Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721570782
Category :
Languages : en
Pages : 34
Book Description
This paper presents results for a single-pulse detonation tube wherein the effects of high temperature dissociation and the subsequent recombination influence the sensible heat release available for providing propulsive thrust. The study involved the use of ethylene and air at equivalence ratios of 0.7 and 1.0. The real gas effects on the sensible heat release were found to be significantly large so as to have an impact on the thrust, impulse and fuel consumption of a PDE. Povinelli, Louis A. and Yungster, Shaye Glenn Research Center NASA/TM-2003-212211, E-13819, NAS 1.15:212211, AIAA Paper 2003-0712, ICOMP-2003-02
Real Gas Effects on the Performance of Hydrocarbon-Fueled Pulse Detonation Engines
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721570782
Category :
Languages : en
Pages : 34
Book Description
This paper presents results for a single-pulse detonation tube wherein the effects of high temperature dissociation and the subsequent recombination influence the sensible heat release available for providing propulsive thrust. The study involved the use of ethylene and air at equivalence ratios of 0.7 and 1.0. The real gas effects on the sensible heat release were found to be significantly large so as to have an impact on the thrust, impulse and fuel consumption of a PDE. Povinelli, Louis A. and Yungster, Shaye Glenn Research Center NASA/TM-2003-212211, E-13819, NAS 1.15:212211, AIAA Paper 2003-0712, ICOMP-2003-02
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721570782
Category :
Languages : en
Pages : 34
Book Description
This paper presents results for a single-pulse detonation tube wherein the effects of high temperature dissociation and the subsequent recombination influence the sensible heat release available for providing propulsive thrust. The study involved the use of ethylene and air at equivalence ratios of 0.7 and 1.0. The real gas effects on the sensible heat release were found to be significantly large so as to have an impact on the thrust, impulse and fuel consumption of a PDE. Povinelli, Louis A. and Yungster, Shaye Glenn Research Center NASA/TM-2003-212211, E-13819, NAS 1.15:212211, AIAA Paper 2003-0712, ICOMP-2003-02
Ramjet Engines
Author: Mikhail Makarovich Bondari͡u︡k
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 466
Book Description
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 466
Book Description
Scramjet Propulsion
Author: E. T. Curran
Publisher: AIAA
ISBN: 9781600864414
Category : Airplanes
Languages : en
Pages : 1354
Book Description
Publisher: AIAA
ISBN: 9781600864414
Category : Airplanes
Languages : en
Pages : 1354
Book Description
High-Speed Flight Propulsion Systems
Author: S. N. B. Murthy
Publisher: AIAA
ISBN: 9781600863912
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 558
Book Description
Annotation Leading researchers provide a cohesive treatment of the complex issues in high-speed propulsion, as well as introductions to the current capabilities for addressing several fundamental aspects of high-speed vehicle propulsion development. Includes more than 380 references, 290 figures and tables, and 185 equations.
Publisher: AIAA
ISBN: 9781600863912
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 558
Book Description
Annotation Leading researchers provide a cohesive treatment of the complex issues in high-speed propulsion, as well as introductions to the current capabilities for addressing several fundamental aspects of high-speed vehicle propulsion development. Includes more than 380 references, 290 figures and tables, and 185 equations.
Synthesis and Characterization of Advanced Materials
Author: Michael A. Serio
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 296
Book Description
These papers by leading experts look at current methods for synthesizing new materials. The methods presented include chemical vapor deposition synthesis, solution synthesis, pyrolysis and combustion synthesis, and polymer synthesis. Featuring in-depth coverage of ceramic materials, the volume also discusses group III nitrides, fullerenes, and ferroelectrics.
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 296
Book Description
These papers by leading experts look at current methods for synthesizing new materials. The methods presented include chemical vapor deposition synthesis, solution synthesis, pyrolysis and combustion synthesis, and polymer synthesis. Featuring in-depth coverage of ceramic materials, the volume also discusses group III nitrides, fullerenes, and ferroelectrics.
