Abstract
Experimental and numerical investigations have been conducted to analyze the unsteady aerodynamic and flight mechanical behavior of a 53° flying wing configuration representing a generic unmanned combat air vehicle (UCAV). The considered vehicle is named SACCON/DLR-F17 and the here presented results have been collected within an internal project of the German Aerospace Center in collaboration with the NATO task group AVT-201 on “Extended Assessment of Reliable Stability & Control Prediction Methods for NATO Air Vehicles”. Both projects have the aim to conduct studies of an integrated approach to predict the stability and control characteristics for a generic UCAV configuration based on both experimental and numerical investigations. Systematic investigations have been performed to determine the dynamic derivatives for the longitudinal and lateral motion. A comparison between data of experimental wind tunnel investigations and numerical simulations under real flight conditions is given. In wind tunnel tests, performed in the DNW-NWB wind tunnel, the SACCON configuration was studied at a reduced scale of 1:8 and a Mach number of M∞ = 0.15. Forced oscillation motions were performed during these tests to calculate the dynamic derivatives from force and moment data. For the numerical calculations, the same reduced frequencies were applied with the full-scale configuration under real flight conditions using the RANS method DLR-TAU. The planform aerodynamics is governed by complex non-linear flow phenomena due to leading edge vortex flow separation at moderate to high angles of attack. Based on the numerical results, an interpretation of the complex vortex flow is given to understand the unsteady flow phenomena for a variety of roll, pitch, and yawing motions.
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Abbreviations
- b :
-
Span (m)
- c ref :
-
Reference length (m)
- f :
-
Oscillation frequency (Hz)
- p :
-
Roll rate (°/s)
- q :
-
Pitch rate (°/s)
- r :
-
Yaw rate (°/s)
- s :
-
Half span (m)
- U ∞ :
-
Free stream velocity (m/s)
- \(\alpha\) :
-
Angle of attack (°)
- \(\dot{\alpha }\) :
-
Angular velocity of angle of attack (°/s)
- \(\beta\) :
-
Angle of sideslip (°)
- \(\dot{\beta }\) :
-
Angular velocity of angle of sideslip (°/s)
- \(\omega\) :
-
Angular velocity (°/s)
- \(\omega^{*}\) :
-
Reduced frequency (−) 2πf cref/U∞ longitudinal motion 2πf s/U∞ lateral motion
- \(\varPhi\) :
-
Roll angle (°)
- \(\Delta \varPhi\) :
-
Amplitude rolling oscillation
- \(\varPsi\) :
-
Pitch angle (°)
- \(\Delta \varPsi\) :
-
Amplitude pitching oscillation
- Χ :
-
Yaw angle (°)
- ΔΧ :
-
Amplitude yawing oscillation
- C L :
-
Lift coefficient
- C l :
-
Rolling moment coefficient
- C m :
-
Pitching moment coefficient
- C n :
-
Yawing moment coefficient
- C Y :
-
Side force coefficient
- \(C_{Lq} + C_{{L\dot{\alpha }}}\) :
-
Lift due to pitch motion
- \(C_{mq} + C_{{m\dot{\alpha }}}\) :
-
Pitch damping derivative
- C lp :
-
Roll damping derivative
- C np :
-
Yaw moment due to roll motion
- C Yp :
-
Side force due to roll motion
- \(C_{lr} - C_{{l\dot{\beta }}}\) :
-
Roll moment due to yaw motion
- \(C_{nr} - C_{{n\dot{\beta }}}\) :
-
Yaw damping derivative
- \(C_{Yr} - C_{{Y\dot{\beta }}}\) :
-
Side force due to yaw motion
References
Vicroy, D.D., Huber, K.C., Loeser, T., Rohlf, D.: Low-speed dynamic wind tunnel test analysis of a generic 53° swept UCAV configuration with controls. In: 32nd AIAA Applied Aerodynamics Conference, AIAA-2014-2003, Atlanta, GA, June 2014
Cummings, R.M., Schütte, A.: An integrated computational/experimental approach to UCAV stability & control estimation: overview of NATO RTO AVT-161. In: 28th AIAA Applied Aerodynamics Conference, AIAA-2010-4392, Chicago, IL, June 2010
Cummings, R.M., Schütte, A., et al.: Assessment of stability and control prediction methods for NATO air and sea vehicles. RTO Technical Report, AC/323 (AVT-161) TP/440 (2012)
Cummings, R.M., Schütte, A.: The NATO STO task group AVT-201 on ‘Extended Assessment of Stability and Control Prediction Methods for NATO Air Vehicles’. In: 32nd AIAA Applied Aerodynamics Conference, AIAA-2014-2000, Atlanta, GA, June 2014
Schütte, A., Hummel, D., Hitzel, S.: Numerical and experimental analyses of the vortical flow around the SACCON configuration. In: 28th AIAA Applied Aerodynamics Conference, AIAA-2010-4690, Chicago, IL, June 2010
Zimper, D., Hummel, D.: Analysis of the transonic flow around a generic UCAV configuration. In: 32nd AIAA Applied Aerodynamics Conference, AIAA-2014-2266, Atlanta, GA, June 2014
Hitzel, S.M., Zimper, D.: Model scale and “real” flight of generic UCAV and advanced combat aircraft: an industrial perspective. In: 32nd AIAA Applied Aerodynamics Conference, AIAA-2014-2267, Atlanta, GA, June 2014
Zimper, D., Rein, M.: Experimental and numerical analysis of the transonic vortical flow over a generic lambda wing configuration. In: 32nd AIAA Applied Aerodynamics Conference, AIAA-2014-2005, Atlanta, GA, June 2014
Zimper, D.: Aerodynamisches Verhalten einer generischen UCAV Konfiguration. Dissertation, DLR-Forschungsbericht, DLR-FB-2015-42 (2016)
Vicroy, D.D., Loeser, T.D., Schütte, A.: ACCON forced oscillation tests at DNW-NWB and NASA langley 14x22-foot tunnel. In: 28th AIAA Applied Aerodynamics Conference, AIAA-2010-4394, Chicago, IL, June 2010
Hübner, R.: Experimental and numerical investigations of unsteady aerodynamic derivatives for transport aircraft configurations. In: 45th AIAA Aerospace Sciences Meeting and Exhibit, AIAA-2007-1076, Reno, NV, January 2007
Schwithal, J., Rohlf, D., Looye, G., Liersch, C.M.: An innovative route from wind tunnel experiments to flight dynamics analysis for a highly swept flying wing. DLRK Paper, Document ID: 370008 (2015)
Galle, M., Gerhold, T., Evans, J.: Technical documentation of the DLR TAU-Code. DLR-Interner Bericht, DLR-IB 233-97/A43 (1997)
Gerhold, T., Galle, M., Friedrich, O., Evans, J.: Calculation of complex three-dimensional configurations employing the DLR TAU-Code. In: 35th Aerospace Sciences Meeting and Exhibit, AIAA-1997-0167, Reno, NV, January 1997
Allmaras, S.R., Spalart, P.R.: A one-equation turbulence model for aerodynamic flows. In: 30th Aerospace Sciences Meeting and Exhibit, AIAA-1992-0439, January 1992
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Zimper, D., Huber, K.C. Experimental and numerical investigations of unsteady aerodynamic derivatives for a generic lambda wing UCAV configuration. CEAS Aeronaut J 11, 475–485 (2020). https://doi.org/10.1007/s13272-019-00426-w
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DOI: https://doi.org/10.1007/s13272-019-00426-w