Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-27T08:54:14.916Z Has data issue: false hasContentIssue false
  • English
  • Français

Simulation study of wake encounters with straight and deformed vortices

Published online by Cambridge University Press:  20 April 2016

D. Vechtel
D. Vechtel*
Affiliation:
Department of Flight Dynamics and Simulation, DLR German Aerospace Center, Institute of Flight Systems, Braunschweig, Germany
*
dennis.vechtel@dlr.de
Get access Rights & Permissions [Opens in a new window]

Abstract

A simulation study was conducted in order to investigate the influence of vortex deformation on wake encounter characteristics. Wake vortices tend to be strongly deformed during the decay process, depending on the atmospheric conditions in terms of turbulence and thermal stratification. For quantification of the influence of vortex deformation, encounters of an aircraft of the ‘Medium’ category behind a generator aircraft of the ‘Heavy’ category were simulated with straight vortices and with realistically deformed vortices derived from large-eddy simulations. All relevant parameters that influence the encounter characteristics, such as encounter angles and positions, were varied within a wide range. In order to cover all kinds of vortex deformation, encounters with different vortex ages from 16-136 seconds were simulated. Hence, all relevant phases during the vortex decay from nearly straight and wavy vortices to vortex rings were considered.

The parameter variation study revealed that on average the impact on the encountering aircraft is less with deformed vortices than with straight vortices of comparable strength. Especially with vortex rings, the encountering aircraft is exposed to a much smaller impact. However, the results also show a larger aircraft response during encounters with wavy vortices just prior to vortex linking. The maximum aircraft response with wavy vortices is stronger than with straight vortices of comparable strength. Also, the strongest encounters occur under greater encounter angles with deformed vortices than with straight ones.

Keywords

Vortex deformationhazard assessmentencounter simulation
Type
Research Article
Information
The Aeronautical Journal , Volume 120 , Issue 1226 , April 2016 , pp. 651 - 674
Copyright
Copyright © Royal Aeronautical Society 2016 

