mechanical sensitivity, density, and thermal stability of the raw CL-20 and the as-sprayed CL-20 samples were determined using scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry (DSC). Furthermore, the density and the mechanical sensitivity were tested for the raw and the as-sprayed CL-20. DSC tests were conducted to compare the thermal stability and reactivity of the samples.

10

Effect of Coated Ammonium Dinitramide on the Properties of Nitrate-ester Plasticized Polyether Solid Rocket Propellants

Pang W. Q., Li J. Q., DeLuca L. T., Ke W., Fu X. L., Zhong F. X., Li H., Ji Y. P.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 4

590--609

EN

Several industrial and research types of nitrate-ester plasticized polyether (NEPE) solid propellants were experimentally analyzed. In general, their compositions differed in the mass fraction of ammonium dinitramide (ADN), which was used as a promising highly energetic filler, as an alternative to ammonium perchlorate (AP). ADN exhibits high performance, low signature and non-polluting characteristics. The propellant composition without ADN, but with AP, was used as the reference. The microstructure and granularity distribution of the uncoated and coated ADN particles were experimentally analyzed. It was found that uncoated ADN particles exhibited irregular shape, while the ADN particles after coating are spherical. Because of their irregular shape, uncoated ADN particles caused inferior processability of the propellant slurry when added to the propellant formulation. Consequently, the NEPE propellants with coated ADN were studied in further detail. The rheological properties, energetic properties, mechanical sensitivities and combustion properties (burning rate and pressure exponent) of the NEPE propellants with coated ADN were studied and compared with the reference NEPE propellant. The addition of ADN particles to the propellant formulations increased the standard theoretical specific impulse and heat of explosion of the propellants, while decreasing the density. The propellants containing ADN particles were much more sensitive to impact and friction compared to the reference sample. Moreover, increasing the ADN mass fraction in the propellant formulation can significantly affect the combustion behaviour and increase the burning rate and pressure exponent compared to of the reference formulation. However it appears that ADN is a very promising candidate as a new energetic material in compositions of NEPE propellants, although several important questions concerning ADN’s suitability, especially in the context of its sensitivity to friction and impact, remain to be answered.

11

4-Amino-3-hydrazino-1,2,4-triazole: a Precursor for the Preparation of Divalent Energetic Materials

Lin Q., Wang P., Sun Q., Lu M.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

18--29

EN

4-Amino-3-hydrazino-1,2,4-triazole (AHT) was developed as a divalent cation. The multivalent structure can be used to increase the number of nitrogen-rich heterocycles, thereby increasing the heat of formation and improving the detonation performance. Herein we report on a family of divalent energetic salts, which exhibit excellent properties, viz. acceptable density, good detonation performance, and desirable thermal and impact stabilities. The structural features of the salts were further determined by single-crystal X-ray diffraction. In addition, the detonation properties calculated for these energetic salts identified them as competitively energetic compounds.

12

The Relationship between Impact Sensitivity of Nitroaromatic Energetic Compounds and their Electrostatic Sensitivity

Zohari N., Seyed-Sadjadi S. A., Marashi-Manesh S.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 2

427--443

EN

This study presents a linear relationship between the impact sensitivity of nitroaromatic energetic compounds and their electric spark sensitivity. The methodology assumes that the impact sensitivity of a nitroaromatic energetic compound with the general formula CaHbNcOd can be expressed as a function of the electrostatic sensitivity, the number of NH2 group substitutions in the 2,4,6-trinitrophenyl ring and non-additive structural parameters. The root mean square and absolute standard deviation of a newly introduced correlation were respectively found to be 2.4 and 2.0 for 27 nitroaromatic energetic compounds. The proposed new correlation was also tested for 7 additional nitroaromatic energetic compounds, which have complex molecular structures such as 1-(2,4,6-trinitrophenyl)-5,7-dinitrobenzotriazole and 1,3,7,9-tetranitrophenoxazine.

13

Research on a New Synthesis of LLM-105 Using N-Nitroso-bis(cyanomethyl)amine

Jing S., Liu Y., Liu D., Guo J.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 1

21--32

EN

A new three-step synthetic method was designed to prepare 2,6-diamino- 3,5-dinitropyrazine 1-oxide (LLM-105) with an overall yield of 43.5%, using iminodiacetonitrile, triethylamine and hydroxylamine hydrochloride as the starting materials, and involved nitrosylation, cyclization and nitration. The structure of LLM-105 was characterized by FTIR, 1H NMR spectroscopy and elemental analysis. The crucial factors and mechanism of the cyclization were explored. Thermal decomposition, mechanical sensitivity and the purity of the LLM-105 were determined by TG-DTA, an impact sensitivity instrument and high performance liquid chromatography (HPLC) respectively. The results showed that LLM-105 synthesised via 2,6-diamino-3,5-dinitropyrazine (ANPZ) was less sensitive to impact, but the LLM-105 synthesized by the new method had some obvious advantages in terms of purity, security and production costs. Moreover, the LLM-105 synthesized by this new method can be initiated reliably without recrystallization.

14

Environmental Long Term Impact on a Romanian Military Testing Range

Petre R., Rotariu T., Zecheru T., Petrea N., Băjenaru S.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 1

3--19

EN

Military range management has become extremely important in recent years, in order to comply with the limitations imposed by national and international environmental regulations. In this regard, soil, vegetation and ground water samples from a testing facility belonging to the Romanian Ministry of National Defense were analyzed for contamination with metals and energetic materials. The tests confirmed the presence of contaminants as energetic materials and heavy metals (Pb, Cu, Zn), with a heterogeneous distribution on the range and concentrated in the impact and firing line areas.

