TY - GEN
T1 - Experiments on the aerodynamics of a cambered airfoil in ground effect
AU - Ahmed, M. R.
AU - Takasaki, T.
AU - Kohama, Y.
PY - 2006
Y1 - 2006
N2 - The flow characteristics over a NACA4412 airfoil are studied in a low turbulence wind tunnel with moving ground simulation at a Reynolds number of 3.0 × 105 by varying the angle of attack from 0° to 10° and ground clearance of the trailing edge from five percent of chord to hundred percent. The pressure distribution on the airfoil surface was obtained, velocity survey over the surface was performed, wake region was explored, and lift and drag forces were measured. To ensure that the flow is 2-D, PIV measurements were performed. A strong suction effect on the lower surface at an angle of attack of 0° at the smallest ground clearance caused laminar separation well ahead of the trailing edge. Interestingly, for this airfoil, a loss of upper surface suction was recorded as the airfoil approached the ground for all angles of attack. For angles up to 4°, the lift decreased with reducing ground clearance, while for higher angles, it increased due to higher pressure on the lower surface. The drag was higher close to the ground for all angles investigated mainly due to the modification of the lower surface pressure distribution.
AB - The flow characteristics over a NACA4412 airfoil are studied in a low turbulence wind tunnel with moving ground simulation at a Reynolds number of 3.0 × 105 by varying the angle of attack from 0° to 10° and ground clearance of the trailing edge from five percent of chord to hundred percent. The pressure distribution on the airfoil surface was obtained, velocity survey over the surface was performed, wake region was explored, and lift and drag forces were measured. To ensure that the flow is 2-D, PIV measurements were performed. A strong suction effect on the lower surface at an angle of attack of 0° at the smallest ground clearance caused laminar separation well ahead of the trailing edge. Interestingly, for this airfoil, a loss of upper surface suction was recorded as the airfoil approached the ground for all angles of attack. For angles up to 4°, the lift decreased with reducing ground clearance, while for higher angles, it increased due to higher pressure on the lower surface. The drag was higher close to the ground for all angles investigated mainly due to the modification of the lower surface pressure distribution.
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U2 - 10.2514/6.2006-258
DO - 10.2514/6.2006-258
M3 - Conference contribution
AN - SCOPUS:34250716907
SN - 1563478072
SN - 9781563478079
T3 - Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting
SP - 3132
EP - 3148
BT - Collection of Technical Papers - 44th AIAA Aerospace Sciences Meeting
PB - American Institute of Aeronautics and Astronautics Inc.
T2 - 44th AIAA Aerospace Sciences Meeting 2006
Y2 - 9 January 2006 through 12 January 2006
ER -