Rotary derivatives of aerodynamic characteristics are used in the study of dynamics and stability of a wing-in-ground(WIG)effect vehicle.Determination of rotary derivatives of WIG vehicle in wind tunnel tests is conne...Rotary derivatives of aerodynamic characteristics are used in the study of dynamics and stability of a wing-in-ground(WIG)effect vehicle.Determination of rotary derivatives of WIG vehicle in wind tunnel tests is connected with the influence of scale effect,model mounting device and proximity to the ground.In present study the method based on the Reynoldsaveraged Navier-Stokes equations solving is used to predict the rotary derivatives of aircraft type WIG vehicle.The results of determination of rotary derivatives of aircraft in wind tunnel are used for method verification.The dependences of aerodynamic coefficients and rotary derivatives of aircraft type WIG vehicle on the ground clearance are studied basing on numerical simulation results.Some recommendations are formulated for the types of dependences of aerodynamic characteristics used for research of aircraft type WIG vehicles lateral stability and dynamics.展开更多
A solution to a multi-point optimization problem of a wing airfoil for a Long Endurance Mars Exploration Flying Vehicle(LEMFEV)under various constraints is considered.Formulated is the problem of multi-point optimizat...A solution to a multi-point optimization problem of a wing airfoil for a Long Endurance Mars Exploration Flying Vehicle(LEMFEV)under various constraints is considered.Formulated is the problem of multi-point optimization of the airfoil shape,based on level flight conditions of LEMFEV,with an additional condition related to flight Reynolds number variation of the LEMFEVwing.This problem formulationmakes possible the airfoil optimization taking into account the studied vehiclewing loading.The airfoil is optimized for a wide range of flight lift coefficients C_(L)and Reynolds’numbers.It has been shown that taking into account the Reynolds’number makes possible quality improvement of the obtained optimization results,which are physically better justified against existing optimization techniques.Computational Fluid Dynamics(CFD)are applied to validate the obtained aerodynamic coefficients.The most popular CFD simulation methods are based on Reynolds averaged Navier-Stocks equations with semi-empirical turbulence models,such as k−εand k−ω.In this regard,investigated is Ansys Fluent ability to predict the airfoils lift and drag coefficients in Martian atmospheric conditions.Experimental data are used to validate the numerical simulation.The flow around NACA0012-34 airfoil with a chord length c~50 mm is simulated at angles of attack ranging−5…15°using different turbulence models.It has been shown that turbulent Prandtl numberσk in turbulence kinetic energy equation significantly influences on the aerodynamic coefficient prediction accuracy.展开更多
文摘Rotary derivatives of aerodynamic characteristics are used in the study of dynamics and stability of a wing-in-ground(WIG)effect vehicle.Determination of rotary derivatives of WIG vehicle in wind tunnel tests is connected with the influence of scale effect,model mounting device and proximity to the ground.In present study the method based on the Reynoldsaveraged Navier-Stokes equations solving is used to predict the rotary derivatives of aircraft type WIG vehicle.The results of determination of rotary derivatives of aircraft in wind tunnel are used for method verification.The dependences of aerodynamic coefficients and rotary derivatives of aircraft type WIG vehicle on the ground clearance are studied basing on numerical simulation results.Some recommendations are formulated for the types of dependences of aerodynamic characteristics used for research of aircraft type WIG vehicles lateral stability and dynamics.
基金supported by the Russian Science Fund under the Agreement No 22–49-02047 from 09.03.2022.
文摘A solution to a multi-point optimization problem of a wing airfoil for a Long Endurance Mars Exploration Flying Vehicle(LEMFEV)under various constraints is considered.Formulated is the problem of multi-point optimization of the airfoil shape,based on level flight conditions of LEMFEV,with an additional condition related to flight Reynolds number variation of the LEMFEVwing.This problem formulationmakes possible the airfoil optimization taking into account the studied vehiclewing loading.The airfoil is optimized for a wide range of flight lift coefficients C_(L)and Reynolds’numbers.It has been shown that taking into account the Reynolds’number makes possible quality improvement of the obtained optimization results,which are physically better justified against existing optimization techniques.Computational Fluid Dynamics(CFD)are applied to validate the obtained aerodynamic coefficients.The most popular CFD simulation methods are based on Reynolds averaged Navier-Stocks equations with semi-empirical turbulence models,such as k−εand k−ω.In this regard,investigated is Ansys Fluent ability to predict the airfoils lift and drag coefficients in Martian atmospheric conditions.Experimental data are used to validate the numerical simulation.The flow around NACA0012-34 airfoil with a chord length c~50 mm is simulated at angles of attack ranging−5…15°using different turbulence models.It has been shown that turbulent Prandtl numberσk in turbulence kinetic energy equation significantly influences on the aerodynamic coefficient prediction accuracy.
