M. Keshavarz, Seyyed Mohammad Hossein Hosseini, M. Karimi
This work introduces dynamic mechanical thermal analysis (DMTA) as an efficient method for the assessment of the shelf life of solid composite solid propellants in air and nitrogen atmospheres. The samples were aged at three temperatures 323.15, 333.15, and 343.15 K for 60, 120, and 180 days. The two different methods of Arrhenius and Berthelot were used to compare the effects of air and nitrogen atmospheres on the ageing of composite solid propellants. Damping (Tan δ) of composite solid propellants was used to determine the shelf life of the samples based on the loss of half of the physical property Tan δ (50% drop in damping). For the air atmosphere, the calculated activation energy for the degradation reactions of the samples was 86.26 kJ·mol–1. Both models, Arrhenius and Berthelot, confirmed that the shelf lives of the samples under the nitrogen atmosphere are more than four times those in an air atmosphere.
{"title":"Assessment of the Shelf Life of Composite Solid Propellants in Air and Nitrogen Atmospheres through Thermal Ageing","authors":"M. Keshavarz, Seyyed Mohammad Hossein Hosseini, M. Karimi","doi":"10.22211/CEJEM/134663","DOIUrl":"https://doi.org/10.22211/CEJEM/134663","url":null,"abstract":"This work introduces dynamic mechanical thermal analysis (DMTA) as an efficient method for the assessment of the shelf life of solid composite solid propellants in air and nitrogen atmospheres. The samples were aged at three temperatures 323.15, 333.15, and 343.15 K for 60, 120, and 180 days. The two different methods of Arrhenius and Berthelot were used to compare the effects of air and nitrogen atmospheres on the ageing of composite solid propellants. Damping (Tan δ) of composite solid propellants was used to determine the shelf life of the samples based on the loss of half of the physical property Tan δ (50% drop in damping). For the air atmosphere, the calculated activation energy for the degradation reactions of the samples was 86.26 kJ·mol–1. Both models, Arrhenius and Berthelot, confirmed that the shelf lives of the samples under the nitrogen atmosphere are more than four times those in an air atmosphere.","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":"18 1","pages":"25-45"},"PeriodicalIF":0.8,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47534287","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ke Wang, Hai-tao Huang, Huixiang Xu, Huan Li, Jun-qiang Li, X. Fan, W. Pang
Based on Energy Calculation Star program and molecular dynamic method, three designed 2,3-bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol tetranitrate-based (BHDBT) propellants are firstly reported and their physicochemical performance are investigated. Results suggest that compared with HMX-based and CL-20-based propellants, the specific impulses of all BHDBT-based propellants surpass or approximate 280 s, which indicates the latter have the potential to be high-energy propellants. The diffusion coefficient of plasticizers in BHDBT-based propellant decrease as the temperature reduces, and reduce in the order: Bu-NENA > TMETN > BTTN. The densities of all BHDBT-based propellants surpass or approximate 1.7 g/cm3. The comparison of elastic constants, Poisson’s ratios and K/G values indicates that the mechanical properties of three BHDBT-based propellants increase in the order (by plasticizer): Bu-NENA < TMETN < BTTN. The bond length analysis of C–NO2 and O–NO2 bond in BHDBT suggests that the former is the trigger bond in the BHDBT-based propellants, and the safety of BHDBT-based propellants and BHDBT crystal decreases in the order: GAP/BTTN/Al/BHDBT > GAP/Bu-NENA/Al/BHDBT ≈ GAP/TMETN/Al/BHDBT > BHDBT. In conclusion, GAP/BTTN/Al/BHDBT propellant has the potential to be a novel high-energy propellant.
