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Design and aeroelastic assessment of a forward-swept wing aircraft


Aeroelastic effects strongly influence the design of an aircraft. To be able to assess those effects early on, reliable simulation models representing the global aeroelastic properties of a new design are required. At a conceptual or a pre-design stage, an intelligent parameterization concept allows for limited changes of the configuration while the simulation models are adapted accordingly. In the DLR project Integrated Green Aircraft, the goal was to investigate the impact of technologies for the reduction of fuel consumption on the aeroelastic properties of aircraft. One main aspect was the influence of laminar wing design on divergence, flutter and dynamic loads. As the reference aircraft in the project, the concept of a forward-swept wing aircraft with rear-mounted engines has been analysed. An aeroelastic model has been built up in the project. The model design procedure is based on the DLR in-house tool set MONA (ModGen/NASTRAN). Focus of this design process is the generation of a parameterized structural model, representing the global dynamic properties of the elastic aircraft, but as detailed as reasonable to capture relevant local effects and to result in a feasible structural design. In the article, the aircraft design is presented. The modelling and sizing process for the structure is described. Results of the loads analysis as well as of the aeroelastic stability analyses are discussed.

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  1. Mai, H., Hebler, A.: Aeroelasticity of a laminar wing. In: Proceedings of IFASD 2011—15th International Forum on Aeroelasticity and Structural Dynamics, 26–30 June 2011, Paris, France (2011)

  2. Fehrs, M.: influence of transitional flows at transonic mach numbers on the flutter speed of a laminar airfoil. In: Proceedings IFASD 2013—16th International Forum on Aeroelasticity and Structural Dynamics, 24–27 June 2013, Bristol, UK (2013)

  3. Schmidt, H., Neumann, J., Mai, H.: Analysis of forced response in a wind tunnel based on doublet-lattice method. CEAS Aeronaut. J. 2, 271–277. Springer. doi:10.1007/s13272-011-0017-5 (2011)

  4. Neumann, J., Mai, H.: Gust response: simulation of an aeroelastic experiment by a fluid-structure interaction method. J. Fluid Struct. 38(1), 290–302. Elsevier (2013)

  5. Seitz, A., Kruse, M., Wunderlich, T., Bold, J., Heinrich, L.: The DLR project LamAiR: design of a NLF forward swept wing for short and medium range transport application. In: 29th AIAA Applied Aerodynamics Conference, 27–30, June 2011, Hawaii, USA (2011)

  6. Kruse, M., Wunderlich, T., Heinrich, L.: A conceptual study of a transonic NLF transport aircraft with forward swept wings. In: 30th AIAA Applied Aerodynamics Conference, 25–28, June 2012, New Orleans, USA (2012)

  7. Heinze, W., Österheld, C.M., Horst, P.: Multidisziplinäres Flugzeugentwurfsverfahren PrADO—Programmentwurf und Anwendung im Rahmen von Flugzeug-Konzeptstudien. Jahrbuch der DGLR-Jahrestagung 2001, Hamburg, Germany (2001)

  8. Krone, N.J. Jr.: Divergence elimination with advanced composites. AIAA Paper 75-1009 (1975)

  9. Weisshaar, T.A.: Divergence of forward swept composite wings. J. Aircr. 17, 442–448 (1980)

    Article  Google Scholar 

  10. Weisshaar, T.A.: Aeroelastic tailoring of forward swept composite wings. J. Aircr. 18(8), 669–676 (1981)

    Article  Google Scholar 

  11. Spacht, G.: The forward swept wing: a unique design challenge. AIAA-80-1885. AlAA Aircraft Systems Meeting, August 4–6, 1980/Anaheim, California (1980)

  12. Lottati, I.: Flutter and divergence aeroelastic characteristics for composite forward swept cantilevered wing. J. Aircr. 22(11), 1001–1007 (1985)

  13. Librescu, L., Thangjithamt, S.: Analytical studies on static aeroelastic behavior of forward-swept composite wing structures. J. Aircr. 28(2), 151–157 (1991)

  14. Dillinger, J., Klimmek, T., Abdalla, M.M., Gürdal, Z.: Stiffness optimization of composite wings with aeroelastic constraints. J. Aircr. 50(4), 1159–1168 (2013). doi:10.2514/1.C032084. (ISSN:0021-8669)

    Article  Google Scholar 

  15. Dillinger, J., Abdalla, M.M., Klimmek, T., Gürdal, Z.: Static aeroelastic stiffness optimization and investigation of forward swept composite wings. In: 10th World Congress on Structural and Multidisciplinary Optimization, 19–24 May 2013, Orlando, Florida, USA (2013)

