Search Results (1 - 12 of 12 Results)

Sort By  
Sort Dir
 
Results per page  

Zhu, Yonry RApplications and Modeling of Non-Thermal Plasmas
Bachelor of Science (BS), Ohio University, 2018, Engineering Physics
This thesis focuses on validation of a 0D plasma kinetic model and its subsequent use as an explanatory tool to support the results of hot-fire tests of a plasma assisted rotating detonation combustor. The plasma model predictions showed good agreement with experimentally measured values of various ground state species number densities, vibrationally excited N2 number densities, plasma temperatures, and ignition delay times. Once validated, the plasma model was combined with a ZND detonation model and semi-empirical correlation to determine the effects of a non-thermal plasma on the reduction of the detonation cell size for an H2 - air mixture. The modeling results showed that non-thermal plasma significantly reduces the detonation cell size. This effect is most pronounced at lean conditions, where the model predicted a reduction in cell size by a factor of more than 100. For stoichiometric and rich conditions, the cell size reduction was around a factor of 5. An investigation was conducted to determine the viability of using a non-thermal plasma to expand the operating regime of a rotating detonation combustor. The plasma was produced with a nanosecond pulse generator connected to a ceramic and metal centerbody electrode. Hot-fire testing results showed that the plasma causes detonation onset in conditions that would otherwise not support detonation. This effect was most prominent at near-stoichiometric conditions, with a reduced effect for richer or leaner mixtures.

Committee:

David Burnette (Advisor)

Subjects:

Aerospace Engineering; Mechanical Engineering; Plasma Physics

Keywords:

non-thermal plasma; plasma assisted combustion; nanosecond pulsed plasma; plasma modeling; detonation combustion; rotating detonation combustor; detonation;

St. George, AndrewDevelopment and Testing of Pulsed and Rotating Detonation Combustors
PhD, University of Cincinnati, 2016, Engineering and Applied Science: Aerospace Engineering
Detonation is a self-sustaining, supersonic, shock-driven, exothermic reaction. Detonation combustion can theoretically provide significant improvements in thermodynamic efficiency over constant pressure combustion when incorporated into existing cycles. To harness this potential performance benefit, countless studies have worked to develop detonation combustors and integrate these devices into existing systems. This dissertation consists of a series of investigations on two types of detonation combustors: the pulse detonation combustor (PDC) and the rotating detonation combustor (RDC).

In the first two investigations, an array of air-breathing PDCs is integrated with an axial power turbine. The system is initially operated with steady and pulsed cold air flow to determine the effect of pulsed flow on turbine performance. Various averaging approaches are employed to calculate turbine efficiency, but only flow-weighted (e.g., mass or work averaging) definitions have physical significance. Pulsed flow turbine efficiency is comparable to steady flow efficiency at high corrected flow rates and low rotor speeds. At these conditions, the pulse duty cycle expands and the variation of the rotor incidence angle is constrained to a favorable range. The system is operated with pulsed detonating flow to determine the effect of frequency, fill fraction, and rotor speed on turbine performance. For some conditions, output power exceeds the maximum attainable value from steady constant pressure combustion due to a significant increase in available power from the detonation products. However, the turbine component efficiency estimated from classical thermodynamic analysis is four times lower than the steady design point efficiency. Analysis of blade angles shows a significant penalty due to the detonation, fill, and purge processes simultaneously imposed on the rotor.

The latter six investigations focus on fundamental research of the RDC concept. A specially-tailored RDC data analysis approach is developed, which employs cross-correlations to detect the combustor operating state as it evolves during a test. This method enables expedient detection of the operating state from sensors placed outside the combustor, and can also identify and quantify instabilities. An investigation is conducted on a tangentially-injecting initiator tube to characterize the RDC ignition process. Maximum energy deposition for this ignition method is an order of magnitude lower than the required energy for direct initiation, and detonation develops via a deflagration-to-detonation transition process. Stable rotating detonation is preceded by a transitory onset phase with a stochastic duration, which appears to be a function of the reactant injection pressure ratio.

Hydrogen-ethylene fuel blends are explored as an interim strategy to transition to stable detonation in ethylene-air mixtures. While moderate hydrogen addition enables stable operation, removal of the supplemental hydrogen triggers instability and failure. Chemical kinetic analysis indicates that elevated reactant pressure is far more significant than hydrogen addition, and suggests that the stabilizing effect of hydrogen is physical, rather than kinetic. The role of kinetic effects (e.g., cell width) is also assessed, using H2-O2-N2 mixtures. Detonation is observed when the normalized channel width exceeds the classical limit of wch/λ = 0.5, and the number of detonations increases predictably when the detonation perimeter exceeds a critical value.

