Abstract
The influence of the tip-to-tip distance on the mutually induced aerodynamic forces and moments of a pair of wings simulating the coupling of two aircraft into a compound configuration was numerically and experimentally investigated. The geometry consisted of two identical NACA 0021 rectangular wings with square tips. The numerical investigation was performed as a Reynolds-Averaged Navier Stokes Simulation (RANS) using the OpenFOAM® software package. The simulation was validated by wind-tunnel experiments, whereby the wings were equipped with four chordwise rows of pressure taps to measure the wall pressure. Records were made for different wing-tip distances and different angles of attack combinations. The investigation showed that the relative position of the wings has an influence on their aerodynamic forces and moments, which is relevant in the design of compound, high-altitude and long endurance (HALE) aircraft.
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Abbreviations
- b :
-
Wing span
- c :
-
Wing chord length
- \({\overline{c}}\) :
-
Mean aerodynamic chord length
- d :
-
Wing-tip to wing-tip distance alongside \(y_\mathrm {b}\)-axis
- \(\alpha\) :
-
Angle of attack
- \(c_\mathrm {L}\) :
-
Local lift coefficient
- \(c_\mathrm {p}\) :
-
Local pressure coefficient
- s :
-
Semi wing span
- \(y^+\) :
-
Dimensionless wall distance
- \(C_\mathrm {D}\) :
-
Drag coefficient
- \(C_\mathrm {L}\) :
-
Lift coefficient
- \(C_\mathrm {l}\) :
-
Coefficient of rolling moment
- \(C_\mathrm {m}\) :
-
Coefficient of pitching moment
- \(C_\mathrm {n}\) :
-
Coefficient of yawing moment
- \(\nu _{t}\) :
-
Kinematic turbulent, or eddy, viscosity
- \(u_{\infty }\) :
-
Inflow velocity
- \(\varLambda\) :
-
Wing aspect ratio
- CFD:
-
Computational fluid dynamics
- CG:
-
Centre of gravity
- HALE:
-
High-altitude and long endurance
- HAPS:
-
High altitude pseudo satellites
- PIV:
-
Particle image velocimetry
- RANS:
-
Reynolds-averaged navier stokes
- SPIV:
-
Stereoscopic particle image velocimetry
- TRL:
-
Technology readiness level
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This research was performed with internal funding of TU-Berlin.
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Behrens, A., Grund, T., Ebert, C. et al. Investigation of the aerodynamic interaction between two wings in a parallel flight with close lateral proximity. CEAS Aeronaut J 11, 553–563 (2020). https://doi.org/10.1007/s13272-019-00435-9
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DOI: https://doi.org/10.1007/s13272-019-00435-9