Various configurations of aircraft wing tip devices have been investigated by performing 3D aerodynamics analysis. The wing tip device in this study was derived from the wing tips of a soaring bird, featuring three smoothly blended elements. Each multi-winglet configuration was integrated into a complete wing-tail-body aircraft configuration. Geometry of each of the three elements in the multi-...

We review and extend to the compressible regime an earlier parallelization of an implicit incompressible unstructured Euler code [9], and solve for ow over an M6 wing in subsonic, transonic, and supersonic regimes. While the parallelization philosophy of the compressible case is identical to the incompressible, we focus here on the nonlinear and linear convergence rates, which vary in di erent ...

In these lectures I shall attempt to survey some of the principal recent developments in computational aerodynamics. Prior to 1960 computational methods were hardly used in aerodynamic analysis, although they were already widely used for structural analysis. The NACA 6 series of airfoils had been developed during the forties, using hand computation to perform the Theodorsen method for conformal...

In advance of cryogenic time-resolved PIV measurements in the European Transonic Windtunnel ETW unsteady CFD simulations of the NASA Common Research Model have been carried out. In the observed high Reynolds number and low Mach number flow regime a pressure induced boundary layer separation occurs on the main wing at high angles of attack. In steady RANS simulations the development of the separ...

A full Navier-Stokes solver has been used t o model transonic flow over three airfoil sections. The method uses a two-dimensional, implicit, conservative finite difference scheme for solving the compressible Navier-Stokes equations. Results are presented as prescribed for the Viscous Transonic Airfoil Workshop to held at the AIAA 25th Aerospace Sciences Meeting. "Jones" airfoils have been inves...

1 Robert O. Lawton Distinguished Professor, Department of Mathematics, Fellow AIAA. 2 Post-Doctoral Research Associate, Department of Mathematics. 3 Research Scientist, Structural Acoustics Branch, Aerodynamics, Aerothermodynamics and Acoustics Competency, Member AIAA. 4 Senior Research Scientist, Computational Modeling and Simulation Branch, Aerodynamics, Aerothermodynamics and Acoustics Compe...

The overwing nacelle (OWN) concept refers to aircraft designs where the engine is installed above wing. OWN configuration offers several advantages over conventional underwing (UWN) vehicles, which include improved fuel-burn and propulsive efficiencies due feasibility of ultrahigh-bypass-ratio turbofans, as well reduced noise. However, a nonoptimal design can result in large transonic drag pena...

We prove the existence of a solution of a free boundary problem for the transonic small-disturbance equation. The free boundary is the position of a transonic shock dividing two regions of smooth flow. Assuming inviscid, irrotational flow, as modeled by the transonic small-disturbance equation, the equation is hyperbolic upstream where the flow is supersonic, and elliptic in the downstream subs...

A small transonic wind tunnel was designed, constructed and calibrated in order to provide a tool for the study and demonstration of transonic flow phenomena. The wind tunnel makes use of flow properties following the propagation of a shock wave along a tube in order to create the transonic flow. This is in contrast to conventional transonic facilities which are supplied from a reservoir or com...

The need of a continuous improvement in gas turbine efficiency for propulsion and power generation, as well as the more demanding operating conditions and power control required to these machines, still ask for great efforts in the design and analysis of the high pressure section of the turbo-expander. To get detailed insights and improve the comprehension of the flow physics, a wide experiment...