Effects of Fuel Distribution on Detonation Tube Performance
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781720484080
Category :
Languages : en
Pages : 72
Book Description
A pulse detonation engine (PDE) uses a series of high frequency intermittent detonation tubes to generate thrust. The process of filling the detonation tube with fuel and air for each cycle may yield non-uniform mixtures. Lack of mixture uniformity is commonly ignored when calculating detonation tube thrust performance. In this study, detonation cycles featuring idealized non-uniform H2/air mixtures were analyzed using the SPARK two-dimensional Navier-Stokes CFD code with 7-step H2/air reaction mechanism. Mixture non-uniformities examined included axial equivalence ratio gradients, transverse equivalence ratio gradients, and partially fueled tubes. Three different average test section equivalence ratios (phi), stoichiometric (phi = 1.00), fuel lean (phi = 0.90), and fuel rich (phi = 1.10), were studied. All mixtures were detonable throughout the detonation tube. It was found that various mixtures representing the same test section equivalence ratio had specific impulses within 1 percent of each other, indicating that good fuel/air mixing is not a prerequisite for optimal detonation tube performance.Perkins, Hugh DouglasGlenn Research CenterNAVIER-STOKES EQUATION; PULSE DETONATION ENGINES; FUEL COMBUSTION; FUEL-AIR RATIO; DETONATION; DETONABLE GAS MIXTURES; DETONATION WAVES; TEST CHAMBERS; SPECIFIC IMPULSE; THRUST; NONUNIFORMITY; COMPUTATIONAL FLUID DYNAMICS
Publisher: Createspace Independent Publishing Platform
ISBN: 9781720484080
Category :
Languages : en
Pages : 72
Book Description
A pulse detonation engine (PDE) uses a series of high frequency intermittent detonation tubes to generate thrust. The process of filling the detonation tube with fuel and air for each cycle may yield non-uniform mixtures. Lack of mixture uniformity is commonly ignored when calculating detonation tube thrust performance. In this study, detonation cycles featuring idealized non-uniform H2/air mixtures were analyzed using the SPARK two-dimensional Navier-Stokes CFD code with 7-step H2/air reaction mechanism. Mixture non-uniformities examined included axial equivalence ratio gradients, transverse equivalence ratio gradients, and partially fueled tubes. Three different average test section equivalence ratios (phi), stoichiometric (phi = 1.00), fuel lean (phi = 0.90), and fuel rich (phi = 1.10), were studied. All mixtures were detonable throughout the detonation tube. It was found that various mixtures representing the same test section equivalence ratio had specific impulses within 1 percent of each other, indicating that good fuel/air mixing is not a prerequisite for optimal detonation tube performance.Perkins, Hugh DouglasGlenn Research CenterNAVIER-STOKES EQUATION; PULSE DETONATION ENGINES; FUEL COMBUSTION; FUEL-AIR RATIO; DETONATION; DETONABLE GAS MIXTURES; DETONATION WAVES; TEST CHAMBERS; SPECIFIC IMPULSE; THRUST; NONUNIFORMITY; COMPUTATIONAL FLUID DYNAMICS
Optimal Area Profiles for Ideal Single Nozzle Air-Breathing Pulse Detonation Engines
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721584437
Category :
Languages : en
Pages : 32
Book Description
The effects of cross-sectional area variation on idealized Pulse Detonation Engine performance are examined numerically. A quasi-one-dimensional, reacting, numerical code is used as the kernel of an algorithm that iteratively determines the correct sequencing of inlet air, inlet fuel, detonation initiation, and cycle time to achieve a limit cycle with specified fuel fraction, and volumetric purge fraction. The algorithm is exercised on a tube with a cross sectional area profile containing two degrees of freedom: overall exit-to-inlet area ratio, and the distance along the tube at which continuous transition from inlet to exit area begins. These two parameters are varied over three flight conditions (defined by inlet total temperature, inlet total pressure and ambient static pressure) and the performance is compared to a straight tube. It is shown that compared to straight tubes, increases of 20 to 35 percent in specific impulse and specific thrust are obtained with tubes of relatively modest area change. The iterative algorithm is described, and its limitations are noted and discussed. Optimized results are presented showing performance measurements, wave diagrams, and area profiles. Suggestions for future investigation are also discussed. Paxson, Daniel E. Glenn Research Center NASA/TM-2003-212496, AIAA Paper 2003-4512, NAS 1.15:212496, E-14057
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721584437
Category :
Languages : en
Pages : 32
Book Description
The effects of cross-sectional area variation on idealized Pulse Detonation Engine performance are examined numerically. A quasi-one-dimensional, reacting, numerical code is used as the kernel of an algorithm that iteratively determines the correct sequencing of inlet air, inlet fuel, detonation initiation, and cycle time to achieve a limit cycle with specified fuel fraction, and volumetric purge fraction. The algorithm is exercised on a tube with a cross sectional area profile containing two degrees of freedom: overall exit-to-inlet area ratio, and the distance along the tube at which continuous transition from inlet to exit area begins. These two parameters are varied over three flight conditions (defined by inlet total temperature, inlet total pressure and ambient static pressure) and the performance is compared to a straight tube. It is shown that compared to straight tubes, increases of 20 to 35 percent in specific impulse and specific thrust are obtained with tubes of relatively modest area change. The iterative algorithm is described, and its limitations are noted and discussed. Optimized results are presented showing performance measurements, wave diagrams, and area profiles. Suggestions for future investigation are also discussed. Paxson, Daniel E. Glenn Research Center NASA/TM-2003-212496, AIAA Paper 2003-4512, NAS 1.15:212496, E-14057
Development of a Gas-Fed Pulse Detonation Research Engine
Author: R. J. Litchford
Publisher:
ISBN:
Category : Detonation waves
Languages : en
Pages : 52
Book Description
Publisher:
ISBN:
Category : Detonation waves
Languages : en
Pages : 52
Book Description
Diamond Based Composites
Author: Mark A. Prelas
Publisher: Springer Science & Business Media
ISBN: 9401155925
Category : Technology & Engineering
Languages : en
Pages : 378
Book Description
Diamond-based composites, with their advantages of hardness, high Young's modulus and the like, have demonstrated new and unusual features, such as stability to high temperatures and pressure shocks and a large internal surface that can be controlled to offer customised electrical, magnetic and optical properties, leading to efficient filters, absorbents, sensors and other tools for environmental control and monitoring. The current book covers the synthesis of materials, their characterization and properties, trends in high pressure and high temperature technologies, low pressure technologies, basic principles of DBC material science, and future developments in electronics, optics, industrial tools and components, biotechnology, and medicine. Wide band-gap materials are considered, ranging from molecular clusters, nanophase materials, growth, processing and synthesis. The processing of composite based materials can be classified into six basic methods: in situ growth, high pressure/high temperature catalytic conversion; mix and sinter (c-BN plus metal-ceramic polymer mix); direct sintering; direct polymorphic conversion; shock detonation; and SHS sintering.
