Detached-Eddy Simulation of the Vortical Flowfield about the VFE-2 DeltaWing

The numerical simulation of the flow around a 65° delta wing configuration with rounded leading edges is presented. For the numerical simulation the Cobalt Code uses a cell-centered unstructured hybrid mesh approach. Several numerical results are presented for the steady RANS equations as well as for DES and DDES hybrid approaches. The simulations are done as part of the NATO RTO/AVT 113 working group focusing on experimental and numerical research on delta wing configurations with rounded leading edges. Within this paper the focus is related to the dual primary vortex flow topology, especially the sensitivity of the flow to angle of attack and Reynolds number effects. Reasonable results are obtained with both steady RANS and SA-DDES simulations. The results are compared and verified by experimental data, including surface pressure and pressure sensitive paint results. The impact of transition is assessed, and recommendations for improving future simulations are made

Static and dynamic numerical simulations of a generic UCAV configuration with and without control devices

A contribution for the assessment of the static and dynamic aerodynamic behavior of a generic UCAV configuration with control devices using CFD methods is given. For the CFD simulations the unstructured grid based DLR TAU-Code and the structured grid based NLR solver ENSOLV are used. The numerical methods are verified by experimental wind tunnel data. The current investigations should provide a contribution to assess the prediction capability of control device effectiveness using CFD methods. The presented computational results for the assessment will be validated by dedicated experimental data. Furthermore, it should support the understanding of the flow physics around the trailing edge control devices of highly swept configurations with a vortex dominated flow field. Design requirements should be able draw by analyzing the interaction between the vortical flow and the control devices. The present work is part of the NATO STO/AVT Task Group AVT-201 on Stability and Control prediction method

Effects of Leading-Edge Radius on Aerodynamic Characteristics of 50º Delta Wings

The study focuses on the effects of the leading-edge radius on the flow over 50º swept delta wing models. Three models were tested, one model having a sharp leading edge and the other two having a semi-circular leading edge of different radius. The vortical flow on and off the surface of the models was investigated using an oil-flow visualization and a Stereo Particle Image Velocimetry (SPIV) technique. The leading-edge radius is shown to affect the size and location of the vortices and also the vortex bursting location over the models. As a result of this, the leadingedge radius also affects the forces and moment acting on a 50o delta wing.Aerospace Engineerin

Flow over 50º Delta Wings with Different Leading-Edge Radii

The experimental study focuses on the effects of the leading-edge radius on the flow over 50º swept delta wing models. Three models were tested, one model has a sharp leading edge and two other have a semi-circular leading edge of different radius. The vortical flow on and off the surface of the models was investigated using an oil-flow visualization and a Stereo Particle Image Velocimetry (SPIV) technique. The leading-edge radius is shown to affect the location, size and strength of the vortices and also the vortex core breakdown location over the models. As a result of this, the forces and moment acting on a 50o delta wing are also affected. The study further shows that the structure of the flow over such a wing is weakly dependent on Reynolds number.Aerospace Engineerin

Modelisation physique des profils sismiques de subsurface : application a la detection de cavites

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc