Hostname: page-component-77c89778f8-vsgnj Total loading time: 0 Render date: 2024-07-18T19:01:13.837Z Has data issue: false hasContentIssue false

Contracting ducts of finite length

Published online by Cambridge University Press:  07 June 2016

L. G. Whitehead
Affiliation:
Queen Mary College, London
L. Y. Wu
Affiliation:
Queen Mary College, London
M. H. L. Waters
Affiliation:
Queen Mary College, London
Get access

Summmary

A method of design is given for wind tunnel contractions for two-dimensional flow and for flow with axial symmetry. The two-dimensional designs are based on a boundary chosen in the hodograph plane for which the flow is found by the method of images. The three-dimensional method uses the velocity potential and the stream function of the two-dimensional flow as independent variables and the equation for the three-dimensional stream function is solved approximately. The accuracy of the approximate method is checked by comparison with a solution obtained by Southwell's relaxation method.

In both the two and the three-dimensional designs the curved wall is of finite length with parallel sections upstream and downstream. The effects of the parallel parts of the channel on the rise of pressure near the wall at the start of the contraction and on the velocity distribution across the working section can therefore be estimated.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society. 1951

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.)

References

1. Batchelor, G. K. and Shaw, F. S. (1944). A Consideration in the Design of Wind Tunnel Contractions. Australian Report A.C.A.4, 1944.Google Scholar
2. Lighthill, M. J. (1945). A New Method of Two-dimensional Aerodynamic Design. R. & M. 2112, 1945.Google Scholar
3. Cheers, F. (1945). Note on Wind Tunnel Contractions. R. & M. 2137, 1945.Google Scholar
4. Hughes, N. J. S. (1944). Stream Expansion with a Discontinuity in Velocity on the Boundary. R. & M. 1978, 1944.Google Scholar
5. Fox, L. and Southwell, R. V. (1944). On the Flow of a Gas through a Nozzle with Velocities Exceeding the Speed of Sound. Proc. Roy. Soc. A. 183, pp. 3854, 1944.Google Scholar
6. Tsien, H. S. (1943), On the Design of a Contraction Cone for a Wind Tunnel. Journal of the Aeronautical Sciences, Vol. 10, pp. 6870, 1943.CrossRefGoogle Scholar
7. Szczeniowski, B. (1943). Contraction Cone for a Wind Tunnel. Journal of the Aeronautical Sciences, Vol. 10, pp. 311313, 1943.Google Scholar
8. Thwaites, B. (1946). On the Design of Wind Tunnel Contractions. R. & M. 2278, 1946.Google Scholar
9. Milne-Thompson, L. (1950). Theoretical Hydrodynamics (2nd edition) (Chap. XV). Macmillan & Co., 1950.Google Scholar
10. Southwell, R. V. (1946). Relaxation Methods in Theoretical Physics (Chap. 5). Clarendon Press, 1946.Google Scholar