15

Compatibility Study of 2,6-Diamino-3,5-dinitropyridine-1-oxide with Some Energetic Materials

Li X., Wang B.-L, Lin Q.-H.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 4

978--988

EN

For the application of 2,6-diamino-3,5-dinitropyridine-1-oxide (ANPyO) in composite explosives, the compatibility of ANPyO with some energetic materials was studied by the use of differential scanning calorimetry (DSC), where the energetic materials were cyclotrimethylenetrinitramine (RDX), cyclotetramethylenetetranitramine (HMX), 3,4-dinitrofurazanfuroxan (DNTF), hexanitrohexazaisowurtzitane (CL-20), 2,4,6-trinitrotoluene (TNT), 2,4,6-triamino-1,3,5-trinitrobenzene (TATB), 3-nitro-1,2,4-triazol-5-one (NTO), 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105), 5-amino-1H-tetrazole nitrate (5-ATEZN), ammonium perchlorate (AP), potassium perchlorate (KP), aluminum powder (Al), boron powder (B), magnesium hydride (MgH2) and magnesium borohydride (Mg(BH4)2). The results showed that the binary systems of ANPyO/CL-20, ANPyO/NTO, ANPyO/5-ATEZN, ANPyO/Al, ANPyO/B, ANPyO/MgH2 and ANPyO/Mg(BH4)2 are compatible, and that the systems of ANPyO with RDX, LLM-105, HMX, AP and KP are sensitive, and with DNTF, TNT and TATB are incompatible.

16

Nowe technologie na kongresie w Turcji, 19–23 października 2015 r., Oludeniz, Fethiye, Turcja

Wiśniewski P., Wiśniewski P.

Szkło i Ceramika

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2015

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R. 66, nr 6

42

17

Procesy wydobycia oraz transportu ropy naftowej i gazu ziemnego w wybranych krajach UE

Mindur M.

Logistyka

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2015

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nr 4

1435--1444, CD2

PL

W artykule zaprezentowano kształtowanie się zasobów surowców energetycznych na świecie, ze szczególnym ich uwzględnieniem w Europie, oraz zależność wybranych państw UE od importu tych surowców. Omówiono technologie wydobycia ropy naftowej i gazu ziemnego, a także budowę rurociągów i przemieszczanie ładunków. Wskazano zasady finansowania transportu rurociągowego. Analizie poddano politykę energetyczną UE w zakresie perspektyw zmniejszenia jej uzależnienia od importu surowców energetycznych.

EN

The formation of the energetic raw material resources in the world, and particularly in Europe, and the dependence of the chosen states of the EU on import of these raw materials were presented in this article. The technologies for extraction of a crude oil and a natural gas and construction of pipelines and some dislocations of loads was also discussed in this article. There were indicated in it also the principles for financing the pipeline transport. The energetic policy of the EU within the domain of prospects for reduction of dependence of this policy on the import of energetic raw materials was subject to an analysis in this article.

18

Preparation and Characterization of 1-(5-Azido-1H-1,2,4-triazol-3-yl)tetrazole

Izsák D., Klapötke T. M.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 3

403--416

EN

This study presents the preparation of 1-(5-azido-1H-1,2,4-triazol-3yl)tetrazole (5) from commercially available chemicals in a five step synthesis. The energetic title compound was comprehensively characterized by various means, including vibrational (IR, Raman) and multinuclear (1H, 13C, 14N, 15N) NMR spectroscopy, mass spectrometry and differential scanning calorimetry. The sensitivities towards various outer stimuli (impact, friction) were determined according to BAM standards. The enthalpy of formation was calculated at the CBS-4M level of theory.

19

Influence of Technological Parameters on the Combustion Velocity of Pyrotechnic Compositions for Gas Generator of Base Bleed Projectiles

Pašagić S., Antonović D., Brzić S.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 2

331--346

EN

The specific purpose of a pyrotechnic mixture for a Gas Generator (GG) of Base Bleed (BB) projectile requires a carefully balanced combustion velocity for obtaining the maximum projectile range and avoiding a reactive propelling force. The development of the pyrotechnic element is done under laboratory conditions which often differ from the real usage conditions. To be able to fairly predict the combustion process characteristics in the real GGs of BB projectiles, some influential technological factors and their influence on the combustion velocity have been investigated. Factors which were observed to have the most significant influence on the combustion velocity of pyrotechnic compositions are charge density, oxygen balance, combustion chamber wall thickness and material type. Individual and combined influence of these factors on the combustion velocity will also be presented in this paper.

20

Influence of Copper Wire Heat Guides on the Combustion Velocity of Organic Based Charges for Gas Generators of Base Bleed Projectiles

Pasagić S., Antonović D., Sirovatka R., Petković J.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 3

563--577

EN

Organic fuel based pyrotechnic charges for gas generators (GG) of Base Bleed (BB) projectiles have shown better combustion characteristics than metallic based ones. Since organic fuel based compositions are representative of energy poor pyrotechnic mixtures, they combust at lower combustion velocities. Conventional methods for heat transfer enhancement of GG charges, based on the introduction of metallic fuel components into pyrotechnic mixtures, are very successful in raising the combustion velocity, but inevitably, they also tend to force production of solid and liquid combustion products which reduce the GG charge’s functionality. In this paper, the results obtained by inserting copper wires (copper wire heat guides (HG)) into organic-based gas generator charges will be presented. The aim of inserting copper wires was to enhance the combustion velocity by influencing on the thermal heat transfer of GG charges. The results have shown that copper wire heat guides had a positive influence on the GG charges heat transfer, resulting in a 15-20% rise in the combustion velocity, without any of the side effects observed in the case of the addition of metallic fuels to GG charges.