{"title":"Theoretical Simulations on Physicochemical Performance of Novel High-energy BHDBT-based Propellants","authors":"Ke Wang, Hai-tao Huang, Huixiang Xu, Huan Li, Jun-qiang Li, X. Fan, W. Pang","doi":"10.22211/CEJEM/134652","DOIUrl":"https://doi.org/10.22211/CEJEM/134652","url":null,"abstract":"Based on Energy Calculation Star program and molecular dynamic method, three designed 2,3-bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol tetranitrate-based (BHDBT) propellants are firstly reported and their physicochemical performance are investigated. Results suggest that compared with HMX-based and CL-20-based propellants, the specific impulses of all BHDBT-based propellants surpass or approximate 280 s, which indicates the latter have the potential to be high-energy propellants. The diffusion coefficient of plasticizers in BHDBT-based propellant decrease as the temperature reduces, and reduce in the order: Bu-NENA > TMETN > BTTN. The densities of all BHDBT-based propellants surpass or approximate 1.7 g/cm3. The comparison of elastic constants, Poisson’s ratios and K/G values indicates that the mechanical properties of three BHDBT-based propellants increase in the order (by plasticizer): Bu-NENA < TMETN < BTTN. The bond length analysis of C–NO2 and O–NO2 bond in BHDBT suggests that the former is the trigger bond in the BHDBT-based propellants, and the safety of BHDBT-based propellants and BHDBT crystal decreases in the order: GAP/BTTN/Al/BHDBT > GAP/Bu-NENA/Al/BHDBT ≈ GAP/TMETN/Al/BHDBT > BHDBT. In conclusion, GAP/BTTN/Al/BHDBT propellant has the potential to be a novel high-energy propellant.","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":"18 1","pages":"5-24"},"PeriodicalIF":0.8,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45604702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article considers aspects of the flow, rheology, and viscometry of guncotton pulp. It is substantiated that during production guncotton pulp is subjected to shear deformation, taking into account sliding over smooth surfaces, in the input zones of the dies, in the barrel, and on the crimped finned tube of the screw extruder. At the same time, the presence of shear stress in guncotton pulp has not been established. A rotational viscometer with a torque meter, which was developed during this research, enabled the presence of shear stress in guncotton pulp to be demonstrated. The values of the flow stress depend on the solvent content in the guncotton pulp; as this is decreased, the τ0 value increases. When the flow curve for the section from τ0 to τRmax was constructed, the flow curves of the guncotton pulp were described by the Herschel-Bulkley equation. The flow curves of guncotton pulp obtained on corrugated capillaries of different sizes are non-invariant and depend on the magnitude of the deformation of the guncotton pulp in the capillaries. Guncotton pulp flows in a narrow range of pressures and deformations.
{"title":"Shear Flow of Guncotton Pulp","authors":"V. Banishevsky, R. Zakusylo, D. Zakusylo","doi":"10.22211/CEJEM/134904","DOIUrl":"https://doi.org/10.22211/CEJEM/134904","url":null,"abstract":"This article considers aspects of the flow, rheology, and viscometry of guncotton pulp. It is substantiated that during production guncotton pulp is subjected to shear deformation, taking into account sliding over smooth surfaces, in the input zones of the dies, in the barrel, and on the crimped finned tube of the screw extruder. At the same time, the presence of shear stress in guncotton pulp has not been established. A rotational viscometer with a torque meter, which was developed during this research, enabled the presence of shear stress in guncotton pulp to be demonstrated. The values of the flow stress depend on the solvent content in the guncotton pulp; as this is decreased, the τ0 value increases. When the flow curve for the section from τ0 to τRmax was constructed, the flow curves of the guncotton pulp were described by the Herschel-Bulkley equation. The flow curves of guncotton pulp obtained on corrugated capillaries of different sizes are non-invariant and depend on the magnitude of the deformation of the guncotton pulp in the capillaries. Guncotton pulp flows in a narrow range of pressures and deformations.","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":"18 1","pages":"124-142"},"PeriodicalIF":0.8,"publicationDate":"2021-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49537177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The Shooting Tests of Target Perforating Ability, Performed on Cast Concrete Cylinders","authors":"Ł. Habera, Kamil Hebda, P. Koślik, T. Sałaciński","doi":"10.22211/cejem/132066","DOIUrl":"https://doi.org/10.22211/cejem/132066","url":null,"abstract":"","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47535557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. D. B. Yamajala, Hema Singh, Ramesh Kurva, M. Maurya, Shaibal Banerjee
{"title":"Composite Propellant Formulation of Poly (16-, 32- and 64-) Azido Dendritic Esters as Energetic Plasticizer and Evaluation of Properties","authors":"K. D. B. Yamajala, Hema Singh, Ramesh Kurva, M. Maurya, Shaibal Banerjee","doi":"10.22211/cejem/131235","DOIUrl":"https://doi.org/10.22211/cejem/131235","url":null,"abstract":"","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":"17 1","pages":"506-522"},"PeriodicalIF":0.8,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42945413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Detonation calorimetry is a method for the determination of the heat released by the detonation of an explosive charge. Compared to classical combustion calorimetry, detonation calorimetry requires an inert atmosphere, a large sample mass and a detonator for its initiation. This detonator releases some energy for which the results must be corrected. Four types of detonator have been tested in the calorimeter alone and also in combination with explosive charges of PETN. It was found that the aluminium shell of the detonator considerably increases the apparent heat of detonation of the PETN samples in a vacuum, while the presence of combustible (polymeric) components has the opposite effect. Pressurization of the calorimetric vessel with nitrogen gas only partially suppresses these effects. The preferred technique is to use copper or glass confinement in a high pressure inert atmosphere.
