Articoli di riviste: "Composite propellant"

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Abdullah, Mohamed, F. Gholamian e A. R. Zarei. "Noncrystalline Binder Based Composite Propellant". ISRN Aerospace Engineering 2013 (24 settembre 2013): 1–6. http://dx.doi.org/10.1155/2013/679710.

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This study reports on propellants based on cross-linked HTPE binder plasticized with butyl nitroxyethylnitramine (BuNENA) as energetic material and HP 4000D as noncrystalline prepolymer. This binder was conducted with solid loading in the 85%. The results showed an improvement in processability, mechanical properties and burning rate. In addition, its propellant delivers (about 6 seconds) higher performance (specific impulse) than the best existing composite solid rocket propellant. Thermal analyses have performed by (DSC, TGA). The thermal curves have showed a low glass transition temperature () of propellant samples, and there was no sign of binder polymer crystallization at low temperatures (−50°C). Due to its high molecular weight and unsymmetrical or random molecule distributions, the polyether (HP 4000D) has been enhanced the mechanical properties of propellants binder polymer over a large range of temperatures [−50, 50°C]. The propellants described in this paper have presented high volumetric specific impulse (>500 s·gr·cc−1). These factors combined make BuNENA based composite propellant a potentially attractive alternative for a number of missions demanding composite solid propellants.

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Poryazov, V. A., K. M. Moiseeva e A. Yu Krainov. "NUMERICAL SIMULATION OF COMBUSTION OF THE COMPOSITE SOLID PROPELLANT CONTAINING BIDISPERSED BORON POWDER". Vestnik Tomskogo gosudarstvennogo universiteta. Matematika i mekhanika, n. 72 (2021): 131–39. http://dx.doi.org/10.17223/19988621/72/11.

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A problem of combustion of the composite solid propellants containing various powders of metals and non-metals is relevant in terms of studying the effect of various compositions of powders on the linear rate of propellant combustion. One of the lines of research is to determine the effect of the addition of a boron powder on the burning rate of a composite solid propellant. This work presents the results of numerical simulation of combustion of the composite solid propellant containing bidispersed boron powder. Physical and mathematical formulation of the problem is based on the approaches of the mechanics of two-phase reactive media. To determine the linear burning rate, the Hermance model of combustion of composite solid propellants is used, based on the assumption that the burning rate is determined by mass fluxes of the components outgoing from the propellant surface. The solution is performed numerically using the breakdown of an arbitrary discontinuity algorithm. The dependences of the linear burning rate of the composite solid propellant on the dispersion of the boron particles and gas pressure above the propellant surface are obtained. It is shown that the burning rate of the composite solid propellant with bidispersed boron powder changes in contrast to that of the composite solid propellant with monodispersed powder. This fact proves that the powder dispersion should be taken into account when solving the problems of combustion of the composite solid propellants containing reactive particles.

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Aziz, Amir, Rizalman Mamat, Wan Khairuddin Wan Ali e Mohd Rozi Mohd Perang. "Review on Typical Ingredients for Ammonium Perchlorate Based Solid Propellant". Applied Mechanics and Materials 773-774 (luglio 2015): 470–75. http://dx.doi.org/10.4028/www.scientific.net/amm.773-774.470.

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Ammonium perchlorate (AP) based solid propellant is a modern solid rocket propellant used in various applications. The combustion characteristics of AP based composite propellants were extensively studied by many research scholars to gain higher thrust. The amount of thrust and the thrust profile, which may be obtained from a specific grain design, is mainly determined by the propellant composition and the manufacturing process that produces the solid propellant. This article is intended to review and discuss several aspects of the composition and preparation of the solid rocket propellant. The analysis covers the main ingredients of AP based propellants such as the binder, oxidizer, metal fuel, and plasticizers. The main conclusions are derived from each of its components with specific methods of good manufacturing practices. In conclusion, the AP based solid propellant, like other composite propellants is highly influenced by its composition. However, the quality of the finished grain is mainly due to the manufacturing process.

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Hamed, J. O., O. O. Ogunleye e C. A. Osheku. "Optimal design of a composite propellant formulation using response surface methodology". Advances in Materials Science 17, n. 1 (1 marzo 2017): 44–57. http://dx.doi.org/10.1515/adms-2017-0004.

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Abstract 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.

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Kohga, Makoto, Tomoki Naya e Kayoko Okamoto. "Burning Characteristics of Ammonium-Nitrate-Based Composite Propellants with a Hydroxyl-Terminated Polybutadiene/Polytetrahydrofuran Blend Binder". International Journal of Aerospace Engineering 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/378483.

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Ammonium-nitrate-(AN-) based composite propellants prepared with a hydroxyl-terminated polybutadiene (HTPB)/polytetrahydrofuran (PTHF) blend binder have unique thermal decomposition characteristics. In this study, the burning characteristics of AN/HTPB/PTHF propellants are investigated. The specific impulse and adiabatic flame temperature of an AN-based propellant theoretically increases with an increase in the proportion of PTHF in the HTPB/PTHF blend. With an AN/HTPB propellant, a solid residue is left on the burning surface of the propellant, and the shape of this residue is similar to that of the propellant. On the other hand, an AN/HTPB/PTHF propellant does not leave a solid residue. The burning rates of the AN/HTPB/PTHF propellant are not markedly different from those of the AN/HTPB propellant because some of the liquefied HTPB/PTHF binder cover the burning surface and impede decomposition and combustion. The burning rates of an AN/HTPB/PTHF propellant with a burning catalyst are higher than those of an AN/HTPB propellant supplemented with a catalyst. The beneficial effect of the blend binder on the burning characteristics is clarified upon the addition of a catalyst. The catalyst suppresses the negative influence of the liquefied binder that covers the burning surface. Thus, HTPB/PTHF blend binders are useful in improving the performance of AN-based propellants.

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Jayaraman, Kandasamy, Ponnurengam Malliappan Sivakumar, Ali Zarrabi, R. Sivakumar e S. Jeyakumar. "Combustion Characteristics of Nanoaluminium-Based Composite Solid Propellants: An Overview". Journal of Chemistry 2021 (19 maggio 2021): 1–12. http://dx.doi.org/10.1155/2021/5520430.

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The nanosized powders have gained attention to produce materials exhibiting novel properties and for developing advanced technologies as well. Nanosized materials exhibit substantially favourable qualities such as improved catalytic activity, augmentation in reactivity, and reduction in melting temperature. Several researchers have pointed out the influence of ultrafine aluminium (∼100 nm) and nanoaluminium (<100 nm) on burning rates of the composite solid propellants comprising AP as the oxidizer. The inclusion of ultrafine aluminium augments the burning rate of the composite propellants by means of aluminium particle’s ignition through the leading edge flames (LEFs) anchoring above the interfaces of coarse AP/binder and the binder/fine AP matrix flames as well. The sandwiches containing 15% of nanoaluminium solid loading in the binder lamina exhibit the burning rate increment of about 20–30%. It was noticed that the burning rate increment with nanoaluminium is around 1.6–2 times with respect to the propellant compositions without aluminium for various pressure ranges and also for different micron-sized aluminium particles in the composition. The addition of nano-Al in the composite propellants washes out the plateaus in burning rate trends that are perceived from non-Al and microaluminized propellants; however, the burning rates of nanoaluminized propellants demonstrate low-pressure exponents at the higher pressure level. The contribution of catalysts towards the burning rate in the nanoaluminized propellants is reduced and is apparent only with nanosized catalysts. The near-surface nanoaluminium ignition and diffusion-limited nano-Al particle combustion contribute heat to the propellant-regressing surface that dominates the burning rate. Quench-collected nanoaluminized propellant residues display notable agglomeration, although a minor percentage of the agglomerates are in the 1–3 µm range; however, these are within 5 µm in size. Percentage of elongation and initial modulus of the propellant are decreased when the coarse AP particles are replaced by aluminium in the propellant composition.

