Pulse Detonation Engine Cycle Research Articles

Flight Demonstration of Pulse Detonation Engine Using Sounding Rocket S-520-31 in Space

A detonation engine system is successfully demonstrated for the first time in space using sounding rocket S-520-31 of the Japan Aerospace Exploration Agency/Institute of Space Astronautical Science. Detailed flight results of an S-shaped pulse detonation engine (PDE) installed in the rocket are presented herein. The flight is conducted to confirm that the PDE and its system operate at scheduled sequences in space, confirm the reproducibility of the PDE cycle, and despin the rocket around its axis. It is confirmed that the PDE operated successfully for 14 cycles in space. The experimental plateau pressure of is of the calculated plateau pressure, which suggests that detonation occurred in 14 cycles. The pressure profiles of the cycles are similar, and the pressure integrals are , confirming the excellent reproducibility of the PDE cycle. A probability statistical approach assuming a Gaussian distribution is applied to determine the average angular acceleration difference between processes of the PDE operation, mixture supply, and oxygen supply. The results suggested that the PDE despun the rocket via the thrust produced via detonation combustion, which is consistent with a quasi-steady-state model with an accuracy of .

Technological advancements in Pulse Detonation Engine Technology in the recent past: A Characterized Report

Pulse Detonation Engine (PDE), is an emerging and promising propulsive technology all over the world in the past few decades. A pulse detonation engine (PDE) is a type of propulsion system that uses detonation waves to combust the fuel and oxidizer mixture. Theoretically, a PDE can be operate from subsonic to hypersonic flight speeds. Pulsed detonation engines offer many advantages over conventional air-breathing engines and are regarded as potential replacements for air-breathing and rocket propulsion systems, for platforms ranging from subsonic unmanned vehicles, long-range transportation, high-speed vehicles, space launchers to space vehicles. This article highlights the operating cycle of PDE, starting with the fuel-oxidizer mixture, combustion and Deflagration to detonation transition (DDT) followed by purging. PDE combustion process, a unique process, leads to consistent and repeatable detonation waves. This pulsed detonation combustion process causes rapid burning of the fuel-oxidizer mixture, which cannot be seen in any other combustion process as it is a thousand times faster than any other mode of combustion. PDE not only holds the capability of running effectively up to Mach 5 but it also changes the technicalities in space propulsion. The present paper is the extension of the previous study which is also a well characterized status report of PDE in different areas. The present study deals with the categorization of the design approach, computations & simulations, flow visualization, DDT & Thrust enhancement, PDRE’s, experimental detonation engines with some of the experience and research undertaken in Punjab Engineering College under the complete supervision and guidance of Prof. Tejinder Kumar Jindal followed by applications of PDE technology.

Thermodynamic Performance of Pulse Detonation Engine: A Technical Report

The pulse detonation engine (PDE) is a new concept that utilizes supersonic detonation waves in the propulsion or producing specific impulse. The performance of PDE has been analysed by experimental and analytical from the last decades. The number of researcher develops different theories, which is continuously increasing the PDE propulsive performance. The thermodynamic efficiency of the cyclic operation is discussed and compare to each other. In the present paper, five different analytical approaches such as ideal Brayton cycle, ideal Humphery Cycle, and ideal PDE cycle along with C-J model and ZND model have been studied. The consideration of assumptions and neglecting loses, the theoretical performance of the pulse detonation engine become higher than the experimental and computational predicted performance. The thermodynamic parameters such as pressure, temperature density, Mach number and detonation wave velocity are theoretically calculated inside the combustion chamber and exit of the tube.

