This article discusses the enhanced lift-drag ratio of a geometrically modified National Advisory Committee for Aeronautics 0012 aerofoil at low Reynolds number 40000. The study involves validating Averaged Navier Stokes Transition Shear Stress Transport model analysis flow around subject with profile angles attack ranging from 0 to 10°. coefficient lift drag increased by 70% an angle 6°. exten...

We present a new mathematical theory explaning the mircale of flight which is fundamentally different from the existing theory by Kutta-ZhukovskyPrandtl formed 100 year ago. The new theory is based a new resolution of d’Alembert’s paradox showing that slightly viscous bluff body flow can be viewed as zero-drag/lift potential flow modified by a specific separation instability into turbulent flow...

Abstract It is known that plunging airfoil can produce both lift and thrust with certain combination of plunging amplitude and frequency. Motivated by our interest in micro air vehicles (MAVs), we utilize a NavierStokes equation solver to investigate the aerodynamics of a flapping airfoil. The roles of the plunging and pitching amplitude and frequency, and Strouhal number are studied. For a sym...

This paper describes and analyzes a series of nearly CFD test cases performed as a contribu tion to the second Drag Prediction Workshop held in association with the AIAA in June Two con gurations are included DLR F wing body and wing body nacelle pylon The ability of CFD to pre dict the drag lift and pitching moment from exper iment including the delta arising from the ad dition of the nacelle ...

edge modifications on the flow and forces on an untapered wing of 50 deg leading-edge sweep, at stream Mach numbers between 0.60 and 1.20. Seven leading-edge profiles were tested, ranging from a drooped extension of 18 per cent of the chord of the basic sharp-nosed section to a round-nosed section with a leading-edge radius of 1.0 per cent of the basic chord. Leading-edge droop was found to inc...

In many industrial equipment such as boilers and heat exchangers, the cylindrical tubes are exposed to the gas- liquid two phase flow. For any immersed body in flow field vortex shedding is created with a frequency that may be constant or variable, according to conditions such as flow rates, geometry of body, and etc. The failure will happen in the equipment, when this frequency is close to...

The US Army Aeroflightdynamics Directorate (AFDD), the French Office National d’Etudes et de Recherches Aérospatiales (ONERA) and the Georgia Institute of Technology (GIT) are working under the United States/France Memorandum of Agreement on Helicopter Aeromechanics to study rotorcraft aeromechanics issues of interest to both nations. As a task under this agreement, a comparative study of the D...

The effects of aerodynamic perturbation forces on the orbital life of low altitude Low Earth Orbit (LEO) satellites are investigated, with a focus on the secular perturbations caused by lift and drag. The secular effects can be divided into the circularization of the orbit for both lift and drag perturbation forces, and the decrease of the orbit semimajor axis for drag perturbation. A study of ...

Abstract With the purpose of investigating effects geometry parameters CFJ (Coflow jet) device on aerodynamic characteristics supercritical bacj airfoil used by a STOL transport, we have carried out computational analysis with different values injection slot size and location under low-speed condition. The results show that lift coefficient decreases gradually decreasing stall angle, when is in...

The classical problem of the fluid mechanics is the problem of a supersonic motion around a thin body was generalized to the case of non-equilibrium gas. The drag and lift force coefficients were founded. It is shown that the drag and lift force coefficients in the acoustically active supersonic flow are both decreased.