Particle image velocimetry experiments and simulations were conducted in this study to clarify the influence of the DBD plasma actuator on the flow over a flat plate. The result shows that the actuator not only effect...Particle image velocimetry experiments and simulations were conducted in this study to clarify the influence of the DBD plasma actuator on the flow over a flat plate. The result shows that the actuator not only effectively leads to a local rise in near-wall velocity, but also efficiently causes a decrease in the displacement thickness of the boundary layer. Actuator-induced vorticity is generated to intensify the energy exchange between the main flow and the boundary layer, and dynamic energy is thus added directly to the low-energy fluid by the actuator. Although the increase in fluid velocity also brings a rise in dynamic energy loss, the energy added by the actuator can cover this to provide growth in the energy of the boundary layer. The plasma actuator presents a better performance when the free-stream velocity is lower.展开更多
The inlet with scavenge duct is an important part of turboprop aircraft engine.This type of inlet normally has a complex shape,of which the design is challenging and directly affects the flow field quality of the engi...The inlet with scavenge duct is an important part of turboprop aircraft engine.This type of inlet normally has a complex shape,of which the design is challenging and directly affects the flow field quality of the engine entrance and thus the engine performance.In this paper,the parametric design method of a turboprop aircraft inlet with scavenge duct is established by extracting and controlling the transition law of the critical characteristic parameters.The inlet’s performance and internal flow characteristics are examined by wind-tunnel experiment and numerical simulation.The results indicate that a flow tendency of winding up on both sides is formed due to the induction of the inlet profile,as well as a vortex pair on the back side of the power output shaft.The vortex pair dominates the pressure distortion index on the Aerodynamic Interface Plane(AIP).In addition,with the increase of freestream angle of attack,the total-pressure recovery coefficient of the inlet increases gradually while the total pressure distortion index decreases slightly.On the basis of the experimental results under different working conditions,the parametric design method proposed in this paper is feasible.展开更多
基金supported by National Natural Science Foundation of China(No.50976026)the Science Fundamental Research Funds for the Central Universities of China(No.HIT.NSRIF.2013092)
文摘Particle image velocimetry experiments and simulations were conducted in this study to clarify the influence of the DBD plasma actuator on the flow over a flat plate. The result shows that the actuator not only effectively leads to a local rise in near-wall velocity, but also efficiently causes a decrease in the displacement thickness of the boundary layer. Actuator-induced vorticity is generated to intensify the energy exchange between the main flow and the boundary layer, and dynamic energy is thus added directly to the low-energy fluid by the actuator. Although the increase in fluid velocity also brings a rise in dynamic energy loss, the energy added by the actuator can cover this to provide growth in the energy of the boundary layer. The plasma actuator presents a better performance when the free-stream velocity is lower.
基金co-supported by the Civil Airplane Technology Development Program,China(No.MJ-2020-F-10)the National Science and Technology Major Project,China(No.HT-J2019-V-0004-0095).
文摘The inlet with scavenge duct is an important part of turboprop aircraft engine.This type of inlet normally has a complex shape,of which the design is challenging and directly affects the flow field quality of the engine entrance and thus the engine performance.In this paper,the parametric design method of a turboprop aircraft inlet with scavenge duct is established by extracting and controlling the transition law of the critical characteristic parameters.The inlet’s performance and internal flow characteristics are examined by wind-tunnel experiment and numerical simulation.The results indicate that a flow tendency of winding up on both sides is formed due to the induction of the inlet profile,as well as a vortex pair on the back side of the power output shaft.The vortex pair dominates the pressure distortion index on the Aerodynamic Interface Plane(AIP).In addition,with the increase of freestream angle of attack,the total-pressure recovery coefficient of the inlet increases gradually while the total pressure distortion index decreases slightly.On the basis of the experimental results under different working conditions,the parametric design method proposed in this paper is feasible.