Publisher: Springer Science & Business Media
ISBN: 9401155925
Category : Technology & Engineering
Languages : en
Pages : 378
Book Description
Diamond-based composites, with their advantages of hardness, high Young's modulus and the like, have demonstrated new and unusual features, such as stability to high temperatures and pressure shocks and a large internal surface that can be controlled to offer customised electrical, magnetic and optical properties, leading to efficient filters, absorbents, sensors and other tools for environmental control and monitoring. The current book covers the synthesis of materials, their characterization and properties, trends in high pressure and high temperature technologies, low pressure technologies, basic principles of DBC material science, and future developments in electronics, optics, industrial tools and components, biotechnology, and medicine. Wide band-gap materials are considered, ranging from molecular clusters, nanophase materials, growth, processing and synthesis. The processing of composite based materials can be classified into six basic methods: in situ growth, high pressure/high temperature catalytic conversion; mix and sinter (c-BN plus metal-ceramic polymer mix); direct sintering; direct polymorphic conversion; shock detonation; and SHS sintering.
Thermal Load Considerations for Detonative Combustion-Based Gas Turbine Engines
Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721666454
Category :
Languages : en
Pages : 34
Book Description
An analysis was conducted to assess methods for, and performance implications of, cooling the passages (tubes) of a pulse detonation-based combustor conceptually installed in the core of a gas turbine engine typical of regional aircraft. Temperature-limited material stress criteria were developed from common-sense engineering practice, and available material properties. Validated, one-dimensional, numerical simulations were then used to explore a variety of cooling methods and establish whether or not they met the established criteria. Simulation output data from successful schemes were averaged and used in a cycle-deck engine simulation in order to assess the impact of the cooling method on overall performance. Results were compared to both a baseline engine equipped with a constant-pressure combustor and to one equipped with an idealized detonative combustor. Major findings indicate that thermal loads in these devices are large, but potentially manageable. However, the impact on performance can be substantial. Nearly one half of the ideally possible specific fuel consumption (SFC) reduction is lost due to cooling of the tubes. Details of the analysis are described, limitations are presented, and implications are discussed. Paxson, Daniel E. and Perkins, H. Douglas Glenn Research Center NASA/TM-2004-213190, AIAA Paper 2004-3396, E-14689
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721666454
Category :
Languages : en
Pages : 34
Book Description
An analysis was conducted to assess methods for, and performance implications of, cooling the passages (tubes) of a pulse detonation-based combustor conceptually installed in the core of a gas turbine engine typical of regional aircraft. Temperature-limited material stress criteria were developed from common-sense engineering practice, and available material properties. Validated, one-dimensional, numerical simulations were then used to explore a variety of cooling methods and establish whether or not they met the established criteria. Simulation output data from successful schemes were averaged and used in a cycle-deck engine simulation in order to assess the impact of the cooling method on overall performance. Results were compared to both a baseline engine equipped with a constant-pressure combustor and to one equipped with an idealized detonative combustor. Major findings indicate that thermal loads in these devices are large, but potentially manageable. However, the impact on performance can be substantial. Nearly one half of the ideally possible specific fuel consumption (SFC) reduction is lost due to cooling of the tubes. Details of the analysis are described, limitations are presented, and implications are discussed. Paxson, Daniel E. and Perkins, H. Douglas Glenn Research Center NASA/TM-2004-213190, AIAA Paper 2004-3396, E-14689