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Jet Separation in Conical Nozzles

Published online by Cambridge University Press:  04 July 2016

H. L. G. Sunley  and
V. N. Ferriman
H. L. G. Sunley
Affiliation:
Rocket Department, Power Division, Bristol Siddely Engines Ltd.
V. N. Ferriman
Affiliation:
Rocket Department, Power Division, Bristol Siddely Engines Ltd.
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Extract

The separation or breakaway of over-expanded gas from a nozzle wall plays an important role in the estimation of the thrust from a rocket engine when run at altitudes considerably less than the design. A number of reports have been written on the subject but the agreement of test results has not appeared to be good.

In an effort to clarify the position, the Rocket Department of Bristol Siddeley Engines Ltd. has carried out tests on experimental combustion chambers having static pressure tappings in the nozzle divergent section. These tests have shown that, contrary to some previous suggestions, the pressure at which the gas separates is neither constant nor independent of the nozzle length. The paper, which includes results from other workers, divides the field into separation adjacent to the nozzle exit and also at positions where the area ratio is less than 80 per cent of the exit area ratio.

For the most part, consideration is given to conical nozzles having divergence half angles of 15° to 17°, but comment is made on the effects of divergence and other variables. A tentative suggestion as to the mechanism of separation is also made.

Finally, the effect of separation on the sea-level thrust of a nozzle designed for high altitude Is shown.

Type
Research Article
Information
The Aeronautical Journal , Volume 68 , Issue 648 , December 1964 , pp. 808 - 817
Copyright
Copyright © Royal Aeronautical Society 1964

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References

1.Stodola, A.Steam and Gas Turbine. McGraw-Hill Book Co. Inc., New York, 1927.Google Scholar
2.Scheller, K. and Bierlein, J. A. Some Experiments on Flow Separation in Rocket Nozzles. Journal of the American Rocket Society, January/February 1953.CrossRefGoogle Scholar
3.Summerfield, M., Foster, C. R. and Swan, W. C. Flow Separation in Overexpanded Supersonic Exhaust Nozzles. Heat Transfer and Fluid Mechanics Inst, Los Angeles, California, 1948.Google Scholar
4.Green, L. Flow Separation in Rocket Nozzles. Technical Note. Journal of the American Rocket Society, January/ February 1953.CrossRefGoogle Scholar
5.Campbell, C. E. and Farley, J. M. Performance of Several Conical Convergent-Divergent Rocket Type Exhaust Nozzles. NASA Tech. Note D-467, May 1960.Google Scholar
6.Ahlberg, J. H., Hamilton, S., Migdal, D.and Nilson, E. N. Truncated Perfect Nozzles in Optimum Nozzle Design. Journal of the American Rocket Society, May 1961.CrossRefGoogle Scholar
7.Musial, N. T. and Ward, J. J. Overexpanded Performance of Conical Nozzles with Area Ratios 6 and 9 with and without Supersonic External Flow. NASA Tech. Memo X-83, May 1959.Google Scholar
8.Nozzle Expansion Tests. Project Note 20 Rocket Division, de Havilland Engine Co. Ltd., July 1960.Google Scholar
9.Holder, D. W. and Gadd, G. E. The Interaction between Shock Waves and Boundary Layers and its Relation to Base Pressure in Supersonic Flow. Proceedings of Symposium Held at N.P.L., March/April 1955.Google Scholar
10.Fradenburgh, E. A., Gorton, G. C. and Beke, A. Thrust Characteristics of a Series of Convergent-Divergent Exhaust Nozzles at Subsonic and Supersonic Flight Speeds. NASA Research Memo E.53L23, December 1953.Google Scholar