检索结果-内蒙古大学图书馆

deflagration-to-detonation transition in Nitrous Oxide/Oxygen-Fuel Mixtures for Propulsion

JOURNAL OF PROPULSION AND POWER 2019年第5期35卷 944-952页

作者： Venkatesh, Prashanth Bangalore Meyer, Scott E. Bane, Sally P. M. Grubelich, Mark C. Purdue Univ Sch Aeronaut & Astronaut W Lafayette IN 47907 USA Purdue Univ Maurice J Zucrow Labs W Lafayette IN 47907 USA Sandia Natl Labs POB 5800 Albuquerque NM 87185 USA

Nitrous oxide (N2O) has gained popularity as a unique oxidizer for propulsion applications due to its ability to decompose exothermically, producing nitrogen and oxygen. In the current work, the flame acceleration, deflagration-to-detonation transition, and detonation properties of bipropellant mixtures with N2O as the oxidizer are studied for potential applications in pulsed blowdown and detonation-driven thrusters. These properties are compared with those in mixtures with oxygen (O2) or nitrogen tetroxide (N2O4) as the oxidizer. The performance of N2O versus O2/N2O4 for detonation engine applications is investigated using theoretical Chapman-Jouguet detonation calculations of bipropellant systems with ethylene (C2H4) and acetylene (C2H2) as fuels. A critical requirement for the application of bipropellant mixtures to pulsed propulsion systems is rapid flame acceleration to achieve significant chamber pressure rise in a short distance with the potential for a prompt transition to detonation. This deflagration-to-detonation transition behavior of mixtures using C2H4 and C2H2 with N2O and O2 is investigated for increasing initial pressures in the experimental portion of this work. While C2H2 is a highly energetic fuel with theoretically high performance, it presents serious practical storage concerns when considered for propulsion applications. These practical issues motivate investigation of C2H4 as a potential alternative fuel, which is relatively easy to manage. The precompression of the bipropellant mixtures during flame acceleration is also estimated and compared.

关键词： Propulsion System Alternative Fuels deflagration to detonation transition Bipropellants Chamber Pressure Pressure Transducers Mass Flow Rate Vapour Pressure Monopropellants Relief Valves

来源：评论

学校读者我要写书评

暂无评论

deflagration-to-detonation transition in nitrous oxide-ethylene mixtures and its application to pulsed propulsion systems 55

Deflagration-to-detonation transition in nitrous oxide-ethyl...

引用

55th AIAA Aerospace Sciences Meeting

作者： Venkatesh, Prashanth Bangalore Graziano, Tyler J. Bane, Sally P. M. Meyer, Scott E. Grubelich, Mark C. Purdue University School of Aeronautics & Astronautics 701 W. Stadium Rd West LafayetteIN47907 United States Purdue University Zucrow Laboratories 500 Allison Rd West LafayetteIN47907 United States Sandia National Laboratories P.O. Box 5800 AlbuquerqueNM87185 United States

ISBN: (数字)9781624104473

ISBN: (纸本)9781624104473

In the past several years nitrous oxide has been more widely considered as a “safe”, clean oxidizer for rocket propulsion systems, that was useable as both a monopropellant or as a bipropellant. Therefore, the present work investigated the use of nitrous oxide and ethylene as a bi-propellant mixture at elevated pressures. Earlier work with this bipropellant mixture suggested that a steady detonation can be established in a combustion tube of larger L/d ratio and the associated flame acceleration prior to DDT could be studied more accurately. In order to use this bi-propellant mixture in a pulsed detonation engine quick flame acceleration is essential and this leads to a transition to detonation in a short duration of time. To study the flame acceleration and DDT behavior, tests were carried out in a combustion tube with L/d = 68 and detonation pressures were recorded using high pressure (100,000 psia) transducers. The detonation velocities were determined based on the time instances of measured pressure peaks and the distances between the transducers. Additionally, the pre compression observed in the combustible mixture before transitioning to a detonation was also studied and described in this paper. Finally, the run-up distances from these tests were determined and compared with values for different fuel-oxidizer mixtures from literature. © 2017 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

关键词： deflagration to detonation transition Propulsion System Bipropellants Pressure Transducers Pulse detonation Engine Rocket Propulsion System Monopropellants Critical Temperature detonation Waves Airborne Launch Assist Space Access