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Yao, Er Gang, Feng Qi Zhao, Si Yu Xu, Rong Zu Hu, Hui Xiang Xu e Hai Xia Hao. "Combustion Characteristics of Composite Solid Propellants Containing Different Coated Aluminum Nanopowders". Advanced Materials Research 924 (aprile 2014): 200–211. http://dx.doi.org/10.4028/www.scientific.net/amr.924.200.

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Aluminum nanopowders coated with oleic acid (nmAl+OA), perfluorotetradecanoic acid (nmAl+PA) and nickel acetylacetonate (nmAl+NA) were prepared. The combustion characteristics of hydroxyl terminated polybutadiene (HTPB) composite solid propellants containing different coated aluminum nanpowders were investigated. The result shows that the burning rate of the propellant sample containing nmAl+NA is the highest at different pressure, the maximum burning rate is up to 26.13 mm·s-1at 15 MPa. The burning rates of propellant samples containing nmAl+OA and nmAl+PA are almost the same at different pressures, and higher than the propellant samples containing untreated aluminum nanopowders only at the pressure range of 10 ~ 15 MPa. The flame brightness of different propellants under different pressure is not the same. The flame brightness is increased with the pressure increasing. The flame center zone brightness of the propellant containing nmAl+PA and nmAl+NA is brighter under 4 MPa, and the brightness of nmAl+NA is the brightest. The surface coating of aluminum nanopowder has little effect on the combustion flame temperature of solid propellant. The burning surface temperature increases with the pressure increasing.

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Runtu, Khevinadya Ramadhani, Wahyu Sri Setiani e Mala Utami. "Application Energetic Materials for Solid Composite Propellant to Support Defense Rocket Development". International Journal of Social Science Research and Review 6, n. 1 (6 gennaio 2023): 153–59. http://dx.doi.org/10.47814/ijssrr.v6i1.756.

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In its application in space technology, solid composite propellants are often used as fuel in rockets for military purposes. Increasing the energy of the propellant is carried out by observing two stages, the use of energetic materials and improvements to the process technology. The current development of propellant technology makes it possible to use new energetic materials, simple formulations, high energy, and smokeless. The purpose of this research is to find out developments related to the use of highly energetic materials as raw materials for composite propellants for defense rockets at the Rocket Technology Research Center, ORPA-BRIN. This study uses qualitative analysis methods with research designs in the literature studies and simulation results. In the context of mastering rocket propellant technology in Indonesia, the application of highly energetic materials is expected to be able to solve the problem of rocket propulsion performance. Currently, the Rocket Technology Research Center, ORPA-BRIN is developing a smokeless propellant composite with a composition based on the energetic materials AP/HTPB/Al and an oxidizing agent RDX. From the results of the combustion simulation software ProPEP and RPA, it shows that the composition of the resulting combustion gaseous (Al2O3 and HCl) shows a decrease when using RDX energetic material-based propellant. It's known that RDX can significantly reduce smoke in propellant combustion products. The application of the new highly energetic materials compound is expected to significantly solve the problem of solid rocket propulsion performance.

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Cui, Huiru, Xuan Lv, Yurong Xu, Zhiwen Zhong, Zixiang Zhou e Weili Ma. "A Step-by-Step Equivalent Microprediction Method for the Mechanical Properties of Composite Solid Propellants considering Dewetting Damage". International Journal of Aerospace Engineering 2022 (14 febbraio 2022): 1–12. http://dx.doi.org/10.1155/2022/2427463.

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Reliable prediction of the macromechanical properties of composite solid propellants in the microscale can accelerate the development of propellants with high mechanical properties. According to the characteristics of the composition ratio of a four-component hydroxyl-terminated polybutadiene (HTPB) propellant with the component ammonium perchlorate (AP), hydroxyl-terminated polybutadiene, aluminum powder (AL), and cyclotrimethylenetrinitramine (or RDX for short), an improved random delivery algorithm was developed to separately model filler particles with the different sizes. A step-by-step equivalent representative volume element (RVE) model was generated to reflect the microstructures of the propellant. The isotropy and uniformity of the RVE model were also tested using a two-point probability function. The Park-Paulino-Roesler (PPR) cohesive model was introduced to simulate the particle debonding (or dewetting) in solid propellant. The stress-strain curves of the propellant were obtained by the macroscopic test with the extension rate 200 mm/min at different temperatures. Based on these experimental data, the 8 characteristic parameters suitable for the microinterface of the propellant were obtained by using an inversion optimization method. A microscale finite element prediction model of the propellant considering dewetting damage was constructed to study the evolution process of the microdamage of the propellant. The predicted stress-strain curves of the propellant under different loading conditions were in good agreement with the test results.

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Junqueira Pimont, Lia, Paula Cristina Gomes Fernandes, Luiz Fernando de Araujo Ferrão, Marcio Yuji Nagamachi e Kamila Pereira Cardoso. "Study on the Mechanical Properties of Solid Composite Propellant Used as a Gas Generator". Journal of Aerospace Technology and Management, n. 1 (21 gennaio 2020): 7–10. http://dx.doi.org/10.5028/jatm.etmq.65.

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A gas generating propellants are used as initiators of liquid rocket propellants turbopumps and have as desired characteristic a high-volume production of low-temperature gas. In this context, some formulations of composite propellant containing polyurethane (based on liquid hydroxyl-terminated polybutadiene), guanidine nitrate, ammonium perchlorate, and additives were evaluated and characterized in order to verify their potential as gas generator propellant, as well as to evaluate the influence of additives on mechanical properties. The formulations were prepared, analyzed, and tested for mechanical properties.

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Trębiński, Radosław, Jacek Janiszewski, Zbigniew Leciejewski, Zbigniew Surma e Kinga Kamińska. "On Influence of Mechanical Properties of Gun Propellants on Their Ballistic Characteristics Determined in Closed Vessel Tests". Materials 13, n. 14 (21 luglio 2020): 3243. http://dx.doi.org/10.3390/ma13143243.

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The geometric burning law of gun propellants is widely used in computer codes used for the simulations of the internal ballistics of guns. However, the results of closed vessel tests prove that the burning process of some propellants deviates from the geometric law. Validation of the hypothesis that observed deviations can be attributed to the cracking of propellant grains was the aim of this work. In order to verify the hypothesis, three types of gun propellants were chosen with considerably differing mechanical strengths: a single-base propellant, a double-base propellant, and a composite propellant. The mechanical properties of the gun propellants were tested using a quasi-static compression method with strain rate values of the order of 0.001 s−1 and the Split Hopkinson Pressure Bar technique with the strain rate in the range of 1000–6000 s−1. The mechanical responses of the propellants were assessed on the basis of the true stress–strain curves obtained and from the point of view of the occurrence of cracks in the propellant grains specimens. Moreover, closed vessel tests were performed to determine experimental shape functions for the considered gun propellants. Juxtaposition of the stress‒strain curves with the experimental shape functions proved that the observed deviations from the geometrical burning law can be attributed mainly to the cracking of propellant grains. The results obtained showed that the rheological properties of propellants are important not only from the point of view of logistical issues but also for the properly controlled burning process of propellants during the shot.

