A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based co...A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based combustible mixture gas. In the code,Young's technique was employed to track the interface between the explosion products and air,and combustible function model was adopted to simulate ignition process. The code was employed to study explosion flow field inside and outside the duct and to obtain peak pressures in different boundary conditions and ignition positions. Numerical results suggest that during the propagation in a duct,for point initiation,the curvature of spherical wave front gradually decreases and evolves into plane wave. Due to the multiple reflections on the duct wall,multi-peak values appear on pressure-time curve,and peak pressure strongly relies on the duct boundary conditions and ignition position. When explosive wave reaches the exit of the duct,explosion products expand outward and forms shock wave in air. Multiple rarefaction waves also occur and propagate upstream along the duct to decrease the pressure in the duct. The results are in agreement with one-dimensional isentropic gas flow theory of the explosion products,and indicate that the ignition model and multi-material interface treatment method are feasible.展开更多
In this study,a numerical study based on Euler equations and coupled with detail chemistry model is used to improve the propulsion performance and stability of the rotating detonation engine.The proposed fuel injectio...In this study,a numerical study based on Euler equations and coupled with detail chemistry model is used to improve the propulsion performance and stability of the rotating detonation engine.The proposed fuel injection called stratified injection functions by suppressing the isobaric combustion process occurring on the contact surface between fuel and detonation products,and thus the proportion of fuel consumed by detonation wave increases from 67%to 95%,leading to more self-pressure gain and lower entropy generation.A pre-mixed hydrogen-oxygen-nitrogen mixture is used as a reactive mixture.The computational results show that the propulsion performance and the operation stability of the engine with stratified injection are both improved,the temperature of the flow field is notably decreased,the specific impulse of the engine is improved by 16.3%,and the average temperature of the engine with stratified injection is reduced by 19.1%.展开更多
基金Project(10572026) supported by the National Natural Science Foundation of China
文摘A two-dimensional multi-material code was indigenously developed to investigate the effects of duct boundary conditions and ignition positions on the propagation law of explosion wave for hydrogen and methane-based combustible mixture gas. In the code,Young's technique was employed to track the interface between the explosion products and air,and combustible function model was adopted to simulate ignition process. The code was employed to study explosion flow field inside and outside the duct and to obtain peak pressures in different boundary conditions and ignition positions. Numerical results suggest that during the propagation in a duct,for point initiation,the curvature of spherical wave front gradually decreases and evolves into plane wave. Due to the multiple reflections on the duct wall,multi-peak values appear on pressure-time curve,and peak pressure strongly relies on the duct boundary conditions and ignition position. When explosive wave reaches the exit of the duct,explosion products expand outward and forms shock wave in air. Multiple rarefaction waves also occur and propagate upstream along the duct to decrease the pressure in the duct. The results are in agreement with one-dimensional isentropic gas flow theory of the explosion products,and indicate that the ignition model and multi-material interface treatment method are feasible.
基金Project supported by the National Natural Science Foundation of China(No.11702329)the Open Project Program of the State Key Laboratory of Aerodynamics of China Aerodynamics Research and Development Center(CARDC)(No.SKLA20180101)+1 种基金the CARDC Fundamental and Frontier Technology Research Fund(No.PJD20180143)the Open Project Program of Rotor Aerodynamics Key Laboratory(No.RAL20180403),China。
文摘In this study,a numerical study based on Euler equations and coupled with detail chemistry model is used to improve the propulsion performance and stability of the rotating detonation engine.The proposed fuel injection called stratified injection functions by suppressing the isobaric combustion process occurring on the contact surface between fuel and detonation products,and thus the proportion of fuel consumed by detonation wave increases from 67%to 95%,leading to more self-pressure gain and lower entropy generation.A pre-mixed hydrogen-oxygen-nitrogen mixture is used as a reactive mixture.The computational results show that the propulsion performance and the operation stability of the engine with stratified injection are both improved,the temperature of the flow field is notably decreased,the specific impulse of the engine is improved by 16.3%,and the average temperature of the engine with stratified injection is reduced by 19.1%.
