Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-26T19:45:36.006Z Has data issue: false hasContentIssue false
  • English
  • Français

Loads and Pressures Due to Underexpanded Jets Impinging on Wedges*

Published online by Cambridge University Press:  07 June 2016

B.L. Hunt
B.L. Hunt*
Affiliation:
Northrop Corporation
Get access

Summary

Loads have been measured on wedges placed symmetrically in supersonic jets of air. The jets were created by a nozzle with a radially divergent exit section having a lip Mach number of 2.2. The underexpansion ratio was varied from 1 to 2.2 and the distance between the nozzle exit section and the wedge apex was varied from 0 to 2 nozzle exit diameters. All wedges had a base width equal to the nozzle exit diameter: their total included apex angles covered the range 30° to 180°. Pressures were measured on the front faces and the bases for three of the wedges, hence enabling individual contributions to the overall force to be evaluated. Overall loads were measured by means of strain-gauged supports for all six wedges. It was found that the overall load coefficient is only weakly dependent on underexpansion ratio and wedge location but depends strongly on wedge angle. The maximum load coefficient recorded corresponded to 73% of the jet momentum. The base pressures contribute up to 59% of the overall load on a 45° wedge but rather less for larger wedge angles.

Type
Research Article
Information
Aeronautical Quarterly , Volume 34 , Issue 2 , May 1983 , pp. 76 - 98
Copyright
Copyright © Royal Aeronautical Society. 1983

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

*

This work was carried out while the author was a member of the Department of Aeronautical Engineering of the University of Bristol

References

1 Lamont, P.J. and Hunt, B.L. The impingement of underexpanded axisymmetric jets on wedges. Jl. Fluid Mech., Vol. 76, 2, pp 307-336, 1976 Google Scholar
2 Kalghatgi, G.T. and Hunt, B.L. The three shock confluence problem for the case of normally impinging, overexpanded jets. Aero. Quart., Vol. 26, pp 117-132, 1975 Google Scholar
3 Kalghatgi, G.T. and Hunt, B.L. The occurrence of stagnation bubbles in supersonic jet impingement flows. Aero. Quart., Vol. 27, pp 169-185, 1976 CrossRefGoogle Scholar
4 Carling, J.C. and Hunt, B.L. The near wall jet of a normally impinging, uniform, axisymmetric supersonic jet. J. Fluid Mech., Vol. 66, pp 159-177, 1974 Google Scholar
5 Lamont, P.J. and Hunt, B.L. The impingement of underexpanded axisymmetric jets on perpendicular and inclined flat plates. Jl. Fluid Mech., Vol. 100, 3, pp 471-511, 1980 Google Scholar
6 Jennions, I.K. and Hunt, B.L. The axisymmetric impingement of air jets on cones. Aero. Quart., Vol. 31, pp 26-41, 1980 Google Scholar
7 Back, L.H. and Cuffel, R.F. Detection of oblique shocks in a conical nozzle with a circular arc throat. AIAA Jl., Vol. 4, pp 2219-2221, 1966 Google Scholar
8 Glister, M.J. and Foreman, T.J. An investigation of loads on wedges placed in supersonic jets. University of Bristol, B.Sc. Thesis, Dept. of Aeronautical Engg., Report 198, 1976 Google Scholar
9 Henderson, L.F. On the confluence of three shock waves in a perfect gas. Aero. Quart., Vol. 15, pp 181-197, 1964 Google Scholar
10 Monk, B. and Weatherill, K. An investigation of loads on wedges placed in supersonic jets. University of Bristol, B.Sc. Thesis, Dept. of Aeronautical Engg., Report No. 235, 1979 Google Scholar