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1

Theoretical analysis of the use of glycidyl polyazide and polynitratomethylmethyloxetane in high-performance reduced-smoke rocket propellants

Gołofit Tomasz, Cieślak Katarzyna, Chmielarek Michał

Materiały Wysokoenergetyczne

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2023

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T. 15

36--47

EN

Conducting preliminary calculations of the ballistic effectiveness and smoke generation of new rocket propellant compositions is beneficial due to the high cost of tests. In this work, the combustion temperature (Tcomb.) and specific impulse (Isp) for rocket propellants were determined using the Air Force Specific Impulse Program. The effect of replacing the non-energetic binder hydroxyl terminated polybutadiene (HTPB) with binders containing explosophoric groups with glycidyl polyazide (GAP) or polynitratomethylmethyloxetane (polyNIMMO), and replacing ammonium perchlorate (AP) with ammonium dinitramide (ADN) are discussed. The highest Tcomb. and the highest Isp were obtained for a system containing 20% GAP, 60% ADN and 20% Al. Another important aspect of modern rocket propellants is smoke intensity, so smoke classifications were determined for the proposed compositions in accordance to the classification given in a report by the Advisory Group for Aerospace Research & Development (AGARD). The use of the new components – GAP, polyNIMMO and ADN – is beneficial because it enables a higher Isp and reduced smoke. The maximum Isp of these propellants is obtained for compositions containing higher amounts of binder, which facilitates the manufacturing process. The use of computer calculations in the first phase of research into new rocket propellants makes it possible to estimate the improvement in performance of the new propellant and to learn about the impact of composition changes on performance.

PL

Przeprowadzenie wstępnych obliczeń efektywności balistycznej oraz dymności nowych składów paliw rakietowych jest korzystne ze względu na wysokie koszty badań gotowych wyrobów. W pracy, przy wykorzystaniu programu Air Force Specific Impulse Program wyznaczono temperaturę palenia (Tcomb.) i impuls właściwy (Isp) układów trójskładnikowych zawierających jako utleniacz: chloran(VII) amonu (AP), sól amonową dinitroaminy (ADN), jak lepiszcze: polibutadien zakończony grupami hydroksylowymi (HTPB), poliazydek glicydylu (GAP), poliazotanometylometyloksyetan (NIMMO) oraz glin (Al). Omówiono wpływ zastąpienia nieenergetycznego lepiszcza HTPB, lepiszczami zawierającymi grupy eksplozoforowe oraz zastąpienie AP ADN. Opisano również wpływ Al na temperaturę i Isp omawianych paliw. Najwyższą Tcomb. oraz najwyższy Isp uzyskano dla układu GAP-ADN-Al. Kolejnym istotnym aspektem nowoczesnych paliw rakietowych jest intensywność dymienia. Określono klasy dymienia według klasyfikacji AGARD zaproponowanych składów. Zastosowanie nowych składników GAP, NIMMO i ADN jest korzystne, ponieważ: pozwala na uzyskanie większego Isp oraz zmniejszonego dymienia. Maksimum Isp tych paliw jest uzyskiwane dla składów zawierających większe ilości lepiszcza, co ułatwia proces wytwarzania. Wykorzystanie obliczeń komputerowych w pierwszym etapie badań nad nowymi paliwami rakietowymi pozwala na oszacowanie poprawy parametrów użytkowych nowego paliwa oraz poznanie wpływu zmian składu na parametry użytkowe.

2

Computational Determination of the Specific Impulse of Solid Rocket Propellant Compositions of closo-Dodecaborate ([B₁₂H₁₂]2‒) Salts with HTPB Binder and Ammonium Perchlorate as an Oxidizer

