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PIV measurements in a twin-jet STOVL fountain flow

Published online by Cambridge University Press:  03 February 2016

P. M. Cabrita
Affiliation:
Department of Aerospace, Power and Sensors, Cranfield University, Shrivenham, Wiltshire, UK
A. J. Saddington
Affiliation:
Department of Aerospace, Power and Sensors, Cranfield University, Shrivenham, Wiltshire, UK
K. Knowles
Affiliation:
Department of Aerospace, Power and Sensors, Cranfield University, Shrivenham, Wiltshire, UK

Abstract

Mean velocity and first order turbulence measurements were obtained from a three-dimensional upwash fountain flow generated by the impingement of two compressible axisymmetric turbulent jets onto a normal plane. The jet impingement area and fountain formation regions were examined with data obtained through the use of particle image velocimetry. Seven configurations with different nozzle pressure ratios were considered to ascertain the influence of jet compressibility on the fountain development. Results indicate that the mixing of the fountain is dependent on the nozzle pressure ratio, leading to an increase in the fountain spreading rate with increase in nozzle pressure ratio.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2005 

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References

1. Anderson, S.B.. Jet-powered V/STOL aircraft – lessons learned. International Powered Lift Conference and Exhibit, pages II.1.1-II.1.14, London, UK, 29-31 August 1990.Google Scholar
2. Curtis, P.. A review of the status of ground effect/environment technologies. International Powered Lift Conference and Exhibit, Williamsburg, VA, USA, 5-7 November 2002. Paper no 2002-5985.Google Scholar
3. Skifstad, J.G.. Aerodynamics of jets pertinent to VTOL aircraft. J Aircr, 1970, 7, (3), pp 193204.Google Scholar
4. Barata, J.M.M.. Fountain flows produced by multi-jet impingement on a ground plane. AIAA J Aircr, 30, (1), pp 5056, 1993.Google Scholar
5. Behrouzi, P. and Mcguirk, J.J.. Experimental data for CFD validation of impinging jets in cross-flow with application to ASTOVL flow problems. AGARD Conference Proceedings CP-534, Fluid Dynamics Panel Symposium, Winchester, UK, 19-22 April 1993.Google Scholar
6. Siclari, M.J., Hill, W.G. and Jenkins, R.C.. Stagnation line and upwash formation of two impinging jets. AIAA J, 19, (10), pp 12861293, October 1981.Google Scholar
7. Wohllebe, F.A. and Siclari, M.J.. Fountain and upwash flowfields of multijet arrangements. J Aircr, August 1978, 15, (8), pp 468473.Google Scholar
8. Saripalli, K.R.. Visualization of multijet impingement flow. AIAA J, April 1983, 21, (4), pp 483484.Google Scholar
9. Kibens, V., Saripalli, K.R., Wlezien, R.W. and Kegelman, J.T.. Unsteady features of jets in lift and cruise modes for VTOL aircraft. International Powered Lift Conference and Exhibit, pp 543552, Santa Clara, CA, USA, 7-10 December 1987. Paper no 872359.Google Scholar
10. Cabrita, P.M., Saddington, A.J. and Knowles, K.. Unsteady features of twin-jet STOVL ground effects. International Powered Lift Conference and Exhibit, Williamsburg, VA, USA, 5-7 November 2002. Paper no 2002-6014.Google Scholar
11. Childs, R.E. and Nixon, D.. Turbulence and fluid/acoustic interaction in impinging jets. International Powered Lift Conference and Exhibit, pp 447458, Santa Clara, CA, USA, 7-10 December 1987. Paper no 872345.Google Scholar
12. Hall, G.R. and Rogers, K.H.. Recirculation effects produced by a pair of heated jets impinging on a ground plane. Contractor Report CR-1307, NASA, 1969.Google Scholar
13. Knowles, K., Wilson, M.J. and Bray, D.. Unsteady pressures under impinging jets in cross-flows. AIAA J, 1993, (3112) pp 23742375.Google Scholar
14. Kotansky, D.R. and Glaze, L.W.. The effects of ground wall-jet characteristics on fountain upwash flow formation and development. 14th AIAA Fluid and Plasma Dynamics Conference, Palo Alto, CA, USA, 23-25 June 1981. Paper no 81-1294.Google Scholar
15. Gilbert, B.L.. Turbulence measurements in a radial upwash. AIAA J, January 1989, 27, (1), pp 4451.Google Scholar
16. El-Okda, Y. and Telionis, D.P.. Experimental investigation of twin jet impinging on the ground with and without a free stream. International Powered Lift Conference and Exhibit, Williamsburg, VA, USA, 5-7 November 2002. Paper no 2002-5976.Google Scholar
17. Elavarasan, R., Venkatakrishnan, L., Krothapalli, A. and Lourenço, L.. Supersonic twin impinging jets. 38th Aerospace Sciences Meeting and Exhibit, Reno, NV, USA, 10-13 January 2000. Paper no 2000-0812.Google Scholar
18. Bray, D.. Jets in Cross-flow and Ground Effect. PhD thesis, Cranfield Institute of Technology, Shrivenham, UK, 1992.Google Scholar
19. Westerweel, J.. Fundamentals of digital particle image velocimetry. Measurement Science and Technology, 1997, 8, (12): 13791392.Google Scholar
20. Dring, R.P.. Sizing criteria for laser anemometry particles. J Fluids Engineering, 104, pp 1517, 1982.Google Scholar
21. Saddington, A. J., Lawson, N. J. and Knowles, K.. An experimental and numerical investigation of under-expanded turbulent jets. Aeronau J, March 2004, 108, (1081), pp 145152.Google Scholar
22. Ross, C.B., Lourenço, L. and Krothapalli, A.. Particle image velocimetry measurements in a shock-containing supersonic flow. 32nd AIAA Aerospace Sciences Meeting and Exhibit, Reno, NV, USA, 10-13 January 1994. Paper no. 94-0047.Google Scholar
23. Keane, R.D. and Adrian, R.J.. Optimization of particle image velocimeters. Measurement Science and Technology, November 1990, 1, (11), pp 12021215.Google Scholar
24. Donaldson, C.D. and Snedeker, R.S.. A Study of free jet impingement. Part 1. Mean properties of free and impinging jets. J Fluid Mechanics, 1971, 45, (2), pp 281319.Google Scholar
25. Krothapalli, A., Rajakuperan, E., Alvi, F.S. and Lourenço, L.. Flow field and noise characteristics of a supersonic impinging jet. J Fluid Mechanics, August 1999, 392, pp 155181.Google Scholar
26. Abbott, W.A. and White, D.R.. The effect of nozzle pressure ratio on the fountain formed between two impinging jets. Technical Memorandum P1166, RAE, 1989.Google Scholar