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Bekhouche, Slimane, e Yun Jun Luo. "Research of Formulation and Processing of Hydroxyl-Terminated Polybutadiene (HTPB) Propellants". Advanced Materials Research 1030-1032 (settembre 2014): 155–60. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.155.

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Solid composite propellants are extensively used for propulsion of rockets, missiles and space applications. The composite propellant is a polymeric matrix in which the oxidizer and fuel particles are embedded in a polymeric binder. Different composite propellant mixtures have been prepared using ammonium-perchlorate (ratio 70:30) as oxidant and mixture of aluminium powder (ratio 50:50) as metal component. In the present work, RDX (Cyclotrimethylene trinitramine) has been used in successive increments replacing AP (Ammonium Perchlorate) in number of batches by varying the percentage of solid loading, and studied their different properties such as viscosity build-up, mechanical and ballistic properties.

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Mukhtar, Amir, Habib Nasir e Hizba Waheed. "Pressure-Time Study of Slow Burning Rate Ap/HTPB Based Composite Propellant by Using Closed Vessel Test (CVT)". Key Engineering Materials 778 (settembre 2018): 268–74. http://dx.doi.org/10.4028/www.scientific.net/kem.778.268.

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The Closed vessel (CV) is an equipment used to study the ballistic parameters by recording burning time history, pressure buildup during the process and vivacity of the propellants. It is an apparatus which consists of strong pressure vessel, piezo-electric pressure transducers, sensors and dedicated software. To save time and resources this method is employed instead of dynamic firing while doing research and development of propellants. A measured amount of propellant charge is loaded in the vessel and fired remotely. Ignition is provided by the filament which ignites the black powder charge. In this study, we have used Closed Vessel Tests (CVT) for the first time for recording the ballistic parameters of slow burning composite rocket propellant. We developed a set of composite solid propellant samples containing a mixture of bimodal Ammonium Perchlorate (AP) as an oxidizer, Hydroxy-terminated Polybutadiene (HTPB) as a binder as well as fuel, Dioctyl Sebacate (DOS) as plasticizer, 1-(2-methyl) Aziridinyl Phosphine Oxide (MAPO) as bonding agent and Toluene Diisocyanate (TDI) as curator. Samples were developed by changing the solid loading percentage of bimodal AP particles. By increasing the percentage of AP, the oxidizer-fuel ratio (O/F) increases which effects the ballistic parameters. It is observed that maximum pressure and vivacity increases with increase in solid filler in the propellants. As quantity of AP increases, rate of rise of pressure also increases. CVT firing of each sample was done three times to obtain average burning time and pressure buildup history to evaluate the effect of oxidizer loadings on ballistic parameters of the composite propellant.

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Traissac, Y., J. Ninous, R. Neviere e J. Pouyet. "Mechanical Behavior of a Solid Composite Propellant during Motor Ignition". Rubber Chemistry and Technology 68, n. 1 (1 marzo 1995): 146–57. http://dx.doi.org/10.5254/1.3538726.

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Abstract In order to understand the behavior of composite propellants during motor ignition, a particular study about mechanical and ultimate properties of a Hydroxy-Terminated Polybutadiene (HTPB) filled propellant under superimposed hydrostatic pressure was carried out. The mechanical response of the propellant was obtained for uniaxial tensile and simple shear tests at various temperatures, strain rates and superimposed pressures from atmospheric pressure to 15 MPa. The experimentally observed ultimate properties were found to be strongly pressure sensitive and the data were formalized in a specific stress failure criterion.

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Dostanic, Jasmina, Gordana Uscumlic, Tatjana Volkov-Husovic, Radmila Jancic-Heinemann e Dusan Mijin. "The use of image analysis for the study of interfacial bonding in solid composite propellant". Journal of the Serbian Chemical Society 72, n. 10 (2007): 1023–30. http://dx.doi.org/10.2298/jsc0710023d.

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In the framework of this research, the program Image Pro Plus was applied for determining the polymer-oxidizer interactions in HTPB-based composite propellants. In order to improve the interactions, different bonding agents were used, and their efficiency was analyzed. The determination of the quantity, area and radius of non-bonded oxidizer crystals is presented. The position of formed cracks in the specimen and their area have a great influence on the mechanical properties of composite propellant. The preparation of the composite propellant in order to enable the photographing of their structure by means of stereoscopic and metallographic microscopes with the digital camera is also described as well. .

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Lin, Guomin, Yixue Chang, Yu Chen, Wei Zhang, Yanchun Ye, Yanwen Guo e Shaohua Jin. "Synthesis of a Series of Dual-Functional Chelated Titanate Bonding Agents and Their Application Performances in Composite Solid Propellants". Molecules 25, n. 22 (16 novembre 2020): 5353. http://dx.doi.org/10.3390/molecules25225353.

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Titanate-based bonding agents are a class of efficient bonding agents for improving the mechanical properties of composite solid propellants, a kind of special composite material. However, high solid contents often deteriorate the rheological properties of propellant slurry, which limits the application of bonding agents. To solve this problem, a series of long-chain alkyl chelated titanate binders, N-n-octyl-N, N-dihydroxyethyl-lactic acid-titanate (DLT-8), N-n-dodecyl-N, N-dihydroxyethyl-lactic acid-titanate (DLT-12), N-n-hexadecyl-N, N-Dihydroxyethyl-lactic acid-titanate (DLT-16), were designed and synthesized in the present work. The infrared absorption spectral changes of solid propellants caused by binder coating and adhesion degrees of the bonding agents on the oxidant surface were determined by micro-infrared microscopy (MIR) and X-ray photoelectron spectroscopy (XPS), respectively, to characterize the interaction properties of the bonding agents with oxidants, ammonium perchlorate (AP) and hexogen (RDX), in solid propellants. The further application tests suggest that the bonding agents can effectively interact with the oxidants and effectively improve the mechanical and rheological properties of the four-component hydroxyl-terminated polybutadiene (HTPB) composite solid propellants containing AP and RDX. The agent with longer bond chain length can improve the rheological properties of the propellant slurry more significantly, and the propellant of the best mechanical properties was obtained with DLT-12, consistent with the conclusion obtained in the interfacial interaction study. Our work has provided a new method for simultaneously improving the processing performance and rheological properties of propellants and offered an important guidance for the bonding agent design.

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Dîrloman, Florin Marian, Gabriela Toader, Traian Rotariu, Tudor Viorel Țigănescu, Raluca Elena Ginghină, Răzvan Petre, Florentina Alexe et al. "Novel Polyurethanes Based on Recycled Polyethylene Terephthalate: Synthesis, Characterization, and Formulation of Binders for Environmentally Responsible Rocket Propellants". Polymers 13, n. 21 (5 novembre 2021): 3828. http://dx.doi.org/10.3390/polym13213828.