Rao Muddamarri Hanumantha

Central European Journal of Energetic Materials

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2023

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Vol. 20, no. 4

386--399

EN

Boron (B) powder in elemental form is a very attractive high-energy material and it is a metalloid chemical element. B powder has the second highest heat of explosion of any element that can be adopted as an energetic material in dealing with propellants and explosives. In practical situations, B has problems with ignition and combustion due to the formation of a B₂O₃ layer on its surface. B cannot burn easily; it requires ultra-pure oxygen during the combustion process and also undergoes agglomeration due to which incomplete combustion of the B particles in the propellant composition occurs. Hence in order to address these issues, we introduced closo-dodecaborate ([B₁₂H₁₂]2‒) salts into a solid rocket propellant composition instead of B powder. In the present work, three solid rocket propellant compositions based on closo-dodecaborate salts were theoretically investigated. The specific impulse (Isp) was calculated for three closo-dodecaborate [B₁₂H₁₂]2‒ based propellant compositions using the EXPLO5 code version V6.03. The performance values of the closo-dodecaborate [B₁₂H₁₂]2‒ salts based propellant compositions were compared with those of pure aluminium (Al)-based composite propellant. Using the EXPLO5 code (V6.03); hydroxyl-terminated polybutadiene (HTPB) and ammonium perchlorate (NH₄ClO₄, AP) were used as binder and oxidizer respectively. closo-Dodecaborate salts-HTPB-AP formulations have good theoretical performance; it was observed that the presence of a closo-dodecaborate salt in the propellant composition can lead to very good performance, and they are potential candidates as fuels and/or fuel additives in propellant compositions for missile and rocket applications.

3

Research Output Software for Energetic Materials Based on Observational Modelling 2.2 (RoseBoom2.2©) - Update to Calculate the Specific Impulse, Detonation Velocity, Detonation Pressure and Density for CHNO Mixtures Using the Supersloth-function

Klapötke Thomas M., Wahler Sabrina

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 3

295--310

EN

RoseBoom2.2© can calculate parameters for CHNO mixtures, automatically minimizing user-input. In the present study, RoseBoom’s© results were compared to 518 EXPLO5 calculations. The new version of RoseBoom© can calculate a variety of parameters for mixtures. The detonation pressure and detonation velocity, and the specific impulse were calculated using different methods. In the present study different approaches for calculating the average sum formula have been evaluated

4

Ammonium Dodecahydrododecaborate (NH4)2[B12H12]: Hydrogen and Boron Rich Fuel for Jet Propulsion Engines

Jadhav Pandurang M., Patil Jay, Prasanth Hima, Rao Gururaja

Central European Journal of Energetic Materials

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2022

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Vol. 19, no. 2

158--167

EN

There is dire need for the exploration of boron (B) substitution in jet propulsion engines for improving their combustion characteristics. In this regard, ammonium dodecahydrododecaborate (NH4)2[B12H12] has been synthesized, characterized and evaluated for its propulsion characteristics. This hydrogen and boron-rich entity was found to be a potential candidate for future applications in propulsion technology.

5

A Theoretical Study of Polyethylene Glycol Polynitrates as Potential Highly Energetic Plasticizers for Propellants

Wang Guixiang, Xu Yimin, Zhang Wenjing, Gong Xuedong

Central European Journal of Energetic Materials

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2019

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Vol. 16, no. 2

194--215

EN

Polyethylene glycol polynitrates may be used as plasticizers in propellants. In this study, ten derivatives of ethylene glycol dinitrate were investigated using the density functional theory method. The fitted densities (ρ’exp.) were obtained and were very close to the experimental values. The detonation properties were predicted using the modified Kamlet-Jacobs equations and the specific impulse (Is) was evaluated according to the largest exothermic principle. A new indicator, K = Is · ρ’exp., is proposed to evaluate the energetic characteristics of the plasticizers. Thermal stability is discussed by calculating the bond dissociation energies or energy barriers. The O−NO2 bond is the trigger bond for all of the compounds studied. Considering the energetic properties and stability, diethylene glycol tetranitrate, triethylene glycol hexanitrate, tetraethylene glycol octanitrate, pentaethylene glycol decanitrate and hexaethylene glycol dodecanitrate are potential energetic plasticizers for solid propellants. The influences of the −O−CH2−CH2− and −O−CH(ONO2)−CH(ONO2)− groups are also discussed, which will be helpful for the design of new highly energetic plasticizers by modifying the structures as required.