Analysis on Thermal Efficiency of Non-Compressor Type Pulse Detonation Turbine Engines

Endo et al. (2004) applied thermodynamic analysis to a simplified Pulse Detonation Turbine Engine (PDTE) system to estimate ideal performance; the theoretical thermal efficiency of a non-compressor type PDTE system is assumed to be 20% to 30% with an ethylene-oxygen mixture. Several experimental studies were conducted using a test apparatus composed of an automobile turbocharger connected to a single-tube pulse detonation engine (PDE). The results demonstrated that the measured thermal efficiency was 1% to 5%, far lower than the theoretical thermal efficiency. These studies covered the simplest PDTE system, in which the detonation wave from a PDE tube is directly incident to a turbine and can be considered as the lowest PDTE system performance. This study clarifies the reduced thermal efficiency by building a model simulating the inside of a turbine. The relationship between the turbine peripheral velocity and thermal efficiency of a non-compressor type PDTE with an ethylene-oxygen mixture was determined based on the premise of being constant turbine peripheral velocity during one PDE cycle. The PDTE test apparatus with a single-tube PDE connected automobile turbocharger was used to verify this model experimentally. The turbine peripheral velocity was changed by changing the PDTE operating frequency and was applied to the model to obtain the relationship with thermal efficiency. As PDTE operating frequency increased, the thermal efficiency of the model gradually approached the maximum value at a constant peripheral velocity during one PDE cycle as described above. Similar trends were observed in both tests and model predictions of thermal efficiency as a function of PDTE operating frequency i.e. turbine peripheral velocity.

Flame Acceleration Enhancement by Distributed Ignition Points

The investigation is reported of a novel method for promoting flame acceleration leading to detonation initiation in a tube. A common method used to initiate a detonation wave is via flame acceleration in an obstacle-laden tube. Previous studies with fuel‐air mixtures have shown that the measured detonation run-up distance, and corresponding run-up time, is too long for a pulse detonation engine (PDE) application. The objective of the investigation is to enhance the flame acceleration process that leads to deflagration-to-detonation transition by using multipoint ignition. Experiments were performed in a 3.05-m-long, 14-cm inner-diameter tube equipped with a primary igniter mounted centrally on the tube endplate. Equally spaced orifice plates were placed in the first 2 m of the tube. A bank of four circumferentially equally spaced automotive spark plugs are located after each of the first three orifice plates. The firing time of each igniter bank is variable. The results indicate that flame acceleration is augmented early in the tube and maintained to the end. The reduction in the distance required for the flame to accelerate to a velocity on the order of the speed of sound in the combustion products is modest, on the order of 10%. However, the reduction in the time required to reach this velocity is much more pronounced, which has an impact on the PDE cycle frequency. Flame acceleration was further enhanced by replacing the first few orifice plates with perforated plates with the same total flow area, for example, the flame run-up distance was shortened by 30%. However, detonation initiation was not observed over the 3 m length of the tube in stoichiometric propane‐air mixtures.

Investigations of cycle processes in a pulsed detonation engine operating on fuel–air mixtures

Experimental and computational investigations of a pulsed detonation engine (PDE) under cyclic operation, using hydrogen–air and hydrocarbon–air mixtures, are reported. Experimental measurements from a single-tube PDE in cyclic operation include visualizations of deflagration-to-detonation transition (DDT) and blowdown processes, and dynamic pressure measurements. Simulations were performed for two geometry configurations: an ideal tube PDE with a smooth-wall, initially filled with premixed fuel–air mixtures; and a benchmark tube PDE with internal geometry, a valveless air supply, and in situ fuel injection. Comparisons of experimental and computational visualizations in the benchmark tube PDE show good agreement in cycle process time scales. Realistic simulations of all processes of the PDE cycle (fill, DDT, detonation propagation, blowdown, and purge) of a benchmark tube PDE yield important insights into factors influencing performance. Performance metrics of thrust and impulse were estimated by application of a two-step reduced mechanism for fuel–air mixtures (H 2, C 2H 2, C 2H 4, and C 3H 8) and were validated using data from an ideal tube PDE in the literature.