来源：评论

学校读者我要写书评

暂无评论

Smoked Foil on deflagration-to-detonation transition

引用

JOURNAL OF PROPULSION AND POWER 2015年第3期31卷 968-969页

作者： Wen, C. S. Chung, K. M. Hsu, Y. C. Lu, F. K. Natl Cheng Kung Univ Automot Res & Testing Ctr Tainan 711 Taiwan Natl Cheng Kung Univ Tainan 711 Taiwan Univ Texas Arlington Arlington TX 76019 USA

Single-shot experiments for propane/oxygen mixtures under atmospheric conditions were conducted to investigate the effect of the thickness and the axial location of an aluminum sheet on the deflagration-to-detonation transition (DDT). The smooth tube was constructed from 6061-T6 aluminum, with a length of 1143 mm and an inner tube diameter of 101.6 mm. The ignition system consisted of a transformer and an electric spark at the closed end. The duration and energy of the electrical discharge were estimated to be 2 ms and 0.47 J, respectively. The proportions of propane and oxygen were determined using the method of partial pressures with an equivalence ratio ranging from 0.6 to 1.0. Single-shot experiments were performed with initial reactant conditions at ambient temperature and atmospheric pressure. The study shows that caution must be exercised in using smoked foil results for developing pulse detonation engine (PDEs). The smoked foil should be placed well downstream of the end of transition. In particular, the crucial issue of DDT for practical sizing of a PDE should be carefully assessed. detonation cell size is commonly used to guide in sizing the diameter of a PDE.

关键词： deflagration to detonation transition Pressure Transducers detonation Waves Pulse detonation Engine Photodiodes Data Acquisition Kerosene Thermodynamic Efficiency Atmospheric Conditions Propulsion System

来源：评论

学校读者我要写书评

暂无评论

Study on the Mechanism of the deflagration to detonation transition Process of Explosive

引用

JOURNAL OF ENERGETIC MATERIALS 2014年第4期32卷 238-251页

作者： Wei, Lan Dong, Hefei Pan, Hao Hu, Xiaomian Zhu, Jianshi Inst Appl Phys & Computat Math Beijing 10094 Peoples R China Natl Key Lab Computat Phys Beijing Peoples R China

We present a numerical study of the mechanisms of the deflagration to detonation transition (DDT) process of explosives to assess its thermal stability. We treated the modeling system as a mixture of solid explosives and gaseous reaction products. We utilized a one-dimensional two-phase flow modeling approach with a space-time conservation element and solution element (CE/SE) method. Simulation results show that in the chemical reaction process a plug area of high density with relatively slow chemical reactions preceeds the new violent reactions and the consequent detonation. We found that steady detonation occurs at the regions where physical characteristics, such as pressure, density, temperature, and velocity, peak simultaneously. These simulation results agree well with high-temperature DDT tube experiments.

关键词： CE SE method deflagration to detonation transition explosive two phase flow

来源：评论

学校读者我要写书评

暂无评论

Effect of Temperature, Density and Confinement on deflagration to detonation transition of an HMX-Based Explosive

引用

PROPELLANTS EXPLOSIVES PYROTECHNICS 2014年第4期39卷 563-567页

作者： Dai, Xiao-Gan Wen, Yu-Shi Huang, Feng-Lei Huang, Hui Huang, Yi-Min Beijing Inst Technol Beijing 100081 Peoples R China China Acad Engn Phys Inst Chem Mat Mianyang 621900 Sichuan Peoples R China China Acad Engn Phys Mianyang 621900 Sichuan Peoples R China

In order to obtain the characteristics of the deflagration-to-detonation transition (DDT) of PBX-2 (an HMX-based explosive) under different conditions, DDT tests were carried out as a function of charge density, temperature, and shell confinement. In these tests, the energetic materials were electrically ignited. The DDT response characteristics for PBX-2 with 53% and 99% of theoretical maximum density (TMD) were evaluated by different shell thickness confinements at ambient temperature and at 85 degrees C. The test results with different densities, confinements and temperatures exhibited a wide range of reaction violence. Firstly, at both ambient temperature and at 85 degrees C under 10 and 20 mm shell thickness confinement, PBX-2 did not undergo fully DDT at 99% TMD, only a low velocity detonation (LVD) occurred. Secondly, PBX-2 at 53% TMD underwent DDT, and significant influence on the minimum run distance to detonation by the shell confinement thickness was observed. Strong confinement is favorable for the transition of DDT but the confinement does not influence reaction degree. Thirdly, the reaction degree of PBX-2 at 85 degrees C was remarkably lower than that at ambient temperature. This insensitizing effect of temperature is induced by the melting and flowing of bonders which reduces the porosity and inhibits an important step of DDT, namely, high turbulent combustion.