6

A thermodynamic study on catalytic decomposition of hydrazine in a space thruster

Pakdehi Shahram, Shirvani Fatemeh, Zolfaghari Reihaneh

Archives of Thermodynamics

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2019

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Vol. 40, no 4

151--166

EN

Most satellites stationed in space use catalytic propulsion systems for attitude control and orbit adjustment. Hydrazine is consumed extensively as liquid monopropellant, in the thrusters. Catalytic reactor is the most important section in the catalytic thruster. Ammonia and nitrogen gases are produced as a result of complete catalytic decomposition of hydrazine in the reactor, causing an increase in temperature and a rise in specific impulse. Ammonia is subsequently decomposed, leading to nitrogen and hydrogen gases. Decomposition of ammonia leads to a decrease in temperature, molecular weight and specific impulse. The latter phenomenon is unavoidable. The effect of ammonia decomposition on the reactor temperature, molecular weight of gaseous products and conclusively on specific impulse was studied in this article. At adiabatic state, thermodynamic analysis revealed that the maximum and minimum temperatures were 1655 K and 773 K, respectively. The highest molecular weight was obtained at ammonia conversion of zero and the lowest when ammonia conversion was 100%. The maximum specific impulse (305.4 S) was obtained at ammonia conversion of zero and completely conversion of ammonia, the minimum specific impulse (about 213.7 s) was obtained. For specific impulse, the result of thermodynamic calculation in this work was validated by the empirical results.

7

Investigation of the Radical Nitration of Isooctane Fuel via Nitromethane Propellant

Bayar C. C.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 2

225--242

EN

The possible radical nitration reactions of isooctane fuel with nitromethane propellant, which is generally used as an additive in fuel formulations, were thermodynamically investigated both at room temperature and at a higher temperature of 691.15 K. The temperature of 691.15 K was chosen because it is the auto-ignition temperature of isooctane and nitromethane and has the potential to mimic better engine conditions. The computational calculations were performed at the theoretical level of DFT UB3LYP/cc-pVDZ. Four different nitration reactions and nitrated products were considered and interpreted in detail. The most and the least favorable nitrations were observed at the primary and secondary carbons of isooctane at 691.15 K, respectively. Four of the designated reactions were endothermic at this temperature. The other outcome of this study was that there was a direct relationship between the thermodynamic tendencies of the considered reactions and the ballistic performances (detonation velocities, detonation pressures, and specific impulses) of their nitrated products. The thermodynamic properties of heats of combustion and deflagration temperatures were calculated via empirical formulations based on the stoichiometry and some other structural parameters of the energetic materials. The results for nitromethane and the nitro-isooctane products were examined.

8

Effect of Some Inorganic Nitrate Salts on the Ignition Delay Time of DMAZ-IRFNA and DMAZ-WFNA Bi-propellants

Pakdehi S. G., Shirzadi B.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 1

162--174

EN

Dimethylaminoethyl azide (DMAZ) is a good replacement for the hydrazine group in the space industry. However, it has a relatively long ignition delay time with the liquid oxidizer, white fuming nitric acid (WFNA), and is nonhypergolic with inhibited red fuming nitric acid (IRFNA). In this article, the ignition delay times of DMAZ-WFNA and DMAZ-IRFNA bi-propellants were reduced by the addition of some inorganic nitrate salts, such as NH4NO3, KNO3, NaNO3, AgNO3 and LiNO3, to the liquid oxidizers. The results showed that WFNA containing 0.1 wt.%, 0.3 wt.% and 0.5 wt.% of LiNO3 reduced the ignition delay time of DMAZ-WFNA from 88 ms to 18 ms, 14 ms and 8 ms, respectively. The same percentages of LiNO3 caused the nonhypergolic DMAZ-IRFNA bi-propellant to have ignition delay times of 42 ms, 34 ms and 22 ms, respectively. Moreover, calculations indicated that the addition of LiNO3 to both oxidizers did not have a significant affect on the specific impulse of the bi-propellants. Consequently LiNO3 could be an appropriate additive for the reduction of the ignition delay times of DMAZ-WFNA and DMAZ-IRFNA bi-propellants.