Committee:

Ephraim Gutmark, Ph.D. D.Sc. (Committee Chair); Shaaban Abdallah, Ph.D. (Committee Member); David Munday, Ph.D. (Committee Member); Mark Turner, Sc.D. (Committee Member)

Subjects:

Aerospace Materials

Keywords:

detonation;rotating detonation combustor;pulse detonation combustor;turbine;initiation;cell width

Driscoll, Robert BInvestigation of Sustained Detonation Devices: the Pulse Detonation Engine-Crossover System and the Rotating Detonation Engine System
PhD, University of Cincinnati, 2016, Engineering and Applied Science: Aerospace Engineering
An experimental study is conducted on a Pulse Detonation Engine-Crossover System to investigate the feasibility of repeated, shock-initiated combustion and characterize the initiation performance. A PDE-crossover system can decrease deflagration-to-detonation transition length while employing a single spark source to initiate a multi-PDE system. Visualization of a transferred shock wave propagating through a clear channel reveals a complex shock train behind the leading shock. Shock wave Mach number and decay rate remains constant for varying crossover tube geometries and operational frequencies. A temperature gradient forms within the crossover tube due to forward flow of high temperature ionized gas into the crossover tube from the driver PDE and backward flow of ionized gas into the crossover tube from the driven PDE, which can cause intermittent auto-ignition of the driver PDE. Initiation performance in the driven PDE is strongly dependent on initial driven PDE skin temperature in the shock wave reflection region. An array of detonation tubes connected with crossover tubes is developed using optimized parameters and successful operation utilizing shock-initiated combustion through shock wave reflection is achieved and sustained. Finally, an air-breathing, PDE-Crossover System is developed to characterize the feasibility of shock-initiated combustion within an air-breathing pulse detonation engine. The initiation effectiveness of shock-initiated combustion is compared to spark discharge and detonation injection through a pre-detonator. In all cases, shock-initiated combustion produces improved initiation performance over spark discharge and comparable detonation transition run-up lengths relative to pre-detonator initiation. A computational study characterizes the mixing processes and injection flow field within a rotating detonation engine. Injection parameters including reactant flow rate, reactant injection area, placement of the fuel injection, and fuel injection distribution are varied to assess the impact on mixing. Decreasing reactant injection areas improves fuel penetration into the cross-flowing air stream, enhances turbulent diffusion of the fuel within the annulus, and increases local equivalence ratio and fluid mixedness. Staggering fuel injection holes produces a decrease in mixing when compared to collinear fuel injection. Finally, emulating nozzle integration by increasing annulus back-pressure increases local equivalence ratio in the injection region due to increased convection residence time.

Committee:

Ephraim Gutmark, Ph.D. D.Sc. (Committee Chair); Shaaban Abdallah, Ph.D. (Committee Member); David Munday, Ph.D. (Committee Member); Mark Turner, Sc.D. (Committee Member)

Subjects:

Aerospace Materials

Keywords:

Detonation;Pulse Detonation Engine;Rotating Detonation Engine;PDE-Crossover System;Reactant Injection Mixing

RAGHUPATHY, ARUN PRAKASHA NUMERICAL STUDY OF DETONATION AND PLUME DYNAMICS IN A PULSED DETONATION ENGINE
MS, University of Cincinnati, 2005, Engineering : Mechanical Engineering
The Pulse Detonation Engine (PDE) is considered to be the propulsion system of future air vehicles. The objective of the present study is to understand the variation in the external flow field of a PDE during take-off and cruise conditions. To do this, the underlying concept of a PDE, namely, detonation is simulated using finite-rate chemistry. Performance of four chemical mechanisms in predicting detonation quantities is evaluated. The global mechanisms predict the detonation quantities with the least error, and are used for simulating detonation in a PDE. Comparative analysis of the plume dynamics for different equivalence ratios reveals a similar trend in the temperature distribution for both mixtures, but not in the pressure distribution. A sub-atmospheric zone is identified, which is largely responsible for the blowdown process. The analysis of the external flow field provides guidelines for the optimum placement of the turbine in the case of a Hybrid PDE.