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Novel polyurethane-based binders, specifically designed for environmentally responsible rocket propellant composites, were obtained by employing the polyester-polyols that resulted from the degradation of polyethylene terephthalate waste. A new class of “greener” rocket propellants, comprising polyurethanes (based on recycled PET) as the binder, phase stabilized ammonium nitrate (PSAN) as the eco-friendly oxidizer, and triethylene glycol dinitrate (TEGDN) as the energetic plasticizer, together with aluminum as fuel and Fe2O3 as the catalyst, is herein reported. The components of the energetic mixtures were investigated (individually and as composite materials) through specific analytical tools: 1H-NMR, FT-IR, SEM-EDX, DTA and TGA, tensile and compression tests, DMA, and micro-CT. Moreover, the feasibility of this innovative solution is sustained by the ballistic performances exhibited by these composite materials in a subscale rocket motor, proving that these new formulations are suitable for rocket propellant applications.

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Chandru, R. A., S. Chappa, R. S. Bharath, C. Oommen e B. N. Raghunandan. "Micro-fibre based Porous Composite Propellants with High Regression Rates". Defence Science Journal 67, n. 3 (25 aprile 2017): 240. http://dx.doi.org/10.14429/dsj.67.10279.

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Harnessing energy at micro-scale from high energy sources has gained significance in recent times for space propulsion and other applications. Conventional solid rocket propellants have advantages in terms of being efficient, compact and safe to handle, though with much lower regression rates as compared to solid explosives. An approach to high regression rates in composite propellants is demonstrated in the present work by the enhancement of fuel-oxidiser interaction, and by the incorporation of micro-scale porosity into the propellant grain. The porous polystyrene-ammonium perchlorate grain designed in this work, based on electrospun micro-fibres and aqueous impregnation, exhibits burning rates more than 25 times as compared to the non-porous grain. Such high regression rates using insensitive propellant compositions have practical implications in the development of micro-thrusters, and in gas generating devices such as MAV launch systems and turbine starters. Detailed preparatory procedure, characterisation techniques, and flame regression studies are included in this paper.

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Wu, Weijing, Haiyang Li, Zhibin Shen e Zijian Fan. "Comparative research on tension-compression mechanical properties of the azide propellant". Journal of Physics: Conference Series 2285, n. 1 (1 giugno 2022): 012024. http://dx.doi.org/10.1088/1742-6596/2285/1/012024.

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Abstract While the azide propellant is a typical particle-reinforced composite material, its mechanical properties are quite different under two different loads of tension and compression. In order to study the possible relationship between the tension and compression mechanical properties of the propellant, so as to further study the loading mechanism of the propellant, this paper carried out constant-rate tension and constant-rate compression tests of the azide propellant and measured the stress-strain curves in different loading case for follow-up comparative study. The mechanical properties of the propellant under different loading rates were analyzed quantitatively, and the differences between the tension and compression stresses of the propellant at different strain rates were quantitatively analyzed, and the change rules of tension-compression mechanical properties of the azide propellant were obtained. The research results can provide the basis for the application analysis of the azide propellant in the engine, and the research method can provide a reference for the tension-compression comparative study of other types of propellants.

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Mukhtar, A., e H. Nasir. "Comparative Closed Vessel Firing-Ballistic Parameters Evaluation for Development of Base Bleed Composite Solid Propellant". Engineering, Technology & Applied Science Research 8, n. 6 (22 dicembre 2018): 3545–49. http://dx.doi.org/10.48084/etasr.2370.

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Closed vessel test (CVT) is widely used for the measurement and comparison of ballistic and energetic properties of propellants by the ignition of a specific sample mass in a closed high-pressure vessel. In our research, comparative CVTs were performed in a vessel, where an internationally accepted composite propellant base bleed grain sample served as a reference (Ref) for recording the standard values of the under investigation propellant composition, in relation to which newly developed samples were characterized. These comparative CVT experiments were performed under chamber volume of 100cm3, sample mass of 10g for all samples and identical ignition system having 1.5g igniter bag of gunpowder. We used closed vessel with working pressure limit of 5000 bars for recording the ballistic parameters of various composite solid propellant samples with reference to a standard sample. It was found that the Ref sample at 50% propellant loading recorded mean maximum pressure (Pm) of 1040 bars in complete combustion time (tPm) of 120ms and vivacity of 0.038 (1/bar∙s). The measured mean Pm was taken as relative force (%) and measured mean vivacity was taken as relative vivacity (%). This data has been used to tune and study the ballistic parameters to develop Ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene (HTPB) based composite solid propellant (CSP) base bleed grain for artillery projectile.

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Brzic, Sasa, Ljiljana Jelisavac, Jela Galovic, Danica Simic e Jelena Petkovic. "Viscoelastic properties of hydroxyl-terminated poly(butadiene) based composite rocket propellants". Chemical Industry 68, n. 4 (2014): 435–43. http://dx.doi.org/10.2298/hemind130426067b.

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In the present study, the viscoelastic response of three composite solid propellants based on hydroxyl-terminated poly(butadiene), ammonium perchlorate and aluminum has been investigated. The investigation was surveyed by dynamic mechanical analysis over a wide range of temperatures and frequencies. The mechanical properties of these materials are related to the macromolecular structure of the binder as well as to the content and nature of solid fillers. The storage modulus, loss modulus, loss factor and glass transition temperature for each propellant sample have been evaluated. The master curves of storage (log G' vs log ?) and loss modulus (log G'' vs log ?) were generated for each propellant. A comparison of logaT vs temperature curves for all propellants indicate conformance to Williams-Landel-Ferry equation. Choosing the glass transition as the reference temperature, WLF equation constants are determined. Fractional free volume at the glass transition temperature and thermal coefficient of free volume expansion values are in accordance with the consideration that Al is reinforcing filler.

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Yang, Yi, Xinjie Yu, Jun Wang e Yaxue Wang. "Effect of the Dispersibility of Nano-CuO Catalyst on Heat Releasing of AP/HTPB Propellant". Journal of Nanomaterials 2011 (2011): 1–5. http://dx.doi.org/10.1155/2011/180896.

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Abstract (sommario):

Kneading time is adjusted to change the dispersibility of nano-CuO in AP/HTPB (Ammonia Perchlorate/Hydroxyl-Terminated Polybutadiene) composite propellants. Nano-CuO/AP is prepared to serve as the other dispersing method of nano-CuO, named predispersing procedure. Several kinds of heat releasing, thermal decomposition by DSC, combustion heat in oxygen environment, and explosion heat in nitrogen environment, are characterized to learn the effect of dispersibility of nano-CuO catalyst on heat releasing of propellants. With pre-dispersing procedures, thermal decomposition temperature of nano-CuO/AP and its propellant are about C and C lower than that of AP simple mixed with nano-CuO and its propellant, respectively. Comparing propellant with simple mixed nano-CuO kneading 3 hours, combustion heat and explosion heat of propellant with nano-CuO/AP increase about 1.4% and 1.7%, respectively. However, because of the breaking of nano-CuO/AP structure during kneading procedure, combustion heat and explosion heat of all the samples are decreased with the increase of kneading time after 3 hours.

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23

Filipovic, Milos, e Nikola Kilibarda. "The calculation of theoretical energetic performances of composite rocket propellants". Journal of the Serbian Chemical Society 66, n. 2 (2001): 107–17. http://dx.doi.org/10.2298/jsc0102107f.