9

Optimal design of a composite propellant formulation using response surface methodology

Hamed J. O., Ogunleye O. O., Osheku C. A.

Advances in Materials Science

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2017

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Vol. 17, nr 1(51)

44--57

EN

There is a continuous demand for high performance composite propellant formulations to meet mission requirements. The performance of composite propellant formulations can be enhanced by optimizing propellant formulation. However, the main objective of this study is to formulate a composition for composite propellant by optimizing the specific impulse which is the measure of propellant performance. A central composite design (ccd) consisting five ingredients (ammonium nitrate, powdered aluminum, polyester resin, ammonium dichromate and powdered charcoal) at five levels was used to formulate optimum propellant formulation from composite materials of ammonium nitrate based propellant verified for propellant characteristics using propellant performance evaluation programme (propep 3). The responses evaluated are specific impulse, characteristic velocity, density, temperature and molecular weight. Response surface methodology was used to analyze the results of the ccd of the composite formulations. The optimum values for specific impulse, characteristic velocity, density, temperature and molecular weight of the mixture from the surface plot are 212.178 s, 1335.81 m/s, 1640.6 k g/m3, 1968.73 k and 21.7722 g/mol respectively. The optimum predicted specific impulse was 212.178 s at composite composition of 73.61% ammonium nitrate, 4.36% powdered aluminum, 14.39% polyester resin, 5.10% ammonium dichromate and 2.54% powdered charcoal. The propellant optimum composition validated with propep 3 are in good agreement with each other in their accompany propellant characteristics. Therefore, the optimal propellant formulation enhanced the performance of solid propellants.

10

Quantitative Variations Resulting from the Gradual Replacement of NO2 with NF2-fragments in Energetic Materials

Lempert D. B., Dorofeenko E. M.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 1

35--46

EN

A thermodynamic analysis of the energetic parameters and the combustion products of model energetic systems based on the mixture tetranitromethane + tetra(difluoramino)methane as oxidizer, and combustible components (either polyethylene, or carbon, or boron, or decaborane) has been accomplished. The optimal ratios between the components for achieving the maximal specific impulse have been found. The nature of the combustion products, the dependence of their distribution on the percentage of the components, and how the distribution of the combustion products influences the specific impulse value, have been studied.

11

Optimization of potassium nitrate based solid propellant grains formulation using response surface methodology

Ogunleye O O, Hammed J O, Alagbe S O

Advances in Science and Technology. Research Journal

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2015

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Vol. 9, nr 27

123--134

EN

This study was designed to evaluate the effect of propellant formulation and geometry on the solid propellant grains internal ballistic performance using core, bates, rod and tubular and end-burn geometries. Response Surface Methodology (RSM) was used to analyze and optimize the effect of sucrose, potassium nitrate and carbon on the chamber pressure, temperature, thrust and specific impulse of the solid propellant grains through Central Composite Design (CCD) of the experiment. An increase in potassium nitrate increased the specific impulse while an increase in sucrose and carbon decreased specific impulse. The coefficient of determination (R2) for models of chamber pressure, temperature, thrust and specific impulse in terms of composition and geometry were 0.9737, 0.9984, 0.9745 and 0.9589, respectively. The optimum specific impulse of 127.89 s, pressure (462201 Pa), temperature (1618.3 K) and thrust (834.83 N) were obtained using 0.584 kg of sucrose, 1.364 kg of potassium nitrate and 0.052 kg of carbon as well as bate geometry. There was no significant difference between the calculated and experimented ballistic properties at p < 0.05. The bate grain geometry is more efficient for minimizing the oscillatory pressure in the combustion chamber.

12

Rozwój ekologicznych silników rakietowych na ciekłe materiały pędne

Florczuk W., Kublik D., Sobczak K.