Committee:

Dr. Urmila Ghia (Advisor)

Subjects:

Engineering, Aerospace

Keywords:

Pulse Detonation Engine; Chemical Kinetics; Detonation Modeling; Combustion;

ALLGOOD, DANIEL CLAYAN EXPERIMENTAL AND COMPUTATIONAL STUDY OF PULSE DETONATION ENGINES
PhD, University of Cincinnati, 2004, Engineering : Aerospace Engineering
Research studies investigating the performance optimization and fundamental physics of pulse detonation engines (PDE) were performed. Experimental and computational methods were developed and used in these studies. Four primary research tasks were established. The first research task was to obtain detailed measurements of a PDE exhaust plume for a variety of operating conditions and engine geometries. Shadowgraph visualizations in conjunction with OH* and CH* chemiluminescence imaging were performed. The PDE plume visualizations provided a means of studying the flowfield behavior associated with PDE ejectors and exhaust nozzles as well as providing explanations for the observed acoustic behavior of the PDE. The second research task was to quantify the thrust augmentation of PDE-ejectors. Significant losses in the ejector entrainment were observed when the ejector inlet was not of an aerodynamic shape. Performance measurements of axisymmetric PDE-ejector systems showed the thrust augmentation to be a strong function of the ejector length-to-diameter ratio, ejector axial placement and PDE fill-fraction. Peak thrust augmentation levels were recorded to be approximately 20% for a straight-ejector and 65% for a diverging-ejector. An increase in thrust augmentation was obtained with a reduction in fill-fraction. Performance measurements of PDE converging and diverging exhaust nozzles were also obtained at various operating conditions of the engine. At low fill-fractions, both converging and diverging exhaust nozzles were observed to adversely affect the PDE performance. At fill-fractions close to and greater than 1, the converging nozzles showed the best performance due to increased PDE blow-down time (maintaining PDE chamber pressure) and acceleration of the primarily subsonic exhaust flow. The fourth research task was to perform a detailed far-field study of PDE acoustics. The acoustic energy of the PDE blast-wave was observed to be highly directional. Very good agreement was obtained between the experimental data and model predictions for the radial decay in peak pressure as well as the characteristic times of the blast-wave pulses. Converging exhaust nozzles were observed to produce a global reduction in PDE noise, while diverging nozzles affected only the downstream noise.

Committee:

Dr. Ephraim Gutmark (Advisor)

Subjects:

Engineering, Aerospace

Keywords:

pulse detonation engine; detonation; nozzles; ejectors; acoustics; shadowgraph; blast waves; computational fluid dynamics; chemiluminescence

Naples, Andrew G.Detonation Initiation in a Pulse Detonation Engine with Elevated Initial Pressures
Master of Science, The Ohio State University, 2008, Mechanical Engineering
An experimental study was done to examine the effects of elevated initial tube pressure in the PDE. Measured parameters were the ignition time, DDT run-up distance, DDT times, and C-J velocity. Mixed with air, three fuels, i.e., aviation gasoline, ethylene, and hydrogen, were tested at various initial pressures and equivalence ratios. A stock automotive ignition system was employed, along with a transient and thermal plasma ignition system, to quantify the benefits of each. Measured results show a reduction in the ignition time of roughly 50% and in the DDT distance of roughly 30%, for all three fuels at an initial tube pressure of 3 atmospheres. At roughly 2 atmospheres of initial pressure the thermal plasma ignition system showed no benefit over the stock automotive ignition system. In addition to the experimental results, a brief Chemkin analysis was done to model the stock automotive ignition system.

Committee:

Sheng-Tao John Yu, PhD (Advisor); Igor Adamovich, PhD (Committee Member); Frederick Schauer, PhD (Committee Member)

Subjects:

Engineering; Mechanical Engineering

Keywords:

