FLOW IN THE VICINITY OF THE PLANE OF SYMMETRY OF A DELTA WING WITH A SMALL SWEEP ANGLE IN THE STRONG INTERACTION REGIME

Experiments have been undertaken to characterize the flow field over a delta wing, with an 85° sweep angle, at 12.5° incidence. Application of a laser Doppler anemometer has enabled detailed three-dimensional velocity data to be obtained within the free shear layer, revealing a system of steady co-rotating vortical structures. These sub-vortex structures are associated with low-momentum flow pockets in the separated vortex flow. The structures are found to be dependent on local Reynolds number, and undergo transition to turbulence. The structural features disappear as the sub-vortices are wrapped into the main vortex core. A local three-dimensional Kelvin–Helmholtz-type instability is suggested for the formation of these vortical structures in the free shear layer. This instability has parallels with the cross-flow instability that occurs in three-dimensional boundary layers. Velocity data at high Reynolds numbers have shown that the sub-vortical structures continue to form, consistent with flow visualization results over fighter aircraft at flight Reynolds numbers.

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Theory of desorption induced by electronic transitions. II. The strong interaction regime

The Journal of Chemical Physics ◽

10.1063/1.475015 ◽

1997 ◽

Vol 107 (20) ◽

pp. 8627-8636 ◽

Cited By ~ 9

Author(s):

Tamar Seideman ◽

Hua Guo

Keyword(s):

Strong Interaction ◽

Electronic Transitions ◽

Interaction Regime

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Optimization of Aerodynamic Parameters of Cropped Delta Wing with Fence at Sonic Mach Number

Journal of Computational and Theoretical Nanoscience ◽

10.1166/jctn.2019.7740 ◽

2019 ◽

Vol 16 (2) ◽

pp. 403-409

Author(s):

M. P. Arun ◽

M. Satheesh ◽

Edwin Raja J. Dhas

Keyword(s):

Shock Wave ◽

Boundary Condition ◽

Mach Number ◽

Sound Speed ◽

Delta Wing ◽

Leading Edge ◽

Supersonic Speed ◽

Sweep Angle ◽

Ansys Fluent ◽

Aerodynamic Parameters

Manufacturing and maintaining different aircraft fleet leads to various purposes, which consumes more money as well as man power. Solution to this, nations that are leading in the field of aeronautics are performing much research and development works on new aircraft designs that could do the operations those were done by varied aircrafts. The foremost benefit of this delta wing is, along the huge rearward sweep angle, the wing’s leading edge would not contact the boundary of shock wave. Further, the boundary is produced at the fuselage nose due to the speed of aircraft approaches and also goes beyond the transonic to supersonic speed. Further, rearward sweep angle greatly worse the airspeed: wings under normal condition to leading edge, so permits the aircraft to fly at great transonic, subsonic, or supersonic speed, whereas the over wing speed is kept to minimal range than that of the sound speed. The cropped delta wing with fence has analysed in three cases: Fences at 3/4th distance from the centre, with fences at half distance from the centre and with fences at the centre. Further, the delta wing that cropped is exported to ANSYS FLUENT V14.0 software and analysed by making the boundary condition settings like sonic Mach number of flow over wing along with the angle of attack.

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Propagation of perturbations in the three-dimensional boundary layer on a delta wing in the viscid-inviscid interaction regime

Fluid Dynamics ◽

10.1134/s0015462810030099 ◽

2010 ◽

Vol 45 (3) ◽

pp. 422-433

Author(s):

G. N. Dudin ◽

K. T. M’int

Keyword(s):

Boundary Layer ◽

Delta Wing ◽

Three Dimensional ◽

Dimensional Boundary ◽

Interaction Regime

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3D momentum imaging of molecular dissociation induced by fast, heavy-ion collisions in the strong interaction regime

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/j.nimb.2011.07.015 ◽

2011 ◽

Vol 269 (21) ◽

pp. 2584-2592 ◽

Cited By ~ 1

Author(s):

V. Horvat ◽

R.L. Watson

Keyword(s):

Strong Interaction ◽

Heavy Ion Collisions ◽

Heavy Ion ◽

Molecular Dissociation ◽

Ion Collisions ◽

Interaction Regime ◽

Momentum Imaging

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Experiment on Wingtip Vortices using a Half Deltawing at the Tips

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.b1119.0882s819 ◽

2019 ◽

Vol 8 (2S8) ◽

pp. 1633-1638

Keyword(s):

Delta Wing ◽

Tangential Velocity ◽

Leading Edge ◽

Force Balance ◽

Aviation Industry ◽

Sweep Angle ◽

Wingtip Vortex ◽

Image Velocimetry ◽

Rotating Wing ◽

Naca 0015

The counter rotating wing tip vortices produced by the aircraft continues to be a big concern for the aviation industry and the aircraft manufacturers due to its hazardous effects on the flight safety and aircraft efficiency. The strength of the vortices poses severe problems to the aircraft operations. Manufacturers developed various wingtip devices to alleviate this problem, but still it is not fully understood and solved. In this thesis, the effectiveness of using a half delta wing at the tips is investigated. The flow field over a low aspect ratio NACA 0015 wing fitted with a slender sharp half delta wing with a leading edge sweep angle 700 at a Reynolds number 1.87 ×105 is investigated. Particle image velocimetry is used to quantify the vortex structure and force balance measurements are used to calculate the aerodynamic data of the wing. The peak vorticity, peak tangential velocity are decreased due to the addition of half delta wing. The over-all radius of the wingtip vortex increased showing a diffused vortex due to the addition of the half delta wing. The core circulation is decreased leading to a lower strength vortex. Though the tip device increased the drag, it increases the aerodynamic efficiency through the improvement in L/D.

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