Prace Instytutu Lotnictwa

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2014

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Nr 1 (234) March 2014

62--72

PL

W artykule zawarto zestawienie i omówienie ekologicznych materiałów pędnych będących obecnie tematem najliczniejszych publikacji w zakresie badań nad ciekłymi rakietowymi materiałami pędnymi stanowiącymi realną alternatywę dla obecnie stosowanych mieszanin typu MMH/MON, UDMH/NTO, czy hydrazyna. Należą do nich ADN, HAN, HNF oraz HTP. Dodatkowo, przedstawione zostały programy badań kosmicznych, gdzie jako źródło napędu platform satelitarnych zastosowanie znalazły opisane ekologiczne materiały pędne. Przedstawiono również wyzwania stojące przed konstruktorami pracującymi nad silnikami na ciekłe materiały pędne, a także trendy dotyczące ich przyszłych zastosowań.

EN

This article contains the survey of the non-toxic, environment friendly and low cost, green propellants being intensively investigated by the space propulsion communities. These propellants represent compounds with the highest potential to be used as an alternatives for the mixture of MMH/MON, UDMH/NTO or hydrazine in monopropellant propulsion. They include ADN, HAN, HNF and HTP. Additionally, the newest space missions with the utilization of the green propellants in their ACS (Attitude Control Systems) were described. The new challenges for the design and determination of the current trends in the field of development of the liquid rocket engines are also included.

13

Energetic Performances of Solid Composite Propellants

Lempert D., Nechiporenko G., Manelis G.

Central European Journal of Energetic Materials

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2011

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Vol. 8, nr 1

25-38

EN

Different kinds of solid composite propellant (SCP) are described. All ways to increase energetic potential of SCP are considered as well as pro et contra of each of these ways. Different kinds of oxidizer (perchlorates of ammonium, hydroxylammonium, and hydrazinium; ammonium salt of dinitramine; other saltlike and molecular oxidizers) are under consideration. The main principles creation of SCP formulation with optimal characteristics in the context of their concrete purpose are discussed, e.g. for rockets with considerably low ratio propellant volume/empty construction mass (V/M lower than 1 Litr/kg or so) the ballistic effectiveness may be increased with the replacement of aluminum by high-dense zirconium or zirconium hydride. Possibilities for creation of special SCP formulations for application at the far space, e.g. for Mars exploration are discussed as well.

14

Geometry and electric power effects on specific impulse and efficiency of an arc-jet thruster

Kamińska A., Białek A., Dudeck M.

Journal of Technical Physics

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2008

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Vol. 49, no 2

101-112

EN

The properties of an argon D.C. arc-jet thruster for space propulsion functioning at low electric power (around 10 kW) and low mass flow (0.5 g/s) are determined. The physical description of the arc and jet plasma takes into account non-equilibrium conditions for local kinetic temperatures and ionization effect. The plasma properties (velocity, pressure, electron and heavy particles temperatures and densities) are calculated by a Navier-Stokes modeling. The influence of different plasma source geometry such as angle and length of the nozzle divergent part and electric power on thrust, specific impulse and arc-jet efficiency are discussed.

15

Energetic Characteristics of Solid Composite Propellants and Ways for Energy Increasing

Lempert D. B., Nechiporenko G. N., Manelis G. B.

Central European Journal of Energetic Materials

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2006

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Vol. 3, nr 4

73-87

EN

Energetic characteristics of solid composite propellants of different type and application are described - metal-free compositions containing an oxidizer and a fuel-binder only; compositions containing additionally an energetic compound (Al, Be, Mg, B), metal hydrides (AlH3, BeH2, BxNyHz). A considerable attention is attracted to analysis of oxidizers (ammonium perchlorate, hydroxylammonium perchlorate, ammonium dinitramide etc) because oxidizer occupies the greatest mass fraction in propellant and mostly that is the oxidizer that determines energetic characteristics of the propellant. The main principles of the using of different kinds of binder are considered. It was shown that the competence to choose the binder to the given oxidizer can increase considerably the energetic characteristics even without creation of new compounds. Ways to optimize solid composite propellants destined for missile complexes of different mass characteristics are described. Different ways to further development of solid composite propellants are presented - optimization of formulations basing on accessible components; creation of new more effective binders, having additional functions of oxidizer or gasifying component etc. Ecological problems of solid composite propellants are also a topic of the paper. Ways to decrease ecological danger while solid composite propellants using are investigated.