Aircraft Propulsion; Pulse Detonation; Detonation; PDE

Driscoll, Robert BEXPERIMENTAL INVESTIGATION OF SHOCK TRANSFER AND SHOCK INITIATED DETONATION IN A DUAL PULSE DETONATION ENGINE CROSSOVER SYSTEM
MS, University of Cincinnati, 2013, Engineering and Applied Science: Aerospace Engineering
An experimental investigation was carried out to study the travel of a shockwave through a crossover tube and analyze the ability to cause shock initiated detonation. This concept involved using a pulse detonation engine (PDE) as a driver to produce a shockwave. This shockwave travelled to a second, adjacent detonation tube. In this driven PDE, the shockwave would reflect off of the inner, concaved wall causing shock initiated detonation. A preliminary study using a dual PDE crossover tube system yielded experimental results that have shown successful cases where reflected shockwaves are used to cause direct detonation initiation. For that study, two reactant-filled PDEs were connected through an air-filled crossover tube, with the driver PDE ignited. High speed pressure sensors were used to verify combustion wave speeds. Preliminary results showed shock initiated detonation to be possible when using a dual PDE crossover system. Additionally, a parametric study was carried out to investigate shock initiated detonation within a dual PDE crossover system. Shockwaves produced by a driver PDE were carried through crossover tubes of varying lengths and bends to the driven PDE. The driving PDE was ignited using a traditional spark plug. From burning wave speeds measured by high speed pressure sensors, results have shown a transferred shockwave reflecting off the wall of the driven PDE will achieve shock initiated detonation. However, the results have also yielded cases where the initial shockwave reflection does not directly initiate a detonation in the driven PDE, but rather causes ignition leading to accelerated deflagration to detonation transition (DDT). Overall results have shown that for specific tube geometries, there is a maximum effective crossover tube length in which shock initiated detonation is possible. Furthermore, shadowgraph techniques were used to capture and study the propagation of a transferred shockwave produced by a driving detonation tube. To accomplish this, a single PDE was used to drive a shockwave through a clear, composite, transfer tube. Shock attenuation data was gathered during this study. This information created a relation between shock strength and crossover tube length. Also, regardless of the filling conditions of the transfer tube, all shock waves reach similar attenuation rates at relatively the same transfer tube length. Moreover, a vortex plume study was carried out to capture and study shock Mach number decay as a planar shockwave transitions to a spherical shockwave at the exit of a transfer tube. Transfer tubes of varying lengths and bends were used in the study. General Attenuation Law was used to further understand the relation between spherical shock strength and propagation distance. Results showed that a bend placed at the end of the transfer tube enhances the strength of a planar shockwave. Finally, with the aid of the two shadowgraph experiments, a correlation between maximum effective crossover tube length and shock strength was created. Performance in the driven PDE begins to decrease when the incident shock strength decreases below M = 2.0.

Committee:

Ephraim Gutmark, Ph.D., D.Sc. (Committee Chair); David Munday, Ph.D. (Committee Member); Mark Turner, Sc.D. (Committee Member)

Subjects:

Aerospace Materials

Keywords:

Pulse Detonation Engine;Detonation;Crossover

He, HaoNumerical simulations of unsteady flows in a pulse detonation engine by the conservation element and solution element method
Doctor of Philosophy, The Ohio State University, 2006, Mechanical Engineering
This dissertation is focused on a numerical framework for time-accurate solutions of high-speed unsteady flows with applications to flows of a Pulse Detonation Engine (PDE). The space-time Conservation Element and Solution Element (CESE) method employed is a novel numerical method for time-accurate solutions of nonlinear hyperbolic equations. As a part of the present result, a suite of two- and three-dimensional CESE codes has been developed. The computer codes are fully parallelized based on domain decomposition with Message Passing Interface (MPI) for data communication. The codes have been applied to analyze various flow fields of the PDE concept. First, numerical results of one-, two- and three-dimensional detonation waves are reported. The chemical reactions were modeled by a one-step, finite-rate, irreversible global reaction. The classical Zeldovich, von Neumann, and Doering (ZND) analytical solution was used to set up the initial conditions as well as for code validation. In the three-dimensional calculations, detonations in square, round, and annular tubes at different sizes were successfully simulated. Salient features of detonation waves were crisply resolved. Second, as a promising detonation initiation means, implosion with shock focusing was investigated. In two-dimensional calculations, we found a double-implosion mechanism in a successful detonation initiation process. Third, the plume dynamics of a PDE fueled by propane/air mixtures were studied to support the prototype development at NASA Glenn Research Center (GRC). Numerical results show that in each PDE cycle the engine is actively producing thrust forces only in about 6% of one cycle time period. The rest of the time is occupied by the blow-down and refueling processes. Since the PDE tube is always open, the processes depend on the flow conditions outside the PDE tube. In the near-field plume, complex shock/shock and shock/vortex interactions were found. In the far field, a spherical expansion wave is the dominant flow feature. This dissertation work is synergy of a very accurate and efficient CFD method, i.e., the CESE method, and the modern parallel computing technology. This approach could point to a new direction for high-fidelity simulations of complex flow fields of advanced propulsion systems.