{"title":"The Effect of Detonator Shell Materials on Detonation Calorimetry Results","authors":"O. Němec, Tomáš Musil, M. Künzel","doi":"10.22211/cejem/131804","DOIUrl":"https://doi.org/10.22211/cejem/131804","url":null,"abstract":"Detonation calorimetry is a method for the determination of the heat released by the detonation of an explosive charge. Compared to classical combustion calorimetry, detonation calorimetry requires an inert atmosphere, a large sample mass and a detonator for its initiation. This detonator releases some energy for which the results must be corrected. Four types of detonator have been tested in the calorimeter alone and also in combination with explosive charges of PETN. It was found that the aluminium shell of the detonator considerably increases the apparent heat of detonation of the PETN samples in a vacuum, while the presence of combustible (polymeric) components has the opposite effect. Pressurization of the calorimetric vessel with nitrogen gas only partially suppresses these effects. The preferred technique is to use copper or glass confinement in a high pressure inert atmosphere.","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48014371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nitramines of high quality for manufacturing high-energy composites, such as oсtogen (HMX) and hexogen, have received much attention by researchers worldwide. Mixed formulations containing fillers in the form of spheroidal dispersed particles of explosives are homogenized at lower energy consumption. They are characterized by stable rheological characteristics, which guarantee the quality of the products obtained on the basis thereof. Methods for obtaining spherical nitramine particles by means of ultrasonic and hydromechanical rounding using commercial HMX were evaluated. It was found that under similar conditions, rounding by the hydromechanical process in a vortex device is more efficient and less energy-consuming than that of the ultrasonic method. It was confirmed that spheroidization of commercial HMX in an aqueous dimethyl sulfoxide (DMSO) medium by hydromechanical rounding occurs due to erosion of crystals of large size (70 μm or more). Based on the experimental results with spheroidization of commercial nitramine, the mass fraction content below 50 μm versus time was plotted for hydromechanical rounding. The method of hydromechanical rounding in aqueous DMSO to obtain spheroidized HMX, extracted from solid propellant using DMSO, was found to be the most suitable. Spheroidized modified HMX with specific characteristics (density and crystals of near-spherical shape) was obtained, which could be used for the manufacture of high-energy composites.
{"title":"Regularities of Spheroidization of HMX Extracted from Solid Propellant Disposal Products","authors":"Maksym Cheltonov, R. Zakusylo, I. Ustymenko","doi":"10.22211/cejem/131782","DOIUrl":"https://doi.org/10.22211/cejem/131782","url":null,"abstract":"Nitramines of high quality for manufacturing high-energy composites, such as oсtogen (HMX) and hexogen, have received much attention by researchers worldwide. Mixed formulations containing fillers in the form of spheroidal dispersed particles of explosives are homogenized at lower energy consumption. They are characterized by stable rheological characteristics, which guarantee the quality of the products obtained on the basis thereof. Methods for obtaining spherical nitramine particles by means of ultrasonic and hydromechanical rounding using commercial HMX were evaluated. It was found that under similar conditions, rounding by the hydromechanical process in a vortex device is more efficient and less energy-consuming than that of the ultrasonic method. It was confirmed that spheroidization of commercial HMX in an aqueous dimethyl sulfoxide (DMSO) medium by hydromechanical rounding occurs due to erosion of crystals of large size (70 μm or more). Based on the experimental results with spheroidization of commercial nitramine, the mass fraction content below 50 μm versus time was plotted for hydromechanical rounding. The method of hydromechanical rounding in aqueous DMSO to obtain spheroidized HMX, extracted from solid propellant using DMSO, was found to be the most suitable. Spheroidized modified HMX with specific characteristics (density and crystals of near-spherical shape) was obtained, which could be used for the manufacture of high-energy composites.","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47932506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Chmielarek, Paweł Maksimowski, Katarzyna Cieślak, T. Gołofit, Hanna Drozd
{"title":"Study of the Synthesis of GAP-HTPB-GAP Liquid Copolymer","authors":"M. Chmielarek, Paweł Maksimowski, Katarzyna Cieślak, T. Gołofit, Hanna Drozd","doi":"10.22211/cejem/131803","DOIUrl":"https://doi.org/10.22211/cejem/131803","url":null,"abstract":"","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47069364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Estimation of the Detonation Pressure of Co-crystal Explosives through a Novel, Simple and Reliable Model","authors":"N. Zohari, M. Montazeri, S. G. Hosseini","doi":"10.22211/cejem/131687","DOIUrl":"https://doi.org/10.22211/cejem/131687","url":null,"abstract":"","PeriodicalId":9679,"journal":{"name":"Central European Journal of Energetic Materials","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2020-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44715299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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