Experimental determination of the free-stream disturbance field in a short-duration supersonic wind tunnel

AbstractA constant temperature hot-wire anemometer enabling automatic rapid scanning of the wire overheat was built to perform free stream disturbance measurements in the shock wind tunnel of the Institute for Aerodynamics and Gasdynamics at Stuttgart University. It is shown that such a system brings real advantages in terms of testing time. The change of bridge dynamic behaviour with wire temperature is taken into account by measuring the bridge frequency response with a very fast electrical test and postprocessing the data. The method of operation is validated in a supersonic suck down wind tunnel and a comparison with a commercial constant temperature bridge shows good agreement. Results of free stream disturbance measurements in a short duration supersonic wind tunnel of 120ms testing time are presented.

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Experimental determination of the effects of steep front-short duration surges on 25 kVA pole mounted distribution transformers

IEEE Transactions on Power Delivery ◽

10.1109/61.25592 ◽

1989 ◽

Vol 4 (2) ◽

pp. 1103-1110 ◽

Cited By ~ 2

Author(s):

C.H. Eichler ◽

J.R. Legro ◽

P.R. Barnes

Keyword(s):

Experimental Determination ◽

Short Duration ◽

Distribution Transformers

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Experimental Determination of the Effects of Steep Front-Short Duration Surges on 25 KVA Pole Mounted Distribution Transformers

IEEE Power Engineering Review ◽

10.1109/mper.1989.4310609 ◽

1989 ◽

Vol 9 (4) ◽

pp. 70-71

Author(s):

Charles H. Eichler ◽

James R. Legro ◽

Paul R. Barnes

Keyword(s):

Experimental Determination ◽

Short Duration ◽

Distribution Transformers

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Structure of Acoustic Radiation from an Artificially Excited Supersonic Boundary Layer

International Journal of Aeroacoustics ◽

10.1260/1475472054771402 ◽

2005 ◽

Vol 4 (3) ◽

pp. 353-362

Author(s):

Nickolay V. Semionov ◽

Alexander D. Kosinov

Keyword(s):

Boundary Layer ◽

Free Stream ◽

Acoustic Radiation ◽

Supersonic Boundary Layer ◽

Local Source ◽

Hot Wire ◽

Supersonic Wind Tunnel ◽

Local Disturbance ◽

Wave Characteristics ◽

Disturbance Field

An experimental study of the controlled disturbance field, introduced into the free stream with the help of the local source of disturbances, was carried out. The controlled disturbances were excited in the supersonic boundary layer by using a local disturbance generator designed based on the amount of discharge in the chamber in the plate. This process was accompanied by radiation of controlled disturbances into the free stream. This radiation from the system “discharge-boundary layer” was used as controlled disturbances in the free stream. The acoustic nature of the radiation was obtained. The levels, wave characteristics and modes of the artificial fluctuations have been obtained by hot-wire measurements in the free stream of the supersonic wind tunnel at a Mach number of 2.

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Low-Turbulence High-Speed Wind Tunnel for the Determination of Cascade Shock Losses

Volume 1B: Gas Turbines ◽

10.1115/79-gt-129 ◽

1979 ◽

Author(s):

J. A. Slovisky ◽

W. B. Roberts ◽

D. M. Sandercock

Keyword(s):

Wind Tunnel ◽

High Speed ◽

Axial Compressor ◽

Pressure Probe ◽

Supersonic Wind Tunnel ◽

Smoke Flow ◽

Contraction Ratio ◽

Curved Shock Waves ◽

Visualization Techniques

A low turbulence high-speed wind tunnel, using anti-turbulence screening and a 100:1 contraction ratio, has been found suitable for high-speed smoke flow visualization. The location and strength of normal, oblique, and curved shock waves generated by transonic or supersonic wind tunnel flow over airfoils or through axial compressor cascades is determined by combined shadowgraph and smokelines visualization techniques without the interference effects caused by intrusive probes. The Reynolds number based on chord varied between 50,000 and 106. Preliminary results are compared with the relevant theory and data gathered using a total pressure probe.

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Experimental Determination of Oscillatory Lift and Moment Distributions on Fully Submerged Flexible Hydrofoils

Journal of Ship Research ◽

10.5957/jsr.1963.7.4.24 ◽

1963 ◽

Vol 7 (04) ◽

pp. 24-41

Author(s):

Guido E. Ransleben ◽

H. Norman Abramson

Keyword(s):

Steady State ◽

Wind Tunnel ◽

Aspect Ratio ◽

Experimental Determination ◽

Theoretical Predictions ◽

Wind Tunnel Data

Measured span wise distributions of steady state and oscillatory lift and moment on fully submerged cantilever hydrofoils are presented. The hydrofoils were of aspect ratio 5 rectangular platform, and were towed at speeds sufficiently low to avoid cavitation. The data are compared with theoretical predictions and wind-tunnel data previously obtained at higher values of reduced velocity.

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