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Abstract (sommario):

A suitable method for calculating theoretical energetic performances of a composite propellant was investigated and successfully verified. This method is based on generally accepted hypotheses, consistent and simple calculation of the chemical equilibrium in a predominantly gaseous, multi-component reactive mixture, and on an appropriate numerical scheme involving the propellant formula and the assigned rocket motor operating conditions. Acomputer program, which permits the calculation of the equilibrium composition of the combustion products and the theoretical energetic performances of composite propellants has been developed. The results of the calculations have been compared with data obtained by the programs OPHELIE, MICROPEP, and the program SPP, as documented in the NASA-Lewis Code, which is presently a world-wide standard. All comparisons gave satisfactory agreement.

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24

Dîrloman, F.-M., L.-C. Matache, T. Rotariu, T.-V. Țigănescu, D. Zvîncu, M.-I. Ungureanu e O. Iorga. "Computational fluid dynamics simulations for composite rocket propellant optimization". IOP Conference Series: Materials Science and Engineering 1182, n. 1 (1 ottobre 2021): 012017. http://dx.doi.org/10.1088/1757-899x/1182/1/012017.

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Abstract (sommario):

Abstract When designing a rocket engine configuration, both in terms of propellant grain, combustion chamber and nozzle geometry, one of the most convenient approach is using Computational Fluid Dynamics (CFD) Simulation. Numerical simulation is an alternative method of scientific investigation, which substitutes large number of experiments that often imply high financial burden and are also dangerous for the personnel involved. The numerical approach is often more useful than consecrated experimental method because it provides complete data that cannot be directly observed or measured, or it is difficult to highlight by other means. In this study we focused on applying CFD simulation to composite rocket propellants in a rocket engine with convergent-divergent nozzle configuration using Ansys Fluent Software. An ammonium nitrate (AN) based composite rocket propellant having four components was analyzed: oxidizer, metallic fuel, binder and catalyst agent. Explo5®, a thermochemical software, was also used to calculate the equilibrium compositions of the combustion products in the combustion chamber. It turned out that the results obtained on the basis of the simulation are consistent with those of the experimental testing. The data collected so far will be used to optimize the grain configuration of the composite rocket propellant.

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25

Pinalia, Anita, Bayu Prianto, Henny Setyaningsih, Prawita Dhewi e Ratnawati Ratnawati. "Design of Propellant Composite Thermodynamic Properties Using Rocket Propulsion Analysis (RPA) Software". Reaktor 22, n. 1 (12 luglio 2022): 1–6. http://dx.doi.org/10.14710/reaktor.22.1.1-6.

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Abstract (sommario):

Rocket Propulsion Analysis (RPA) is software for predicting the performance of a rocket engine. It is usually used in conceptual and preliminary design. Heat capacity and specific impulse are two properties related to the performance of a propellant. This work aimed to design AP/HTPB-based solid propellant composite with various compositions and predict the heat capacity and specific impulse using the RPA software. The materials used were ammonium perchlorate (AP) as the oxidizer, Hydroxy-Terminated Polybutadiene (HTPB) as the fuel binder, Al powder as the metal fuel, and other additives. Four propellants with different formulations were prepared and tested for heat capacity and specific impulse. The experimental heat capacity was obtained using a differential scanning calorimeter (DSC), while the specific impulse was obtained using a bomb calorimeter. The same propellant formulations were used as the input to the RPS to predict the heat capacity and specific impulse. The results show that the experimental heat capacity of the propellant ranges from 1.576 to 4.08 J g–1 K–1, and the simulation result ranges from 1.78 to 3.48 J g–1 K–1. The overall average deviation is 16.3%. The predicted specific impulse at vacuum and sea level ranges from 231.3 to 234.0 s and from 219.8 to 220.9 s, respectively. Meanwhile, the experimental specific impulse at vacuum and sea level varies from 236.2 to 240.3 s and from 228.5 to 232.9 s, respectively. The overall average deviation is 3.7%. Therefore, the RPA is reliable for predicting specific impulse of propellant, but it is not accurate enough for predicting the heat capacity of propellant composite.

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26

Li, Jun, Sheng Yu Bi e Gong Hui Liu. "Study on Combustion Model of the Propellant Used in Oil Composite Perforation". Advanced Materials Research 361-363 (ottobre 2011): 534–39. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.534.

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Abstract (sommario):

The new technology of composite perforation, which combines together the conventional perforation and the high energy gas fracturing, can effectively increase the hydrocarbon production and improve the enhancement of the oil/gas recovery. In recent years, the composite perforation technique has been widely used worldwide. However, this technology was not used extensively in Chinese oil filed because its research on the combustion characters of propellant is rare and the corresponding optimal perforation design is not practical. Based on a comprehensive analysis of the propellant’s burning features, we establish a new combustion model for the propellant used in composite perforation, which takes into account that the combustion consists of the cylinder layer burning and circular burning along the perforation tunnels. Using the actual well data from oilfield and the conventional parameters of domestic propellant, we use this new model to perform numerical simulations and analyze in detail the process of related pressure change. The simulation results are accordance with the actual data from field operation, which further confirms the reliability of the model. The established model can provide better references for the optimum design of composite perforation.

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27

Xia, Min, Qifa Yao, Huilian Yang, Tao Guo, Xiuxin Du, Yanjie Zhang, Guoping Li e Yunjun Luo. "Preparation of Bi2O3/Al Core-Shell Energetic Composite by Two-Step Ball Milling Method and Its Application in Solid Propellant". Materials 12, n. 11 (11 giugno 2019): 1879. http://dx.doi.org/10.3390/ma12111879.

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Abstract (sommario):

In this article, Bi2O3/Al high-density energetic composites with a core-shell structure were prepared by a two-step ball milling method using a common planetary ball milling instrument, and their morphology, structure, and properties were characterized in detail. Through a reasonable ratio design and optimization of the ball milling conditions, the density of the Bi2O3/Al core-shell energetic composite is increased by about 11.3% compared to that of the physical mixed sample under the same conditions. The DSC (Differential Scanning Calorimetry) test also showed that the exothermic quantity of the thermite reaction of the energetic composite reached 2112.21 J/g, which is very close to the theoretical exothermic quantity. The effect of Bi2O3/Al core-shell energetic composite on the energy performance of insensitive HTPE propellant was further studied. The theoretical calculation results showed that replacing the partial Al with Bi2O3/Al core-shell energetic composite can make the density of propellant reach 2.056 g/cm3, and the density specific impulse reach 502.3 s·g/cm3, which is significantly higher than the density and density specific impulse of the conventional composite solid propellant. The thermal test showed that the explosive heat of the HTPE (Hydroxyl terminated polyether) propellant also increased with the increase of the content of Bi2O3/Al core-shell energetic composite.

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28

Hoque, Ehtasimul, Chandra Shekhar Pant e Sushanta Das. "Statistical Evaluation of Burning Rate Data of Composite Propellants Obtained from Acoustic Emission Technique". Defence Science Journal 71, n. 1 (1 febbraio 2021): 18–24. http://dx.doi.org/10.14429/dsj.71.16007.

