Study of the Flowfield Near the Angle-of-Attack Sensor of an A320 Aircraft

Abstract

The flowfield near the angle-of-attack sensors of an Airbus A320 aircraft was modeled numerically, simulating low-speed and high-speed cruise conditions. Because of concerns about the effect of a cargo door installation on the performance of these sensors, an imperfection caused by the gap between the door and the fuselage was modeled. Consequently, by comparing the two computational models, the differences in the flowfield could be studied. The main objectives of this study were to correlate the local streamline angle with the airplane geometrical angle of attack and to quantify the effect of such surface imperfections due to the cargo door installation. At this initial phase, the study was limited to zero sideslip flight conditions. Computed results indicate that the angle-of-attack sensor height is on the same order of magnitude as the local boundary-layer thickness, but nearby flow direction is unaffected by the door groove perturbation. The main conclusion therefore is that the cargo door groove has no significant effect on the flow direction near the angle-of-attack sensors and on the local boundary-layer thickness.