Query: yue huang detonation

title: Effects of jet in crossflow on flame acceleration and deflagration to detonation transition in methane oxygen mixture
abstract: The fluidic jet turbulator has been a novel perturbation generator in the pulse detonation engines research field for the past few years. In this paper, an experiment is performed to study the deflagration to detonation transition (DDT) process in a detonation chamber with a reactive transverse methane oxygen mixture jet in crossflow (JICF) The jet injection arrangement is fundamentally investigated, including single jet and various double jets patterns. Corresponding two dimensional direct numerical simulations with a multistep chemical kinetics mechanism are employed for analyzing details in the flow field, and the interaction between the vortex and flame temporal evolution is characterized. Both the experiments and simulations demonstrate that the JICF can distinctly accelerate flame propagation and shorten the DDT time and distance. The vortex stream induced by the jet distorts and wrinkles the flame front resulting in local flame acceleration. Moreover, the double jet patterns enhance flame acceleration more than the single jet injection because of the intrinsic counter rotating vortex pairs and enhanced turbulence intensity.

title: Effects of Transverse Jet Parameters on Flame Propagation and Detonation Transition in Hydrogen Oxygen Argon Mixture
abstract: Two dimensional numerical simulation is performed with the open source program AMROC to study the effects of transverse jets (act as fluidic obstacles within a detonation tube) on the flame acceleration and deflagration to detonation transition (DDT) The slot transverse jets have been studied and compared with conventional solid obstacles in tubes. The jet initial parameters, such as mixture composition, stagnation temperature, pressure, and mass flow rate, are investigated. The results demonstrate that a hydrogen oxygen argon reactive fluidic obstacle leads to the shortest DDT distance and time compared with solid obstacles and fluidic obstacles composed of pure oxygen or argon. The fluidic obstacles can induce more vorticities to accelerate flame propagation. The DDT distance and time decrease with the jet initial temperature, pressure, and mass flow rate rise, while a high jet initial stagnation temperature is counterproductive to shorting DDT distance and time. The local static pressure rise plays an important role in flame acceleration when increasing the initial pressure of the fluidic obstacle. Higher jet pressure and a wider jet induce more compression waves, which can make the initial flame front more unstable and accelerate the flame as well.

title: Ignition energy effect on detonation initiation by single and two successive ignitions
abstract: In order to investigate the influence of two successive ignitions on the detonation initiation characteristics, the processes of detonation initiation by one ignition and two successive ignitions with different ignition energy and ignition time interval were simulated numerically. Stoichiometric propane air mixture was used as the fuel oxidizer. The simulation and analysis results indicated that a detonation wave could not be initiated in the smooth tube by single ignition with the current ignition energy range of no more than 10000J, while a detonation wave was initiated successfully by two successive ignitions with a certain range of ignition time interval, even when the ignition energy of each ignition decreased to 100J. As the ignition energy decreased, the range of ignition time interval in which the detonation wave could be initiated successfully decreased, while the time and distance of detonation initiation increased.

title: Effects of various components fluidic jet on Deflagration to Detonation Transition in Pulse Detonation Engine

title: Unsteady Flow in Rotating Detonation Nozzle

title: Three Dimensional Parallel Simulation of Formation of Spinning Detonation in a Narrow Square Tube
abstract: Four different formation processes of spinning detonation in a narrow square tube are investigated by three dimensional parallel simulations. High resolution simulations are performed with a Riemann solver of the HLLC type, high order, parallel AMR reactive flow code. The simulations clearly show that the detonation structure transforms from rectangular and diagonal modes into spinning mode respectively during the propagation processes. Transverse wave dynamic and periodic oscillation of the front plays a significant role in the spinning detonations' formation.

title: Experimental investigation on noise radiation characteristics of pulse detonation engine driven ejector
abstract: The noise radiation characteristics of multi cycle pulse detonation engine with and without ejector were investigated under different operating frequencies utilizing gasoline as fuel and air as oxidizer. The straight cylindrical ejector with convergent inlet geometry was coaxially installed at different axial locations relative to the exit of the detonation tube. In all the experiments, the equivalence ratios of gasoline air mixture and the fill fraction were 1.2 and 1.0, respectively. The experimental results implied that the addition of ejector could drastically change the far field acoustic performance of pulse detonation engine exit and the peak sound pressure level of noise radiation was a strong function of the ejector axial position. But the peak sound pressure level was not sensitive to the operating frequencies which varied from 10 to 25 Hz. The pulse sound pressure level, however, increased with the increase in operating frequencies. The far field jet noise measurements of the pulse detonation engine ejector system also showed that ejector could decrease the peak sound pressure level of pulse detonation engine. The maximum reduction was approximately 8.5 dB. For the current pulse detonation engine test conditions, an optimum ejector position was found to be a downstream axial placement of x/DPDE 0.5.

title: Study on Effects of Fluidic Obstacles on Flame Acceleration and Deflagration to Detonation Transition

title: A Target Indirect Thrust Measurement Method of Pulse Detonation Engine
abstract: An indirect thrust measurement method based on impulse of a target plate was developed, and a new thrust measurement system (TMS) was successfully designed and constructed. A series of multi cycle experiments on thrust measurement were conducted to investigate the feasibility of this method with the newly built indirect TMS. The thrust measurement of PDE was made at different plate target axial positions and operating frequencies. All the experiments were conducted using gasoline as fuel and air as oxidant. The experimental results implied that the thrust of PDE by using the indirect impulse method was a function of the target plate axial position, and there existed an optimum measurement position for PDE with a diameter of 60 mm. The optimum target plate position located at 3.33. According to the experimental results, the thrusts obtained by using indirect TMS were less than the actual values, and so the observed value of thrust was modified in order to make the thrust more reliable. A relative accurate calibration formula depending on the operating frequency was found.

title: Overview of Current Activities on PDE and Pulse Detonation Propulsion in China