Transition Measurements on the Natural Laminar Flow Wing at Mach 2

Transition characteristics of a supersonic natural laminar flow wing with a sweep angle of more than 60 deg were measured using hot-film sensors and an infrared camera at Mach 2. The pressure falls very rapidly in the vicinity of the leading edge of the wing, such that crossflow instabilities are reduced. The flow slightly accelerates downstream such that streamwise instabilities are stabilized. Tests were conducted in two wind tunnels to estimate the transition location in flight: a quiet tunnel with a low Reynolds number and a moderately quiet tunnel with variable Reynolds number. As a result, the natural laminar flow effect of the wing was confirmed. The unit Reynolds number had no effect on the transition Reynolds number of the wing. The transition Reynolds number was 8 x 10 5 at the design angle of attack at Mach 2, but there is room for further investigation

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