TY - JOUR
T1 - Reducing drag penalty in the three-dimensional supersonic biplane
AU - Yonezawa, M.
AU - Obayashi, S.
PY - 2009/11/1
Y1 - 2009/11/1
N2 - The two-dimensional (2D) supersonic biplane is well known for its shock wave cancellation effect and zero wave drag at supersonic speed. Nonetheless, in a three-dimensional (3D) setting, this favourable shock wave interaction becomes disturbed in the Mach cone regions at the wing tips of the supersonic biplane, which results in a severe drag penalty near the wing tips. However, this can be alleviated by appropriately designing the planform of the biplane. This study was performed to investigate the patterns of the 3D shock wave interaction using computational fluid dynamics by considering the 3D supersonic biplane with different planforms. The drag was shown to become large when the wing has a high sweepback angle, and it became small when the wing has a small taper ratio. However, an excessively low taper ratio could also lead to a drag greater than that of the rectangular supersonic biplane. It was found that the low drag 3D supersonic biplane has a small sweepback angle and an adequate taper ratio, which results in the vertex line becoming almost perpendicular to the freestream. Thus, in the design of the low drag 3D supersonic biplane, it is important to take into consideration the trade-off between the drag reduction at the mid-span section and the drag penalty near the wing tip and the wing root.
AB - The two-dimensional (2D) supersonic biplane is well known for its shock wave cancellation effect and zero wave drag at supersonic speed. Nonetheless, in a three-dimensional (3D) setting, this favourable shock wave interaction becomes disturbed in the Mach cone regions at the wing tips of the supersonic biplane, which results in a severe drag penalty near the wing tips. However, this can be alleviated by appropriately designing the planform of the biplane. This study was performed to investigate the patterns of the 3D shock wave interaction using computational fluid dynamics by considering the 3D supersonic biplane with different planforms. The drag was shown to become large when the wing has a high sweepback angle, and it became small when the wing has a small taper ratio. However, an excessively low taper ratio could also lead to a drag greater than that of the rectangular supersonic biplane. It was found that the low drag 3D supersonic biplane has a small sweepback angle and an adequate taper ratio, which results in the vertex line becoming almost perpendicular to the freestream. Thus, in the design of the low drag 3D supersonic biplane, it is important to take into consideration the trade-off between the drag reduction at the mid-span section and the drag penalty near the wing tip and the wing root.
KW - Computational fluid dynamics
KW - Shock wave
KW - Supersonic biplane
KW - Supersonic flow
KW - Wing
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U2 - 10.1243/09544100JAERO521
DO - 10.1243/09544100JAERO521
M3 - Article
AN - SCOPUS:70450197704
SN - 0954-4100
VL - 223
SP - 891
EP - 899
JO - Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering
JF - Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering
IS - 7
ER -