PULSED DETONATION ENGINE PROCESSES: EXPERIMENTS AND SIMULATIONS

Computational and experimental investigations of a pulsed detonation engine (PDE) operating in a cycle using ethylene/air mixtures are reported. Simulations are performed for two geometry configurations, namely, an ideal tube PDE with a smooth wall fueled with premixed C2H4/O2 and a benchmark tube PDE with internal geometry and a valveless air supply fueled with C2H4. Performance estimates of fuel-specific impulse (Ispf) of an ideal tube PDE, obtained using a two-step reduced mechanism for a C2H4/O2 mixture, are in good agreement with existing test measurements from the literature. Realistic simulations of all processes of the PDE cycle (fill, deflagration-to-detonation transition (DDT), detonation propagation, blowdown, and purge) of a benchmark tube PDE yielded important insights into continuous cycle operation. Experimental measurements include DDT visualizations and dynamic pressure measurements. Comparisons of experimental and computational visualizations show good agreement in cycle process timescales. However, run-up distance is underpredicted, indicating a need to improve the flame propagation mechanism. The predicted decrease in the fuel-specific impulse (Ispf) for the benchmark tube when compared to the I spf of an ideal tube may be attributed to nonuniformities in the mixture composition, the pressure drop resulting from internal geometry, and backflow in the benchmark tube due to a compression wave propagating into the upstream geometry.

酸水素ＰＤＥの２次元サイクル解析による性能評価

In the present analysis, the cycle of pulse detonation engine (PDE) operation, such as combustion, exhaust and filling phases, was performed by 2-dimensional calculations. A 2nd-order MacCormack-TVD scheme is used to solve Navier-Stokes equations where a simplified two-step chemical reaction model is introduced. Model PDEs have various tube lengths with a constant cross section, containing an Ar-diluted stoichiometric oxyhydrogen mixture. The performance of PDE was estimated and compared with the result of Endo-Fujiwara theoretical analysis. In the present PDE performance estimation, useful formulas for impulse per unit area that are in good agreement with theoretical analysis are derived. Through the cycle analysis of PDE operation, the thrust density of each Model PDE was also estimated and essential aspects of the PDE cycle were obtained.

Thermodynamic Cycle Analysis of Pulse Detonation Engines

Pulse detonation engines (PDEs) are currently attracting considerable research and development attention because they promise performance improvements over existing airbreathing propulsion devices. Because of their inherently unsteady behavior, it has been difficult to conveniently classify and evaluate them relative to their steady-state counterparts. Consequently, most PDE studies employ unsteady gasdynamic calculations to determine the instantaneous pressures and forces acting on the surfaces of the device and integrate them over a cycle to determine thrust performance. A classical, closed thermodynamic cycle analysis of the PDE that is independent of time is presented. The most important result is the thermal efficiency of the PDE cycle, or the fraction of the heating value of the fuel that is converted to work that can be used to produce thrust. The cycle thermal efficiency is then used to find all of the traditional propulsion performance measures. The benefits of this approach are 1) that the fundamental processes incorporated in PDEs are clarified; 2) that direct, quantitative comparisons with other cycles (e.g., Brayton or Humphrey) are easily made; 3) that the influence of the entire ranges of the main parameters that influence PDE performance are easily explored; 4) that the ideal or upper limit of PDE performance capability is quantitatively established; and 5) that this analysis provides a basic building block for more complex PDE cycles. A comparison of cycle performance is made for ideal and real PDE, Brayton, and Humphrey cycles, utilizing realistic component loss models. The results show that the real PDE cycle has better performance than the real Brayton cycle only for flight Mach numbers less than about 3, or cycle static temperature ratios less than about 3. For flight Mach numbers greater than 3, the real Brayton cycle has better performance, and the real Humphrey cycle is an overoptimistic (and unnecessary) surrogate for the real PDE cycle.

詳細化学反応を含む２次元数値流体力学によるＰＤＥ性能予測

One-dimensional numerical analyses of pulse detonation engine (PDE) have been performed by numerous workers. In one-dimensional codes, however, it is basically difficult to set adequate boundary conditions at exit plane, although PDE performance depends strongly on the boundary conditions. To evaluate the influence of boundary conditions, we performed a two-dimensional analysis for a straight single PDE, flying in an external environment under different fuel/oxidizer equivalence ratios. As a result, the physical processes in one PDE cycle and associated PDE performance are acquired.