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Abstract (sommario):

The acoustic emission technique has been considered to be one of the most reliable and robust methods for the measurement of the steady burning rate of composite propellants. In this work, attempts were made to quantify the measurement variability of the burning rate of composite solid propellants by acoustic emission method using statistical tools. A total of 1100 individual measurements were subjected to statistical treatment. The combination of confidence interval and repeatability limit delineated the extent of natural dispersion in the burning rate measurement data. The very high coefficient of variation values for the propellant compositions, having a burning rate of more than 25 mm s–1 raised concerns about the suitability of the acoustic emission method for high burning rate compositions. The Reliability interval approach was employed to determine the statistically significant sample size for different composite propellants having a burning rate range of 5–31 mm s–1. The entire set of data was screened for identification of outlying observation using the Dixon Q test, and the extent of contamination was quantified. Moreover, the application of statistical techniques could have far-reaching implications for quality control perspectives of burning rate measurement by acoustic emission and could be implemented as reference tolerance limits and preventive measures for ensuring the good health of the instrument as well as propellant processing.

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Yang, Wei Jun, Jiu Ling Zhao e Suo Li Guo. "Mesh Generation for Ellipse Particles of Composite Solid Propellant". Advanced Materials Research 160-162 (novembre 2010): 1336–40. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.1336.

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Abstract (sommario):

For analyzing the effect of different particles composing and distributing on composite propellant, it is necessary to generate mesh for the elliptical particles in composite propellant. A mesh automatic generation method is designed for the elliptical particles. This method is according to force-equilibrium mesh generation algorithm. And distance function and mesh size function is designed for the method. The program is in Matlab. The result shows that the method can automatically generate mesh and the mesh quality is good.

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30

Liu, Ya Hao, Jian Zheng, Gui Bo Yu, Jing Qia, Quan Qun Xu, Chun Ming Zhang e Xiao Zhang. "Graphene-based Composites for the Thermal Decomposition of Energetic Materials". Materials Science Forum 1027 (aprile 2021): 123–29. http://dx.doi.org/10.4028/www.scientific.net/msf.1027.123.

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Abstract (sommario):

Owing to its remarkable mechanical, electrical and thermal properties, graphene has been a hot area of composites research in the past decade, including the field of energetic materials. Graphene has been widely applied in enhancing the physical properties of energetic materials, such as solid composite propellants. Through the way of adding different forms of graphene into the matrix of solid propellants, their thermal decomposition performance can be effectively improved. In this paper, we reviewed the status and challenges of the application of graphene in the thermal decomposition of composite solid propellant. Moreover, the main preparation methods and material structures of graphene are reviewed. We can conclude that graphene and its derivatives can enhance the catalytic effect remarkably, which can be attributed to the large specific surface area of graphene that makes the uniformly dispersed catalyst particles and the more catalyst active sites. Meanwhile, graphene possesses the high thermal conductivity, making the rapider heat diffusion, which can promote the decomposition reactions of the energetic components in solid propellants. Graphene and catalyst work synergistically in their thermal decomposition. More than this, the main methods to improve the thermal decomposition of energetic components of composite propellants and their effects on decomposition temperature reduction are systematically summarized, respectively.

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31

Liu, Yong, Luoxin Wang, Xinlin Tuo e Li Songnian. "An SEM and EDS study of the microstructure of nitrate ester plasticized polyether propellants". Journal of the Serbian Chemical Society 75, n. 3 (2010): 369–76. http://dx.doi.org/10.2298/jsc090326007l.

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Abstract (sommario):

To probe the microstructures of nitrate ester plasticized polyether (NEPE) composite propellants and observe the morphology of each constitute in the propellant, the microstructure and elemental constitutes of NEPE propellants were investigated using scanning electron microscopy and energy dispersive X-ray spectroscopy. The ammonium perchlorate (AP) grains had a scraggy surface and were difficult to disperse uniformly. The compatibility between the AP grains and the polymer binder was poor, especially for large grains. The size distribution range of the AP and octogen (HMX) grains in propellants varied from several to several hundreds ?m for the former while for the latter from several to several tens ?m. Contrasting images before and after dissolution the propellant in trichloromethane showed that the degree of crosslinking of the polymer binder was low since non-crosslinked binder on the surface areas was easily removed by the solvent, and that the plasticizer was near the HMX grains and contributed more O to the element analysis of HMX.

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32

Dong, Ge, Hengzhi Liu, Lei Deng, Haiyang Yu, Xing Zhou, Xianqiong Tang e Wei Li. "Study on the interfacial interaction between ammonium perchlorate and hydroxyl-terminated polybutadiene in solid propellants by molecular dynamics simulation". e-Polymers 22, n. 1 (1 gennaio 2022): 264–75. http://dx.doi.org/10.1515/epoly-2022-0016.

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Abstract (sommario):

Abstract The interfacial interaction between the main oxidant filler ammonium perchlorate (AP) and hydroxyl-terminated polybutadiene (HTPB) matrix in AP/HTPB propellants were studied via an all-atom molecular dynamics simulation. The results of the simulation showed the effects of the microscopic cross-linked structure of the matrix, stretching rate during uniaxial stretching, and contact area between the filler and matrix on the mechanical properties, such as the stress and strain of the composite solid propellant. Among the aforementioned factors, the stretching rate considerably affects the mechanical properties of the solid propellant, and the maximum stress of the solid propellant proportionally increases with the stretching rate. When defects were introduced on the surface of the AP filler, the contact area between the filler and matrix affected the strain type of the matrix molecules. Owing to the interaction between the molecules and atoms, the strain behaviour of the matrix molecule changed with the change in its microscopic cross-linked structure during uniaxial stretching. Molecular dynamics simulations were used to explore the characteristics at the AP–HTPB interface in AP/HTPB propellants. The aforementioned simulation results further revealed the interfacial interaction mechanism of the AP–HTPB matrix and provided a theoretical basis for the design of high-performance propellants.

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Xie, Zhi Min, Si Chi Chen e You Shan Wang. "Relaxation Properties of the Solid Propellant Based on Hydroxyl-Terminated Polybutadiene". Advanced Materials Research 989-994 (luglio 2014): 172–76. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.172.

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Abstract (sommario):

The polymer-based propellant is a typical viscoelastic material. Better understanding of the relaxation properties of the propellant in the storage conditions is of great importance for predicting the lifetime. Due to the component complexity of the composite propellants, the transformation relation between the relaxation modulus and the complex modulus may not be suitable for all kinds of propellants. In the present work, we focused on the transformation of the relaxation modulus and complex modulus for the HTPB propellant. The master curves for the relaxation modulus and the storage modulus of the aged/unaged HTPB propellants were obtained by performing the stress relaxation tests and DMA tests, respectively. It was found that there existed a great difference in the double logarithmic plot between relaxation modulus and storage modulus master curves. Moreover, the testing results for the relaxation modulus and the storage modulus were well fitted by an empirical transformation relation with three segment-related coefficients. These three coefficients were determined by using the unaged samples, and then were applied to estimate the relaxation modulus of the aged samples. A good agreement between the calculation and the experimental results was also found, revealing that the three coefficients were insensitive to the aging time.

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Li, Tianpeng, Jinsheng Xu, Junli Han e Yong He. "Effect of Microstructure on Micro-Mechanical Properties of Composite Solid Propellant". Micromachines 12, n. 11 (10 novembre 2021): 1378. http://dx.doi.org/10.3390/mi12111378.

