Reasearch On Injection,atomization And Operating Characteristics Of Two-phase Continuous Rotating Detonation Engine Fueled By Kerosene

Two-phase continuous rotating detonation engine fueled by kerosene has a broad application prospect in propulsion.In this paper,the injection,atomization,the initiating processes and the operating characteristics of engine when the propagation of detonation wave was self-sustaining were studied by theoretical analysis,numerical simulation and experimental research.And the operating characteristics of two-phase CRDE and gasous CRDE were compared.The injection and atomization processes of the injector were studied by experimental investgation combined with numerical simulation.Two kinds of injectors were designed: one is that oxidizer flows through the circular seam in the injector and the other is through the small holes in the injector.When the oxidizer flows through the small holes in the injector,the atomization uniformity and fineness were lower than that the oxygen flow through the circular seam,and there were larger size droplets in the atomization flow-field.The effects of the factors that include kerosene injection pressure,oxidant pressure,the width of circular seam,the position of kerosene injection holes and total temperature of oxidant on the flow characteristic,the atomization flow field,the diameter and velocity of droplets and the mist spray angle were studied for each injector.The contrast and summary on the atomization flow field characteristics of each injector was introduced in detail.The operating characteristics of the hot tube which was used to ignite the two-phase CRDE were studied by experimental investgation combined with numerical simulation.The igniting process in the hot tube with spiral wire was investigated by numerical simulation.The reflection and converge of detonation wave in the hot tube was found that can increase the temperature of detonation wave,and that has contributed to ignite the mixture in the engine.The pressure of detonation wave in the end of hot tube was measured in experiment.The two-phase continuous rotating detonation model engine fueled by kerosene which includes injector,combustion chamber,the exhaust nozzle and supply lines was designed in research.The high frequency pressure was measured by PCB in the firing test of CRDE for oxygen enriched air or oxygen case.The pressure data after FFT processing was used to analysis the typical waveform characteristics and the time/frequency-domain characteristics of the detonation wave.The detonation propagation velocity and pressure amplitude are obtained from the data by FFT.Results show that the model engine works in single-wave mode in oxygen enrich air flow and the model engine works in double-wave mode in pure oxygen flow.The stable position of detonation wave was moving along the axial of engine that caused the steadiness in propagation.The quantitative relationship between detonation rotating velocity and the oxygen/nitrogen ratio in oxidant flow was acquired in experiments.The detonation velocity increased with the rise of oxygen content in oxidant when the equivalent ratio ranges from 0.799 to 0.939.As the equivalent ratio range from 1.050 to 1.222,the detonation velocity was increased linearly with the rise of oxygen content.The ignition process and the rotating detonation wave propagating in the engine was simulated to acquire the detonation velocity,frequency,thrust and impulse of the engine and compare the working characteristics of gas-phase CRDE with two phases CRDE.The height of detonation wave was periodically changed that caused the unsteadiness in propagation.Comparing the degree of ablation in the wall of these two kinds of engines,the two-phase engine surface ablation phenomenon is less serious than the gas-engine because there were some kerosene droplets on the wall of two phase CRDE combined with injection and atomization results.