关键词： Explosion mechanisms Explosive safety deflagration to detonation transition HMX-based explosives

来源：评论

学校读者我要写书评

暂无评论

deflagration to detonation transition and detonation structure in diethyl ether mist/aluminum dust/air mixtures

引用

FUEL 2013年 107卷 400-408页

作者： Bai, Chunhua Zhang, Bo Xiu, Guangli Liu, Qingming Chen, Mo Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China E China Univ Sci & Technol Sch Resources & Environm Engn Shanghai 200237 Peoples R China CNPC Res Inst Safety & Environm Technol Beijing 100083 Peoples R China

Although diethyl ether (DEE) is an excellent compression-ignition fuel, it is extremely flammable and presents a serious fire and explosion hazard. Therefore, before widespread use of DEE as an energy carrier, its safety-related issues must first be addressed. In this study, experiments of transition from deflagration to detonation (DDT) and detonation structure in DEE mist/air and DEE mist/aluminum dust/air mixtures are carried out in a horizontal tube of inner diameter 19.9 cm and length 32.4 m. The mixtures are initiated by a high-voltage electric spark and the histories of pressure wave are recorded by 17 Kistler pressure transducers in the axial direction along the tube to study the DDT process. To study the detonation structure, 4 cross-sections are chosen during the self-sustained propagation phase of the detonation where, 8 pressure transducers are arranged with the same interval angle of 45 degrees on the same tube circumference to obtain the pressure profiles. The experimental results indicate that, deflagration cannot successfully transmit to detonation in DEE mist/air mixtures when DEE concentrations are 164 and 229 g/m(3). deflagration is observed to continuous accelerate and the onset detonation occurs at distance of 17.15 m as DEE concentration is increased up to 295 g/m(3), in which a double-headed spinning detonation structure is observed. Among the 5 different mixture composition of DEE mist/aluminum dust/air, DDT phenomenon is only observed in the mixtures of DEE mist (367 g/m(3))/aluminum dust (184 g/m(3))/air and DEE mist (314 g/m(3))/aluminum dust (230 g/m(3))/air, the run-up distances of DDT are 19.25 and 15.05 m, respectively. A single-headed spinning detonation structure is observed in DEE mist (314 g/m(3))/aluminum dust (230 g/m(3))/air mixture. (c) 2013 Elsevier Ltd. All rights reserved.

关键词： deflagration to detonation transition detonation structure Diethyl ether Aluminum dust

来源：评论

学校读者我要写书评

暂无评论

Parametric transition from deflagration to detonation revisited: Planar geometry

引用

COMBUSTION AND FLAME 2020年 211卷 465-476页

作者： Gordon, Peter V. Kagan, Leonid Sivashinsky, Gregory Kent State Univ Dept Math Sci Kent OH 44242 USA Tel Aviv Univ Sch Math Sci Sackler Fac Exact Sci IL-69978 Tel Aviv Israel

The paper is concerned with identification of the key mechanisms controlling deflagration-to-detonation transition in confined and unconfined gaseous systems. The issue of thermal runaway triggered by positive feedback between the advancing flame and the flame-driven precursor shock is revisited. A new mechanism for parametric transition based on the flame-speed sensitivity to pressure changes is discussed. Depending on the parameters of the system the transition may occur either within the subsonic, sonic or supersonic range of deflagrations. In the latter case the deflagration obeys the classical Chapman-Jouguet (CJ) condition. In a certain parameter range the adopted model reproduces the experimentally known situation where the transition occurs close to the sonic point. (C) 2019 The Combustion Institute. Published by Elsevier Inc. All rights reserved.

关键词： Parametric transition deflagration to detonation transition Planar geometry

来源：评论

学校读者我要写书评

暂无评论

The Research on Explosive's deflagration to detonation transition by Using Ignition Growth Model

The Research on Explosive's Deflagration to Detonation Trans...