  16. Hodges, D.: Nonlinear Composite Beam Theory. AIAA, Washington, DC (2006)

    Book  Google Scholar 

  17. Patil, M.J., Hodges, D.H., Cesnik, C.E.S.: Nonlinear aeroelasticity and flight dynamics of high-altitude long endurance aircraft. J. Aircr. 38(1), 88–94 (2001)

    Article  Google Scholar 

  18. Carrera, E., Petrolo, M.: Refined one-dimensional formulations for laminated structure analysis. AIAA J. 50(1) (2012)

  19. Petrolo, M.: Advanced 1D structural models for flutter analysis of lifting surfaces. Int J. Aeronaut. Space Sci. 13(2), 199–209 (2012). doi:10.5139/IJASS.2012.13.2.199

    Google Scholar 

  20. Cavagna, L., Ricci, S., Riccobene, L.: A fast tool for structural sizing, aeroelastic analysis and optimization in aircraft conceptual design. In: AIAA 2009-2571. Proceedings of 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. 4–7 May 2009, Palm Springs, California (2009)

  21. Cavagna, L., Ricci, S., Travaglini, L.: NeoCASS: an integrated tool for structural sizing, aeroelastic analysis and MDO at conceptual design level. Prog. Aerosp. Sci. 47(8), 621–635 (2011)

    Article  Google Scholar 

  22. Patil, M.J., Hodges, D.H.: Flight dynamics of highly flexible flying wings. J. Aircr. 43(6), 1790–1798 (2006)

    Article  Google Scholar 

  23. Su, W., Zhang, J., Cesnik, C.E.S.: Correlations between UM/NAST nonlinear aeroelastic simulations and experiments of a cantilever slender wing. In: Proceedings of IFASD 2009—14th International Forum on Aeroelasticity and Structural Dynamics, 21–25 June 2009, Seattle, WA (USA) (2009)

  24. Frediani, A.: The Prandtl wing. In: Torenbeek, E., Deconinck, H. (eds.) VKI lecture series: “Innovative configurations and advanced concepts for future civil transport aircraft”, 6–10 June, 2005, von Karman Institute, ISBN:2-930389-62-1 (2005)

  25. Bradley, M.K., Droney, C.K.: Subsonic ultra green aircraft research: phase I final report. NASA/CR–2011-216847 (2011)

  26. Frota, J.: New aircraft concept research in NACRE—a five-year synthesis (2005–2010). Presentation. In: Aerodays 2011, 30 March–1 April 2011, Madrid, Spain (2011)

  27. Klimmek, T.: Parameterization of topology and geometry for the multidisciplinary optimization of wing structures. In: Proceedings of CEAS 2009—European Air and Space Conference, Manchester, United Kingdom, 26–29 October 2009 (2009)

  28. Klimmek, T.: Parametric set-up of a structural model for FERMAT configuration for aeroelastic and loads analysis. ASD J. 3(2), 31–49 (2014). doi:10.3293/asdj.2014.27

    Google Scholar 

  29. Loads analysis VAMPzero: Accessed 29 May 2014

  30. Krüger, W.R., Cumnuantip, S., Liersch, C.: Multidisciplinary conceptual design of a UCAV configuration. In: Proceedings of AVT-MP173. RTO/AVT Panel Workshop “Virtual Prototyping of Affordable Military Vehicles Using Advanced MDO”, 16–18 May 2011, Sophia, Bulgaria (2011)

  31. Kroll, N., Rossow, C.: Digital-X: DLR’s way towards the virtual aircraft. In: NIA CFD Conference, 6–8. August 2012, Hampton Virginia, USA (2012)

  32. MSC.NASTRAN: Accessed 29 May 2014

  33. ZAERO: Accessed 29 May 2014

  34. Dorbath, F., Nagel, B., Gollnick, V.: A Knowledge based approach for automated modelling of extended wing structures in preliminary aircraft design. In: Proceedings of DLRK 2011, 27–29 September 2011, Bremen, Deutschland (2011)

  35. Krüger, W.R., Klimmek, T., Liepelt, R., Schmidt, H., Waitz, S., Cumnuantip, S.: Design and aeroelastic assessment of a forward swept wing aircraft. In: Proceedings of IFASD 2013—16th International Forum on Aeroelasticity and Structural Dynamics, 24–26 June 2013, Bristol, UK (2013)

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Correspondence to Wolf R. Krüger.

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Krüger, W.R., Klimmek, T., Liepelt, R. et al. Design and aeroelastic assessment of a forward-swept wing aircraft. CEAS Aeronaut J 5, 419–433 (2014).

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  • Forward-swept wings
  • Aeroelastic design
  • Rear-mounted engines
  • Parametric modelling