Committee:

Sheng-Tao Yu (Advisor)

Subjects:

Engineering, Mechanical

Keywords:

Detonation; Pulse Detonation Engine; The CESE Method; Computational Fluid Dynamics; Numerical Simulation; Parallel Computing

GLASER, AARON J.PERFORMANCE AND ENVIRONMENTAL IMPACT ASSESSMENT OF PULSE DETONATION BASED ENGINE SYSTEMS
PhD, University of Cincinnati, 2007, Engineering : Aerospace Engineering
Experimental research was performed to investigate the feasibility of using pulse detonation based engine systems for practical aerospace applications. In order to carry out this work a new pulse detonation combustion research facility was developed at the University of Cincinnati. This research covered two broad areas of application interest. The first area is pure PDE applications where the detonation tube is used to generate an impulsive thrust directly. The second focus area is on pulse detonation based hybrid propulsion systems. Within each of these areas various studies were performed to quantify engine performance. Comparisons of the performance between detonation and conventional deflagration based engine cycles were made. Fundamental studies investigating detonation physics and flow dynamics were performed in order to gain physical insight into the observed performance trends. Experimental studies were performed on PDE-driven straight and diverging ejectors to determine the system performance. Ejector performance was quantified by thrust measurements made using a damped thrust stand. The effects of PDE operating parameters and ejector geometric parameters on thrust augmentation were investigated. For all cases tested, the maximum thrust augmentation is found to occur at a downstream ejector placement. The optimum ejector geometry was determined to have an overall length of LEJECT/DEJECT=5.61, including an intermediate-straight section length of LSTRT/DEJECT=2, and diverging exhaust section with 4 deg half-angle. A maximum thrust augmentation of 105% was observed while employing the optimized ejector geometry and operating the PDE at a fill-fraction of 0.6 and a frequency of 10 Hz. When operated at a fill-fraction of 1.0 and a frequency of 30 Hz, the thrust augmentation of the optimized PDE-driven ejector system was observed to be 71%. Static pressure was measured along the interior surface of the ejector, including the inlet and exhaust sections. The diverging ejector pressure distribution shows that the diverging section acts as a subsonic diffuser. To provide a better explanation of the observed performance trends, shadowgraph images of the detonation wave and starting vortex interacting with the ejector inlet were obtained. 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. Experimental studies were carried out to investigate the performance of a hybrid propulsion system integrating an axial flow turbine with multiple pulse detonation combustors. The integrated system consisted of a circular array of six pulse detonation combustor (PDC) tubes exhausting through an axial flow turbine. Turbine component performance was quantified by measuring the amount of power generated by the turbine section. Direct comparisons of specific power output and turbine efficiency between a PDC-driven turbine and a turbine driven by steady-flow combustors were made. It was found that the PDC-driven turbine had comparable performance to that of a steady-burner-driven turbine across the operating map of the turbine.

Committee:

Dr. Ephraim Gutmark (Advisor)

Keywords:

Pulse Detonation Engines

Wang, BaoNumerical Simulation of Detonation Initiation by the Space-Time Conservation Element and Solution Element Method
Doctor of Philosophy, The Ohio State University, 2010, Mechanical Engineering
This dissertation is focused on the numerical simulation of the detonation initiation process. The space-time Conservation Element and Solution Element (CESE) method, a novel numerical method for time-accurate solutions of nonlinear hyperbolic equations, is extended to model conservation laws with stiff source terms for the detonation initiation process with multiple-step, finite-rate chemistry. The first part of the dissertation illustrates the numerical framework for unsteady chemically reacting flows by incorporating multiple-step, finite-rate chemical mechanisms using the CESE method. One- and two-dimensional solvers have been developed. Extensive code validation and verification are provided for the one- and two-dimensional CESE solvers. The second part focuses on the numerical investigation of the detonation initiation process. The numerical framework is first applied to the direct initiation of gaseous detonations by a blast wave. One-dimensional cylindrical and spherical direct initiation processes in a hydrogen-oxygen mixture are studied with a twenty-four step chemical reaction model. Structures of unsteady reaction zone are clearly resolved. The competition between heat release rate, front curvature, and unsteadiness is investigated. Detailed wave movements in the detonation wave front show that nonlinear waves play an important role in the reacceleration process and are the key to understanding the detonation failure mechanism. The detonation initiation process by implosion shock is then investigated. Shock focusing and shock interactions in the detonation initiation process are examined. Results show a two-shock implosion system due to the interaction between the reflected primary shock and the imploding contact discontinuity. Oblique detonation is studied for the code verification and validation of the two-dimensional CESE solvers. Stabilized detonation structures are resolved and the length of the induction zone is compared with point ignition test data. Implosion with polygonal shock fronts is then explored. Similar to the findings in the one-dimensional results, pressure histories in the focal region show multiple implosions. This Ph.D. study work applies the very accurate and efficient CESE method to study detonation initiation processes. The resultant solvers are state-of-the-art numerical codes that are ready to be applied to time-accurate solutions of detonation initiation processes. This approach provides a new numerical framework for high-fidelity simulations of detonation initiation.