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

REFERENCES

1. N.N. Procedures for Air Navigation Services, Air traffic management, ICAO Doc, 2007, 4444, (15), pp 6–12.Google Scholar
2. N.N. Data Show That U.S. Wake-turbulence Accidents Are Most Frequent at Low Altitude and During Approach and Landing, Flight safety digest, Flight Safety Foundation, 2002, 21, (3-4), pp 1–47.Google Scholar
3. Hahn, K.-U. and Schwarz, C.W. Wake vortex avoidance versus landing capacity, AIAA Paper 2006-6322, AIAA Guidance, Navigation, and Control Conference, 2006, Keystone, Colorado, US.CrossRefGoogle Scholar
4. Donohue, G.L. and Rutishauser, D.K. The effect of aircraft wake vortex separation on air transportation capacity, 4 FAA/Eurocontrol R&D Conference, 2001, Santa Fe, New Mexico, US.Google Scholar
5. Luckner, R. Modeling and simulation of wake vortex encounters: state-of-the-art and challenges, AIAA Paper 2012-4633, AIAA Modeling and Simulation Technologies Conference, 2012, Minneapolis, Minnesota, US.CrossRefGoogle Scholar
6. Crow, S.C. Stability theory for a pair of trailing vortices, AIAA J, 1970, 8, (12), pp 2172–2179.CrossRefGoogle Scholar
7. Crow, S.C. and Bate, E.R. Lifespan of trailing vortices in a turbulent atmosphere, J Airc, 1976, 13, (7), pp 476–482.CrossRefGoogle Scholar
8. Loucel, R.E. and Crouch, J.D. Flight-simulator study of airplane encounters with perturbed trailing vortices, AIAA Paper 2004-1074, 42nd AIAA Aerospace Sciences Meeting and Exhibit, 2004, Reno, Nevada, US.CrossRefGoogle Scholar
9. Vechtel, D. In-flight simulation of wake encounters using deformed vortices, Aeronautical J, October 2013, 117, (1196), pp 997–1018.CrossRefGoogle Scholar
10. Vechtel, D. Flight simulator study on the influence of vortex curvature on wake encounter hazard using LES wind fields, Aeronautical J, 2012, 116, (1177), pp 287–302.CrossRefGoogle Scholar
11. Bieniek, D. and Luckner, R. Simulation of aircraft encounters with perturbed vortices considering unsteady aerodynamic effects, AIAA Paper 2012-4657, AIAA Atmospheric Flight Mechanics Conference, 2012, Minneapolis, Minnesota, US.CrossRefGoogle Scholar
12. Raab, C. Flugdynamisches Simulations modell A320-ATRA—Validierungsversuche und Bewertung der Modellgüte (English: Flight dynamics simulation model A320-ATRA—validation tests and rating of model accuracy), DLR Internal Report IB 111-2012/43, 2012, Braunschweig, Germany.Google Scholar
13. Hennemann, I. Deformation und Zerfall von Flugzeugwirbelschleppen in turbulenter und stabil geschichteter Atmosphäre (English: deformation and decay of aircraft wake vortices in turbulent and stable stratified atmosphere), Dissertation, Technical University Munich, 2010, Germany.Google Scholar
14. Fischenberg, D. A method to validate wake vortex encounter models from flight test data, ICAS 2010, 27th International Congress of the Aeronautical Sciences, 2010, Nice, France.Google Scholar
15. N.N. manual of criteria for the qualification of flight simulation training devices, ICAO Doc, 2009, 9625, (3).Google Scholar
16. N.N. A320 flight crew operating manual, Part I, System Description, Issue 01 December 2008.Google Scholar
17. N.N. A320/A321 aircraft maintenance manual AMM, Reference DG. AMM AEF, Issue 01, May 2009.Google Scholar
18. Burnham, D. and Hallock, J. Chicago monostatic acoustic vortex sensing system 4, Wake Vortex Decay, National Information Service, 1982, Springfield, Virginia, US.Google Scholar
19. Rosenhead, L. The formation of vortices from a surface of discontinuity, Proceedings Royal Society of London, Ser. A., 1932, 134, pp 170-192.CrossRefGoogle Scholar
20. Fischenberg, D. Bestimmung der Wirbelschleppencharakteristik aus Flugmessdaten (English: determination of wake vortex characteristics from flight test data), German Aerospace Congress, 2002, Stuttgart, Germany.Google Scholar
21. Schwarz, C.W. and Hahn, K.-U. Full-flight simulator study for wake vortex hazard area investigation, Aerospace Science and Technology, 2006, 10, (2), pp 136–143.CrossRefGoogle Scholar
22. Gerz, T. and Schwarz, C. Das DLR-Projekt “Wetter und Fliegen” (English: the DLR project “weather and flying”), DLR Research Report 2012-02, 2012, Oberpfaffenhofen, Germany.Google Scholar
23. Frech, M. et. al. High-resolution weather database for the terminal area of Frankfurt Airport, J Applied Meteorology and Climatology, 2007, 46, (11), pp 1913–1932.CrossRefGoogle Scholar
24. Barrows, T.M. Simplified methods of predicting aircraft rolling moments due to vortex encounters, AIAA Paper 76-61, AIAA 14th Aerospace Sciences Meeting, 1976, Washington, DC, US.CrossRefGoogle Scholar
25. de Bruin, A. WAVENC, wake vortex evolution and wake vortex encounter, Publishable Synthesis Report, National Aerospace Lab., NLR-TR-2000-079, 2000, Amsterdam, The Netherlands.CrossRefGoogle Scholar
26. Jategaonkar, R., Fischenberg, D. and Gruenhagen, W.v. Aerodynamic modelling and system identification from flight data – recent applications at DLR, J Airc, 2004, 41, (4), pp 687.Google Scholar
27. Hahn, K.-U. and Schwarz, C.W. Safe limits for wake vortex penetration, AIAA Paper 2007-6871, AIAA Guidance, Navigation and Control Conference and Exhibit, 2007, Hilton Head, South Carolina, US.CrossRefGoogle Scholar