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Abstract (sommario):

This study was aimed at determining the effect of microstructure on the macro-mechanical behavior of a composite solid propellant. The microstructure model of a composite solid propellant was generated using molecular dynamics algorithm. The correlation of how microstructural mechanical properties and the effect of initial interface defects in propellant act on the macro-mechanics were studied. Results of this study showed that the mechanical properties of propellant rely heavily on its mesoscopic structure. The grain filling volume fraction mainly influences the propellant initial modulus, the higher the volume fraction, the higher initial modulus. Additionally, it was found that the ratio of particles influences the tensile strength and breaking elongation rate of the propellant. The big particles could also improve the initial modulus of a propellant, but decrease its tensile strength and breaking elongation rate. Furthermore, the initial defects lowered the uniaxial tensile modulus, tensile strength, and the relaxation modulus of propellant, but did not affect the relaxation behavior of the propellant.

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35

Pang, Weiqiang, Yang Li, Luigi T. DeLuca, Daolun Liang, Zhao Qin, Xiaogang Liu, Huixiang Xu e Xuezhong Fan. "Effect of Metal Nanopowders on the Performance of Solid Rocket Propellants: A Review". Nanomaterials 11, n. 10 (17 ottobre 2021): 2749. http://dx.doi.org/10.3390/nano11102749.

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Abstract (sommario):

The effects of different types of nano-sized metal particles, such as aluminum (nAl), zirconium (nZr), titanium (nTi), and nickel (nNi), on the properties of a variety of solid rocket propellants (composite, fuel-rich, and composite modified double base (CMDB)) were analyzed and compared with those of propellants loaded with micro-sized Al (mAl) powder. Emphasis was placed on the investigation of burning rate, pressure exponent (n), and hazardous properties, which control whether a propellant can be adopted in solid rocket motors. It was found that nano-sized additives can affect the combustion behavior and increase the burning rate of propellants. Compared with the corresponding micro-sized ones, the nano-sized particles promote higher impact sensitivity and friction sensitivity. In this paper, 101 references are enclosed.

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36

Xie, Kan, Xiaoxu Chen, Yuejie Li, Long Bai, Ningfei Wang, Yiming Zhang e Haiyan Xiao. "Study of the Mechanical Properties of a CMDB Propellant Over a Wide Range of Strain Rates Using a Group Interaction Model". International Journal of Aerospace Engineering 2022 (14 maggio 2022): 1–15. http://dx.doi.org/10.1155/2022/7099199.

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Abstract (sommario):

Composite modified double base (CMDB) propellants are heterogeneous propellants in which properties are significantly improved by adding solid particles into the polymer matrix. A molecular group interaction model that can predict the mechanical properties of polymers through a molecular structure is used to predict the viscoelastic behavior of the CMDB propellant. Considering that the addition of solid particles will improve the crosslinking degree between polymer molecules and reduce its secondary loss peak, the input parameters of the model are modified through dynamic mechanical analysis (DMA) experimental data. By introducing the strain rate into the expression of model glass transition temperature, the mechanical properties of propellant over a wide strain range ( 1.7 × 10 − 4 s-1 ~ 3000 s-1) are obtained. The reliability of the model is verified by comparison with uniaxial compression test data. By modifying the input parameters of the model, the effects of different mass ratios of nitrocellulose (NC)/nitroglycerin (NG) on the mechanical properties of the CMDB propellant were analyzed. The results show that the glass transition loss increases with increasing mass ratio of NC/NG, while Young’s modulus and yield stress decrease.

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37

Zhao, Jiuling. "Meso-model Optimization of Composite Propellant Based on Hybrid Genetic Algorithm and Mass Spring System". Journal of Physics: Conference Series 2025, n. 1 (1 settembre 2021): 012036. http://dx.doi.org/10.1088/1742-6596/2025/1/012036.

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Abstract (sommario):

Abstract The meso-structure of composite propellant directly affects its macroscopic properties. The primary premise of studying the macroscopic characteristics of composite propellant is to establish the meso-structure model which can reflect the actual formulation characteristics.In order to obtain the optimal composite propellant meso-structure model suitable for numerical analysis and calculation, the hybrid genetic algorithm was used to optimize the reconstructed meso-structure model. In order to avoid different degree of overlap between particles, the mass spring system was further improved. The resulting meso-structure model not only preserves the statistical characteristics of the propellant, but also meets the requirement of minimizing the optimal size. The reconstruction and optimization algorithm of the optimal meso-structure model are established in this paper, which has high theoretical significance and engineering application value for the prediction of mechanical properties of composite propellant.

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Hoque, Ehtasimul, Chandra Shekhar Pant e Sushanta Das. "Study on Friction Sensitivity of Passive and Active Binder based Composite Solid Propellants and Correlation with Burning Rate". Defence Science Journal 70, n. 2 (9 marzo 2020): 159–65. http://dx.doi.org/10.14429/dsj.70.14802.

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Abstract (sommario):

Friction sensitivity of composite propellants and their ingredients is of significant interest to mitigate the risk associated with the accidental initiation while processing, handling, and transportation. In this work, attempts were made to examine the friction sensitivity of passive binder: Hydroxy Terminated Polybutadiene/Aluminium/Ammonium Perchlorate and active binder: (Polymer + Nitrate Esters)/Ammonium Perchlorate/Aluminium/Nitramine based composite propellants by using BAM Friction Apparatus. As per the recommendation of NATO standard STANAG–4487, the friction sensitivity was assessed by two methods: Limiting Frictional load and Frictional load for 50% probability of initiation (F50). The test results showed that the active binder based formulations were more vulnerable to frictional load as compared to the formulations with passive binders. Examination of a comprehensive set of propellant compositions revealed that the particle size distribution of Ammonium Perchlorate and burn rate catalysts were the most influential factors in dictating the friction sensitivity for HTPB/Al/AP composite propellants. For active binder/AP/Al/Nitramine composite propellants, the formulation with RDX was found more friction sensitive with a sensitivity value of 44 N as compared to its HMX analog (61 N). The correlation studies of friction sensitivity, burning rate, and thermal decomposition characteristics of HTPB/Al/AP composite propellants is described.

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39

Khan, M. B. "Simulation of Composite Propellant Aging". Polymer-Plastics Technology and Engineering 32, n. 5 (settembre 1993): 467–89. http://dx.doi.org/10.1080/03602559308021016.

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Korotkikh, Alexander, Ivan Sorokin e Ekaterina Selikhova. "Ignition and combustion of high-energy materials containing aluminum, boron and aluminum diboride". MATEC Web of Conferences 194 (2018): 01055. http://dx.doi.org/10.1051/matecconf/201819401055.

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Abstract (sommario):

Boron and its compounds are among the most promising metal fuel components to be used in solid propellants for solid fuel rocket engine and ramjet engine. Papers studying boron oxidation mostly focus on two areas: oxidation of single particles and powders of boron, as well as boron-containing composite solid propellants. This paper presents the results of an experimental study of the ignition and combustion of the high-energy material samples based on ammonium perchlorate, ammonium nitrate, and an energetic combustible binder. Powders of aluminum, amorphous boron and aluminum diboride, obtained by the SHS method, were used as the metallic fuels. It was found that the use of aluminum diboride in the solid propellant composition makes it possible to reduce the ignition delay time by 1.7–2.2 times and significantly increase the burning rate of the sample (by 4.8 times) as compared to the solid propellant containing aluminum powder. The use of amorphous boron in the solid propellant composition leads to a decrease in the ignition delay time of the sample by a factor of 2.2–2.8 due to high chemical activity and a difference in the oxidation mechanism of boron particles. The burning rate of this sample does not increase significantly.

