Setting Boundary Conditions For Slotted Throat Wind Tunnels Using Calorically Imperfect Gas Assumptions

Wind-tunnel interference effects on a 70° delta wing

The Aeronautical Journal ◽

10.1017/s0001924000000336 ◽

2004 ◽

Vol 108 (1088) ◽

pp. 505-513 ◽

Cited By ~ 3

Author(s):

M. R. Allan ◽

K. J. Badcock ◽

G. N. Barakos ◽

B. E. Richards

Keyword(s):

Wind Tunnel ◽

Boundary Conditions ◽

Vortex Breakdown ◽

Delta Wing ◽

Reynolds Numbers ◽

Helix Angle ◽

Wind Tunnels ◽

Wall Boundary Conditions ◽

All Solutions ◽

High Reynolds

Abstract This paper considers the effects of both wind-tunnel walls and a downstream support structure, on the aerodynamics of a 70° delta wing. A RANS model of the flow was used with the wind-tunnel walls and supports being modelled with inviscid wall boundary conditions. A consistent discretisation of the domain was employed such that grid dependence effects were consistent in all solutions, thus any differences occurring were due to varying boundary conditions (wall and support locations). Comparing solutions from wind-tunnel simulations and simulations with farfield conditions, it has been shown that the presence of tunnel walls moves the vortex breakdown location upstream. It has also been seen that vortex strength, helix angle, and mean incidence also increase, leading to a more upstream breakdown location in wind-tunnels. The secondary separation line was also observed to move outboards. It was observed that for high Reynolds numbers, with a support downstream of the wing, vortex breakdown can be delayed due to blockage effects providing the vortices do not impinge on the support This was observed to be the case for smaller supports also.

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Highly-Accurate Artificial Boundary Conditions for Unsteady Transonic Flow Problems in Wind Tunnels

Hyperbolic Problems: Theory, Numerics, Applications ◽

10.1007/978-3-0348-8724-3_42 ◽

1999 ◽

pp. 915-924

Author(s):

Ivan L. Sofronov

Keyword(s):

Boundary Conditions ◽

Transonic Flow ◽

Wind Tunnels ◽

Artificial Boundary ◽

Artificial Boundary Conditions ◽

Flow Problems

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Use of the Magnetostatic Analogue In Electromagnetic Lens Engineering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068795 ◽

1970 ◽

Vol 28 ◽

pp. 360-361

Author(s):

John W. Coleman

Keyword(s):

Boundary Conditions ◽

High Performance ◽

Force Fields ◽

Optical Design ◽

Direct Conversion ◽

Design Engineering ◽

Design Data ◽

Scalar Potentials ◽

Geometric Elements ◽

At Will

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.

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