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1

Unravelling the Effect of Anthraquinone Metal Salts as Wide-range Plateau Catalysts to Enhance the Combustion Properties of Solid Propellants

Wang Y., Yan Q.-L., An T., Chen B., Ji Y.-P., Wang W., Zhao F.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 2

376--390

EN

Novel lead and copper salts based on anthraquinone, including 1,8-dihydroxyanthraquinone,1,4,5,8-tetrahydroxyanthraquinone and 1,8-dihydroxy-4,5-dinitroanthraquinone, were prepared and characterized by Fourier transform infrared spectroscopy (FTIR), elemental analysis (EA), and X-ray fluorescence (XRF). The catalytic effects of these compounds on the decomposition of nitrocellulose (NC) and on the combustion properties of double-base (DB) and composite modified double-base (CMDB) propellants were comprehensively investigated. The results demonstrated that the burning rate is significantly increased (by 200%) in the lower pressure range (2-6 MPa) as compared to the control systems without added anthraquinone-based salts. Concurrently, the pressure exponents (n) were obviously lower, exhibiting a “wide-range plateau” combustion phenomenon in the middle-pressure region. Specifically, for the DB propellants such a plateau region extended from 10 MPa to 16 MPa for n equal to 0.10, from 10 MPa to 18 MPa for n equal to 0.11 and from 8 MPa to 18 MPa when n is 0.05. In the case of RDX-CMDB propellants, the plateau was found to be in the range 6-18 MPa, with n in the range 0.16-0.27, depending on the type of catalyst, in contrast to the reference CMDB sample, which was characterized by n equal to 0.7 for the same pressure range.

2

Synthesis, Characterization, and Application of Stabilized-Ni/Fe Bimetallic Nanoparticles for the Selective Elimination of Chlorate Impurity in Military Grade Ammonium Perchlorate

Zarei A. R., Moloudi A., Hosseini S. G.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 1

120--133

EN

Ammonium perchlorate (AP) is used as the most common oxidizer in composite solid propellants. Control of chlorate impurity in military grade ammonium perchlorate is important, since it has an undesirable effect on the thermal decomposition of ammonium perchlorate. In this work stabilized Ni/Fe bimetallic nanoparticles (S-Ni/Fe NPs) were synthesized using the borohydride reduction method (BRM) in the presence of starch as a stabilizing agent, and they were characterized by field emission scanning electron microscopy (SEM), and their X-ray diffraction pattern (XRD). The results showed that the synthesized S-Ni/Fe bimetallic nanoparticles were spherical in shape and had nearly uniform distribution, with particle sizes of 20-50 nm. The prepared nanoparticles were then used for the selective elimination of chlorate impurity in ammonium perchlorate. The main factors controlling the elimination of chlorate, such as the initial pH of the solution, dosage of S-Fe/Ni NPs, initial chlorate and perchlorate concentrations, reaction temperature, and reaction time, were optimized by using an experimental design based on the Taguchi method. An L9 orthogonal array (L9-OA) was used to design experiments with four 4-level factors (34). Under the optimal conditions, i.e., pH 6.5, at 30 °C and a dosage of 50 mg S-Ni/Fe NPs, chlorate was eliminated with nearly 100% efficiency in 50 mL of a solution containing 2.0 μg·mL−1 and 100 μg·mL−1 of chlorate and perchlorate, respectively, without change in perchlorate concentration.

3

Experimental Study on Ammonium Nitrate(V)-based Solid Propellants for Fracturing Wells

Hadzik J., Koślik P., Wilk Z., Frodyma A., Habera Ł.

Central European Journal of Energetic Materials

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2017

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Vol. 14, no. 3

660--674

EN

This paper investigates the possibility of using ammonium nitrate(V)-based solid propellants for fracturing wells in borehole mining. Various modified propellant compositions with ammonium nitrate(V) and polyurethanes were prepared. Using laboratory rocket motors (LRMs) and underwater tests in pressure chambers, the energetic parameters (i.e., maximum pressure of the gaseous products and pressure impulse) for the selected AN-propellants were determined. Furthermore, thermodynamic analyses for these propellants were performed. The influence of the proposed additives on the energetic parameters (i.e., calorific value and specific energy) was shown. The gas volume generated per unit volume of propellant, which is an important parameter in the process of hydraulic fracturing, was estimated.

4

Modelling of the Viscoplastic Behaviour of Homogeneous Solid Propellants

Pyrz M., Zalewski R.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 1

159--174

EN

This study is concerned with the mechanical properties of homogenous solid propellants. The experimental results demonstrate the high strain rate sensitivity of these materials. A modified viscoplastic model of the Bodner- Partom type was applied to simulate the nonlinear behaviour of solid propellants when subjected to uni-axial loading conditions. The material parameters of the constitutive law were identified numerically using the evolutionary algorithm. The capability of the proposed approach was investigated for a representative solid fuel sample. The efficiency of the method is discussed.

5

Komponenty niejednorodnych stałych paliw rakietowych

Florczak B.

Przemysł Chemiczny

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2011

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T. 90, nr 12

2164-2169

6

Analysis of Uniaxial Tensile Tests for Homogeneous Solid Propellants under Various Loading Conditions

Zalewski R., Wolszakiewicz T.

Central European Journal of Energetic Materials

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2011

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Vol. 8, nr 4

223-231

EN

The main object of this paper is to reveal basic response of solid rocket fuels to different working conditions such as variable strain rates or temperature. Experimental data acquired during experimental tests is a base for development of a suitable constitutive model for homogeneous solid propellants. In the world literature there is still insuffcient information about typical mechanical features for considered materials. Universal standards for carrying out typical strength experiments have not yet been fully elaborated for this type of materials. Such problems as quasi-static strain range for solid propellants or so called scale effect are still not standardized. Though, this paper is a next step in preliminary investigation devoted to modeling of nonlinear properties of solid propellants. In particular, the infuence of temperature and strain rate on selected mechanical parameters variations is discussed.

7

Detection and measurement of fatigue cracks in solid rocket propellants

Giesko T., Boroński D., Zbrowski A., Czajka P.

Problemy Eksploatacji

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2009

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nr 3

75-84

EN

A method and machine vision system capable of automated crack detection and measurement have been developed for fatigue tests on solid rocket propellants under mechanical and thermal stresses. In image analysis and crack detection, the digital image correlation method (DIC) was used. Examples of crack images acquired using the developed system are presented.

PL

W artykule zaprezentowano metodę i system maszynowego widzenia do automatycznej detekcji i pomiarów pęknięcia w stałych paliwach rakietowych poddawanych obciążeniom mechanicznym i termicznym w trakcie badań zmęczeniowych. W opracowanym systemie do analizy obrazów i wykrywania pęknięć zastosowano metodę cyfrowej korelacji obrazów (DIC). Przedstawiono przykładowe obrazy pęknięć zarejestrowane za pomocą opracowanego systemu.