Direct-Connect Performance Evaluation of a Valveless Pulse Detonation Engine

Direct-Connect Performance Evaluation of a Valveless Pulse Detonation Engine PDF Author: Nicole K. Wittmers
Publisher:
ISBN: 9781423521754
Category :
Languages : en
Pages : 79

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Book Description
Operational characteristics of a valveless pulse detonation engine system were characterized by experimental measurements of thrust, fuel flow, and internal gas dynamics. The multi-cycle detonation experiments were performed on an axis-symmetric engine geometry operating on an ethylene/air mixture. The detonation diffraction process from a small initiator combustor to a larger diameter main combustor in a continuous airflow configuration was evaluated during multi-cycle operation of a pulse detonation engine and was found to be very successful at initiating combustion of the secondary fuel/air mixture at high frequencies. The configuration was used to demonstrate the benefit of generating an overdriven detonation condition near the diffraction plane for enhanced transmission of the larger combustor. Results have shown that the addition of optical sensors, such as tunable diode lasers, to provide fuel profile data are invaluable for providing high fidelity performance results. The performance results demonstrated the ability of the valveless pulse detonation engine to run at efficiencies similar to valved pulse detonation engine geometries and may be a low-cost alternative to conventional air-breathing propulsion systems.

Direct-Connect Performance Evaluation of a Valveless Pulse Detonation Engine

Direct-Connect Performance Evaluation of a Valveless Pulse Detonation Engine PDF Author: Nicole K. Wittmers
Publisher:
ISBN: 9781423521754
Category :
Languages : en
Pages : 79

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Book Description
Operational characteristics of a valveless pulse detonation engine system were characterized by experimental measurements of thrust, fuel flow, and internal gas dynamics. The multi-cycle detonation experiments were performed on an axis-symmetric engine geometry operating on an ethylene/air mixture. The detonation diffraction process from a small initiator combustor to a larger diameter main combustor in a continuous airflow configuration was evaluated during multi-cycle operation of a pulse detonation engine and was found to be very successful at initiating combustion of the secondary fuel/air mixture at high frequencies. The configuration was used to demonstrate the benefit of generating an overdriven detonation condition near the diffraction plane for enhanced transmission of the larger combustor. Results have shown that the addition of optical sensors, such as tunable diode lasers, to provide fuel profile data are invaluable for providing high fidelity performance results. The performance results demonstrated the ability of the valveless pulse detonation engine to run at efficiencies similar to valved pulse detonation engine geometries and may be a low-cost alternative to conventional air-breathing propulsion systems.

Detonation Control for Propulsion

Detonation Control for Propulsion PDF Author: Jiun-Ming Li
Publisher: Springer
ISBN: 3319689061
Category : Technology & Engineering
Languages : en
Pages : 246

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Book Description
This book focuses on the latest developments in detonation engines for aerospace propulsion, with a focus on the rotating detonation engine (RDE). State-of-the-art research contributions are collected from international leading researchers devoted to the pursuit of controllable detonations for practical detonation propulsion. A system-level design of novel detonation engines, performance analysis, and advanced experimental and numerical methods are covered. In addition, the world’s first successful sled demonstration of a rocket rotating detonation engine system and innovations in the development of a kilohertz pulse detonation engine (PDE) system are reported. Readers will obtain, in a straightforward manner, an understanding of the RDE & PDE design, operation and testing approaches, and further specific integration schemes for diverse applications such as rockets for space propulsion and turbojet/ramjet engines for air-breathing propulsion. Detonation Control for Propulsion: Pulse Detonation and Rotating Detonation Engines provides, with its comprehensive coverage from fundamental detonation science to practical research engineering techniques, a wealth of information for scientists in the field of combustion and propulsion. The volume can also serve as a reference text for faculty and graduate students and interested in shock waves, combustion and propulsion.

Experimental Analysis of Pulse Detonation Engine Performance by Pressure and Momentum Measurements

Experimental Analysis of Pulse Detonation Engine Performance by Pressure and Momentum Measurements PDF Author: J. Kasahara
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description


Performance and Environmental Impact Assessment of Pulse Detonation Based Engine Systems

Performance and Environmental Impact Assessment of Pulse Detonation Based Engine Systems PDF Author: Aaron J. Glaser
Publisher:
ISBN:
Category :
Languages : en
Pages : 241

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Book Description
The acoustic signature of a pulse detonation engine was characterized in both the near-field and far-field regimes. Experimental measurements were performed in an anechoic test facility designed for jet noise testing. Both shock strength and speed were mapped as a function of radial distance and direction from the PDE exhaust plane. It was found that the PDE generated pressure field can be reasonably modeled by a theoretical point-source explosion. The effect of several exit nozzle configurations on the PDE acoustic signature was studies. These included various chevron nozzles, a perforated nozzle, and a set of proprietary noise attenuation mufflers.

