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
The design of wide-range high-efficiency aerodynamic configurations is one of the most important key technologies in the research of near-space hypersonic vehicles.A double-sided intake configuration with different in...The design of wide-range high-efficiency aerodynamic configurations is one of the most important key technologies in the research of near-space hypersonic vehicles.A double-sided intake configuration with different inlets on the upper and lower surfaces is proposed to adapt to widerange flight.Firstly,the double-sided intake configuration’s design method and flight profile are delineated.Secondly,Computational Fluid Dynamics(CFD)numerical simulation based on multi-Graphics Processing Unit(GPU)parallel computing is adopted to evaluate the vehicle’s performance comprehensively,aiming to verify the feasibility of the proposed scheme.This evaluation encompasses a wide-range basic aerodynamic characteristics,inlet performance,and heat flux at critical locations.The results show that the inlets of the designed integration configuration can start up across Mach number 3.5 to 8.The vehicle possesses multi-point cruising capability by flipping the fuselage.Simultaneously,a 180°rotation of the fuselage can significantly decrease the heat accumulation on the lower surface of the vehicle,particularly at the inlet lip,further decreasing the temperature gradient across the vehicle structure.This study has some engineering value for the aerodynamic configuration design of wide-range vehicles.However,further study reveals that the flow phenomena at the intersection of two inlets are complex,posing potential adverse impacts on propulsion efficiency.Therefore,it is imperative to conduct additional research to delve into this matter comprehensively.展开更多
The flow through an axisymmetric supersonic mixed-compression air inlet has been simulated numerically to investigate the effects and the necessity of the three-dimensional(3D)modeling in comparison with the axisymmet...The flow through an axisymmetric supersonic mixed-compression air inlet has been simulated numerically to investigate the effects and the necessity of the three-dimensional(3D)modeling in comparison with the axisymmetric one.For this purpose,a supersonic inlet has been simulated numerically via axisymmetric and 3D CFD solvers,using the steady state Reynolds-averaged Navier-Stokes equations along with the SST k-ωturbulence model,for a free-stream Mach number of 2.0 and at zero degrees angle of attack.The grid for the 3D cases was a 14.4-degree sector,instead of a 360-degree domain one,with rotational periodic boundary condition for the side boundaries.The results show that both static and total pressure distributions match well with the experimental data for both the axisymmetric and the 3D simulations.If the prediction of performance parameters is the main goal of simulations,it seems that the axisymmetric simulation provides adequate accuracy,and the 3D simulation one is not the best choice.The 3D numerical simulation results in an in-depth study on the supersonic inlets,including the shock wave-boundary layer interaction,the location of the terminal normal shock wave,and consequently the separation point.For an axisymmetric supersonic inlet in an axisymmetric flow condition,3D effects are not strong enough to have a significant influence on the inlet performance for all operational conditions.However,it seems that 3D effects play an important role in both critical and supercritical operating conditions during the steady state operation.展开更多
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.
基金co-supported by the Foundation of National Key Laboratory of Science and Technology on Aerodynamic Design and Research,China(No.614220121020114)the Key R&D Projects of Hunan Province,China(No.2023GK2022)。
文摘The design of wide-range high-efficiency aerodynamic configurations is one of the most important key technologies in the research of near-space hypersonic vehicles.A double-sided intake configuration with different inlets on the upper and lower surfaces is proposed to adapt to widerange flight.Firstly,the double-sided intake configuration’s design method and flight profile are delineated.Secondly,Computational Fluid Dynamics(CFD)numerical simulation based on multi-Graphics Processing Unit(GPU)parallel computing is adopted to evaluate the vehicle’s performance comprehensively,aiming to verify the feasibility of the proposed scheme.This evaluation encompasses a wide-range basic aerodynamic characteristics,inlet performance,and heat flux at critical locations.The results show that the inlets of the designed integration configuration can start up across Mach number 3.5 to 8.The vehicle possesses multi-point cruising capability by flipping the fuselage.Simultaneously,a 180°rotation of the fuselage can significantly decrease the heat accumulation on the lower surface of the vehicle,particularly at the inlet lip,further decreasing the temperature gradient across the vehicle structure.This study has some engineering value for the aerodynamic configuration design of wide-range vehicles.However,further study reveals that the flow phenomena at the intersection of two inlets are complex,posing potential adverse impacts on propulsion efficiency.Therefore,it is imperative to conduct additional research to delve into this matter comprehensively.
文摘The flow through an axisymmetric supersonic mixed-compression air inlet has been simulated numerically to investigate the effects and the necessity of the three-dimensional(3D)modeling in comparison with the axisymmetric one.For this purpose,a supersonic inlet has been simulated numerically via axisymmetric and 3D CFD solvers,using the steady state Reynolds-averaged Navier-Stokes equations along with the SST k-ωturbulence model,for a free-stream Mach number of 2.0 and at zero degrees angle of attack.The grid for the 3D cases was a 14.4-degree sector,instead of a 360-degree domain one,with rotational periodic boundary condition for the side boundaries.The results show that both static and total pressure distributions match well with the experimental data for both the axisymmetric and the 3D simulations.If the prediction of performance parameters is the main goal of simulations,it seems that the axisymmetric simulation provides adequate accuracy,and the 3D simulation one is not the best choice.The 3D numerical simulation results in an in-depth study on the supersonic inlets,including the shock wave-boundary layer interaction,the location of the terminal normal shock wave,and consequently the separation point.For an axisymmetric supersonic inlet in an axisymmetric flow condition,3D effects are not strong enough to have a significant influence on the inlet performance for all operational conditions.However,it seems that 3D effects play an important role in both critical and supercritical operating conditions during the steady state operation.