Committee:

John Yu (Advisor); Terrence Conlisk (Committee Member); Xiaodong Sun (Committee Member); Mei Zhuang (Committee Member)

Subjects:

Mechanical Engineering

Keywords:

CESE;Detonation;Initiation;CFD;Finite-rate;Multiple-step

Wilhite, Jarred MInvestigation of Various Novel Air-Breathing Propulsion Systems
MS, University of Cincinnati, 2016, Engineering and Applied Science: Aerospace Engineering
The current research investigates the operation and performance of various air-breathing propulsion systems, which are capable of utilizing different types of fuel. This study first focuses on a modular RDE configuration, which was mainly studied to determine which conditions yield stable, continuous rotating detonation for an ethylene-air mixture. The performance of this RDE was analyzed by studying various parameters such as mass flow rate, equivalence ratios, wave speed and cell size. For relatively low mass flow rates near stoichiometric conditions, a rotating detonation wave is observed for an ethylene-RDE, but at speeds less than an ideal detonation wave. The current research also involves investigating the newly designed, Twin Oxidizer Injection Capable (TOXIC) RDE. Mixtures of hydrogen and air were utilized for this configuration, resulting in sustained rotating detonation for various mass flow rates and equivalence ratios. A thrust stand was also developed to observe and further measure the performance of the TOXIC RDE. Further analysis was conducted to accurately model and simulate the response of thrust stand during operation of the RDE. Also included in this research are findings and analysis of a propulsion system capable of operating on the Inverse Brayton Cycle. The feasibility of this novel concept was validated in a previous study to be sufficient for small-scale propulsion systems, namely UAV applications. This type of propulsion system consists of a reorganization of traditional gas turbine engine components, which incorporates expansion before compression. This cycle also requires a heat exchanger to reduce the temperature of the flow entering the compressor downstream. While adding a heat exchanger improves the efficiency of the cycle, it also increases the engine weight, resulting in less endurance for the aircraft. Therefore, this study focuses on the selection and development of a new heat exchanger design that is lightweight, and is capable of transferring significant amounts of heat and improving the efficiency and performance of the propulsion system.

Committee:

Ephraim Gutmark, Ph.D. (Committee Chair); Paul Orkwis, Ph.D. (Committee Member); Mark Turner, Sc.D. (Committee Member)

Subjects:

Aerospace Materials

Keywords:

Rotating Detonation Engine;RDE;Inverse Brayton Cycle

Suchocki, James AlexanderOperational Space and Characterization of a Rotating Detonation Engine Using Hydrogen and Air
Master of Science, The Ohio State University, 2012, Mechanical Engineering
An experimental study was performed on a rotating detonation engine originally designed by Pratt and Whitney’s Seattle Aerosciences Center. The engine was tested with a hydrogen-air mixture in order to determine the range of operation of the device. After an operating region was found with hydrogen-air, additional oxygen was added to the air in order to expand the engine’s range of operability and thrust output. A number of measurements such as the speed of the detonation wave, the steadiness of the detonation wave, the channel pressure, the thrust output, and the fuel and oxidizer mass flows were measured in order to characterize the operation of the engine. In addition to the increased operability with greater oxygen content, the higher oxygen concentration enabled the engine to detonate at high enough air mass flows to contain two detonation waves during operation. The detonation wave activity before, during, and after the transition from one to two detonation waves was analyzed in order to gain a deeper understanding of the transition phenomenon.

Committee:

John Yu, PhD (Advisor); Michael Dunn, PhD (Committee Member); Frederick Schauer, PhD (Committee Member)

Subjects:

Aerospace Engineering; Mechanical Engineering

Keywords:

Rotating Detonation Engine