Evaluation and Selection of an Efficient Fuel/Air Initiation Strategy for Pulse Detonation Engines

Evaluation and Selection of an Efficient Fuel/Air Initiation Strategy for Pulse Detonation Engines PDF Author:
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 55

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Book Description
Rapid and efficient initiation of hydrocarbon/air mixtures has been identified as one of the critical and enabling technologies for Pulse Detonation Engines (PDEs). Although the NPS Rocket Propulsion Laboratory has successfully demonstrated fuel/air detonations in a valveless pulse detonation engine using ethylene, propane, and JP-10 fuels, past engine designs have relied upon a sensitive fuel/oxygen initiator unit. To realize the increased thermodynamic efficiencies of PDEs and thus compete with ramjets and other supersonic platforms, it is imperative to eliminate any need for supplementary oxygen in an air-breathing PDE design. This thesis examined ignition technologies and initiator designs which did not require auxiliary oxygen, including capacitive discharge systems and the developing technology of Transient Plasma Ignition (TPI). The current NPS pulse detonation engine architecture was modified to evaluate the various ignition strategies in a PDE operating on an ethylene/air mixture at simulated supersonic cruising conditions. Comparisons were based upon ignition success rate, ignition delay time, detonation wave speed, and Deflagration-to-Detonation (DDT) distance. Reliability and performance of the TPI system proved to be superior to conventional ignition systems. Furthermore, successful initiation of a PDE operating at a frequency of up to 40 hertz was demonstrated without the use of supplementary oxygen.

Parametric Cycle Analysis for Pulse Detonation Engines

Parametric Cycle Analysis for Pulse Detonation Engines PDF Author: Haider Hekiri
Publisher:
ISBN: 9780542448836
Category : Aerospace engineering
Languages : en
Pages :

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Book Description
The performance of an ejector-driven pulse detonation engine (PDE) with an afterburner is analytically estimated. In the analysis, the PDE was modeled as a straight tube, closed at the front end and open at the other. A detonation wave starts to travel after it is ignited at the closed end, causing a Chapman-Jouguet detonation wave followed by a Taylor rarefaction to travel to the open end. At that point, rarefaction waves are reflected back to the closed end. The result is a high thrust due to both the primary and secondary flows of the ejector-driven PDE. A theoretical analysis is made to determine the average thrust density and the impulse density per cycle of the primary flow. The mixed flow of the PDE tube and the ejector is then subjected to afterburning. The overall engine performance was eventually derived.

Detonation Initiation Studies and Performance Results for Pulsed Detonation Engine Applications

Detonation Initiation Studies and Performance Results for Pulsed Detonation Engine Applications PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 11

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Book Description
An in-house computational and experimental program to investigate and develop an air breathing pulse detonation engine (PDE) that uses a practical fuel (kerosene based, fleet-wide use, JP type) is currently underway at the Combustion Sciences Branch of the Turbine Engine Division of the Air Force Research Laboratory (AFRL/PRTS). PDE's have the potential of high thrust, low weight, low cost, high scalability, and wide operating range, but several technological hurdles must be overcome before a practical engine can be designed. This research effort involves investigating such critical issues as: detonation initiation and propagation; valving, timing and control; instrumentation and diagnostics; purging, heat transfer, and repetition rate; noise and multi-tube effects; detonation and deflagration to detonation transition modeling; and performance prediction and analysis. An innovative, four-detonation-tube engine design is currently in test and evaluation. Preliminary data are obtained with premixed hydrogen/air as the fuel/oxidizer to demonstrate proof of concept and verify models. Techniques for initiating detonations in hydrogen/air mixtures are developed without the use of oxygen enriched air. An overview of the AFRL/PRTS PDE development research program and hydrogen/air results are presented.

Performance Analysis of a Pulse Detonation Device as an After-burner

Performance Analysis of a Pulse Detonation Device as an After-burner PDF Author: M. A. Mawid
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Book Description


Intake Flow Analysis of a Pulsed Detonation Engine

Intake Flow Analysis of a Pulsed Detonation Engine PDF Author: Joshua Amadeus Strafaccia
Publisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 78

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Book Description
A CFD program is converted and modified to explore unsteady flow within the intake system of a pulse detonation engine (PDE). Using a quasi-one-dimensional approach the program provides insight into the unsteady nature of localized equivalence ratios to include their effects on PDE performance. The original FORTRAN program is converted into the MATLAB architecture, taking full advantage of user availability and post processing convenience. The converted program was validated against the original program and modified to include a primitive intake manifold system with a single fuel injector located approximately 10 feet upstream of the primary intake valve. Constant fuel mass flow rate at the injector end creates local variations in equivalence ratio throughout the PDE that may have significant impact on overall engine performance. The results of the current thesis research suggest that performance effects of up to 21% can be attributed to non-uniform fuel distribution throughout the detonation process and are most prevalent at lower frequencies and fill ratios.

A State of Art Review on Thermodynamics Performance Analysis in Pulse Detonation Combustor

A State of Art Review on Thermodynamics Performance Analysis in Pulse Detonation Combustor PDF Author: Pinku Debnath
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 0

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Book Description
Pulse detonation engines (PDEs) are most exciting for future propulsion generation. Detonation combustion in pulse detonation combustor is an energetic combustion process which is differs from other combustion process. The detonation wave propagation in detonation tube is a pulse setting combustion phenomena. Detonation combustion process is thousands times faster than deflagration combustion process. PDE utilizes several pulse of detonation wave to produce propulsive force. The potential applications of PDEs are drastically reduces the cost of orbit transfer vehicle system and flying mode applications. Of course it can be used as ground level applications also. Draw back are DDT in shortest possible time in the combustor. In this regards, worldwide researchers are focusing on scientific and technical issues related to improvement of PDC. The present chapter deals with review study on detonation combustion process, historical overview on chemical kinetics, calorimetric and entropy transport, energy and exergy analysis and factor effecting on deflagration to detonation transition with recommendable future research.