引用

the 5th International Conference on Mechanical Engineering and Mechanics

作者： Bo ZHANG Tao ZHOU Teng ZHENG Xi'an Modern Chemistry Research Institute

Study the process of explosive's deflagration to detonation transition based on ignition growth model, and then using AUTODYN-2D software to study the DDT characteristic of TNT under different ignition intension and inhibit situation. The results shows that, the Lee-Tarver model can simulate the explosive's DDT preferable;under weaker ignition intention and inhibit intention situation, the length of inducing combustion was longer.

关键词： Lee-Tarver deflagration to detonation transition Numerical Simulation

来源：评论

学校读者我要写书评

暂无评论

Concerning the Parameterization of Geometric and Criticality Effects on detonation Amplification

引用

AIAA JOURNAL 2025年第2期63卷 783-789页

作者： Millard, Benjamin M. Cuppoletti, Daniel R. Univ Cincinnati Dept Aerosp Engn 450 Mantei Ctr Cincinnati OH 45221 USA Univ Cincinnati Dept Aerosp Engn 462 Mantei Ctr Cincinnati OH 45221 USA

This study investigates the role of geometric effects and detonation criticality on the behavior of a detonation transition through an area expansion of finite length. Three reinitiation behaviors that result in an amplified pressure impulse were observed and are referred to as steady, spike, and endwall amplification. Steady amplification was characterized by an amplification event with a peak pressure impulse 2 times that of the inlet detonation, followed by a near-linear attenuation toward Chapman-Jouguet conditions. Spike amplification displayed a larger peak pressure amplification that was 3 to 5 times greater than the inlet detonation, followed by a rapid and nonlinear attenuation. Endwall behavior represents a Craven-Grieg deflagration to detonation transition scenario. These behaviors are shown to be factors of area expansion ratio and the degree to which the incoming detonation is subcrtical. A decoupling parameter, Psi d, was devised to combine these effects into a single correlation metric. The finite length of the expansion chamber also plays a role in the reinitiation behavior as observed by the endwall reinitiation behavior. A critical chamber length parameter was devised to explain this behavior and then theorized to have a relationship to Psi d with this being explored theoretically and with the limited data set available.

关键词： deflagration Pressure Sensors detonation Waves Fluid Dynamics deflagration to detonation transition Pulse detonation Combustor Gaseous detonations

来源：评论

学校读者我要写书评

暂无评论

Combustion of High-Pressure Hydrogen Diluted Mixtures in ESTHER Shock Tube

引用

JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER 2024年第4期38卷 519-537页

作者： Ferreira, Ricardo Grosso Carvalho, Bernardo Brotas Rodrigues, Rafael Alves, Luis Lemos Goncalves, Bruno da Silva, Mario Lino Marraffa, Lionel Villace, Victor Fernandez Smith, Arthur Univ Lisbon P-1049001 Lisbon Portugal European Space Technol Ctr ESA NL-2200AG Noordwijk Netherlands Old Coach House Emsworth PO10 7DX Hamps England

European Shock Tube for High-Enthalpy Research (ESTHER) is a new state-of-the-art combustion-driven shock tube developed for supporting future ESA planetary exploration missions. Its high-pressure combustion driver sports a unique innovative design where a mixture of He:H2:O2 or N2:H2:O2 gases, filled to pressures up to 100 bar, is ignited by a high-power Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The qualification of this facility driver has allowed for the detailed study of laser-ignited combustion processes at high initial pressures (in the 5-100 bar range), over a series of 100 shots carried out for different configurations and gas mixtures. The influence of the oxygen-to-hydrogen ratio, filling pressure, inert gas dilution, and ignition mode have been studied and are presented in this work. The effects of nitrogen vs helium dilution are also discussed. Filling pressure and helium/nitrogen dilutions have the strongest influence in peak pressure, acoustic oscillation, and combustion velocity. The first two increase, whereas the latter strongly decreases with the filling pressure. Nitrogen diluted shots have drastically lower compression ratios and flame velocity when compared to the helium ones. Acoustic perturbations/instabilities are also found to be stronger. This test campaign allowed the definition of a large range of stable and reproducible firing conditions in deflagration mode, yielding post-combustion pressures up to 660 bar.

关键词： deflagration to detonation transition Planetary Science and Exploration European Space Agency Acoustic Frequencies Shock Tube Hydrogen Combustion Laser Ignition High Pressure Combustion Chambers

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：