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Zhao, J. L., e H. F. Qiang. "Numerical Scheme for Micro-Damage Mechanism of Composite Propellant". Key Engineering Materials 417-418 (ottobre 2009): 265–68. http://dx.doi.org/10.4028/www.scientific.net/kem.417-418.265.

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Abstract (sommario):

HTPB propellant is the high filled particulate elastomeric matrix composite. Debonding of particle/matrix interfaces can significantly affect the macroscopic behavior of composite propellant. How to model the propellant material and describe damage processes to discover damage mechanism has been a long-standing question. This paper used the bilinear cohesive law with different parameter values for particle/matrix interfaces to study interface debonding. By analyzing the damage evolution in two model particulate composite systems with finite element method, the scheme was shown to capture effects associated with the interface strength and the interactions between particles.

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Aritonang, Sovian, Maykel Manawan, Mas Ayu Elita Hafizah, Timbul Siahaan, Shofi S. Muktiana, Hanung Bayu Setiawan, Sih Wuri Andayani et al. "Crystal Characterization of Anionic Salt Compounds as Composite of Solid Propellant Oxidizing Agent". Materials Science Forum 1028 (aprile 2021): 269–75. http://dx.doi.org/10.4028/www.scientific.net/msf.1028.269.

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Abstract (sommario):

Composite solid propellants are preferred for use in defense and space applications because of their high energy density and simplicity. Oxidizers take up the highest percentage in propellant ingredient. KNO3, KClO4 and K2Cr2O7 are among the inorganic oxidizers with similar cation for present study, and their chemical and physical properties are fully understood. However, the relationship between thermal stability and electrostatic potential energy based on structural analysis has not yet been studied. In this study we used high resolution XRD data to study the electrostatic potential energy of the KNO3, KClO4 and K2Cr2O7 crystal structures.

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Jabez, I. Kingstone Lesley, Urmila Das, R. Manivannan e Sarat Babu Anne. "Influence of HTPB prepolymer on achieved properties of composite solid propellant". High Performance Polymers 31, n. 9-10 (26 febbraio 2019): 1162–72. http://dx.doi.org/10.1177/0954008319830468.

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Abstract (sommario):

Changes/variations during manufacturing and storage of free radical-polymerized hydroxyl-terminated polybutadiene resin/prepolymer (widely used binder for the composite solid propellants) are not reflected in terms of appreciable change in the hydroxyl value. As a result, cured properties of the propellant mixed using the given formulation finalized by keeping R ratio (NCO/OH ratio) within 0.7–0.9 did not yield predicted mechanical properties. Investigations carried out subsequently, by the authors, identified the root cause to be variations in molecular weight and its distribution, which were not indicated in terms of change in hydroxyl value. Authors confirmed their findings by 1H1NMR studies whereby the variation in molecular weight distribution could be explained in terms of variation in spin–spin relaxation time ( T 2) values.

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Madi, V. V. "Mathematical simulation of rocket engine with a composite sectional charge". Journal of «Almaz – Antey» Air and Space Defence Corporation, n. 3 (30 settembre 2016): 36–40. http://dx.doi.org/10.38013/2542-0542-2016-3-36-40.

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Abstract (sommario):

Due to the need to improve the appearance of the solid-propellant rocket engine, we stated the task of developing the methods allowing us to calculate internal ballistics performance of a composite sectional charge of solid propellant. These methods were implemented on a computer in the mathematical package MathCAD Prime 3.0, it has accuracy that is sufficient for technical evaluation of the rocket engine using solid propellant with the sectional charge.

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Li, Hui, Qi-xuan Song, Xuan Wu, Jin-sheng Xu e Xiong Chen. "Research on the statistical damage constitutive model for composite solid propellant". Journal of Physics: Conference Series 2235, n. 1 (1 maggio 2022): 012059. http://dx.doi.org/10.1088/1742-6596/2235/1/012059.

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Abstract (sommario):

Abstract The study of constitutive model of composite solid propellant is an important basis for analyzing the structural integrity of propellant grains of the solid rocket motor. From the view of microscopic, composite solid propellant is composed of a large number of solid particles with various sizes embedded in the matrix. In this paper, based on the distribution of solid particles with different sizes and the failure strength of the particle-matrix interfaces, the damage evolution was assumed to obey the Weibull distribution function and power law distribution function, and the two statistical damage constitutive models were first established. Then, the model parameters were identified and validated through the uniaxial tensile tests data of HTPB propellant. Finally, the prediction abilities of the developed two models were compared. The results show that both of the two statistical damage models can describe the stress-strain curves of HTPB propellant well.

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Huang, Liuchun, Jian Li e Bojun Li. "Experimental research on ultrasonic A-scan testing technology of composite solid propellant". Journal of Physics: Conference Series 2338, n. 1 (1 settembre 2022): 012011. http://dx.doi.org/10.1088/1742-6596/2338/1/012011.

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Abstract (sommario):

Abstract To explore the application and development of ultrasonic non-destructive testing technology in composite solid propellant materials, the theory is combined with the principle and method of ultrasonic non-destructive testing technology and the material characteristics of composite solid propellant; Based on ultrasonic A-scan, the experimental testing of propellant grain with multiphase structure, complex properties and high attenuation was carried out using pulse reflection method and penetration method. For the testing system with probe emission frequency of 1 MHz and gain adjustable range of 60 dB, the thickness of propellant grain is recommended to be 10 ~ 50 mm for the pulse reflection method to effectively observe the first bottom echo and the second bottom echo, and the thickness of propellant grain is recommended to be less than or equal to 100 mm for the penetration method to effectively observe the transmission waveform. The coupling modes of ultrasonic testing technology are further analyzed, and the effect test is carried out. In addition, based on the pulse reflection method of direct contact coupling, the sound velocity of propellant grain is measured with probes with different frequencies. The results show that the higher the probe frequency is, the smaller the sound velocity of propellant grain is.

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KAKADE, S. D., S. B. NAVALE e V. L. NARSIMHAN. "Studies on Interface Properties of Propellant Liner for Case-Bonded Composite Propellants". Journal of Energetic Materials 21, n. 2 (aprile 2003): 73–85. http://dx.doi.org/10.1080/713845500.

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Aziz, Amir, Rizalman Mamat, Makeen Amin e Wan Khairuddin Wan Ali. "Effect of Propellant Composition to the Temperature Sensitivity of Composite Propellant". IOP Conference Series: Materials Science and Engineering 36 (18 settembre 2012): 012023. http://dx.doi.org/10.1088/1757-899x/36/1/012023.

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Miccio, F. "Numerical modeling of composite propellant combustion". Symposium (International) on Combustion 27, n. 2 (gennaio 1998): 2387–95. http://dx.doi.org/10.1016/s0082-0784(98)80090-8.

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Hegab, A. M., e S. A. Gutub. "An Overview of Composite Propellant Burning". International Journal of Engineering Trends and Technology 27, n. 2 (25 settembre 2015): 118–23. http://dx.doi.org/10.14445/22315381/ijett-v27p220.

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