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During test-run, air flows at 215 m/s velocity and 25 degree Celsius temperature past a smooth thin model airfoil which can be idealized as a flat plate. If the chord length of the airfoil is 15 cm, find drag per unit width. The relevant physical properties of air are p = 1.82 kg/m3 v = 15.53 * 10 -6 m2/s

During test-run, air flows at 215 m/s velocity and 25 degree Celsius temperature past a smooth thin model airfoil which can be idealized as a flat plate. If the chord length of the airfoil is 15 cm, find drag per unit width. The relevant physical properties of air are p = 1.82 kg/m3 v = 15.53 * 10 -6 m2/s Correct Answer 25.42 N per unit width

Drag force = 2 C f (p U INFINITY/2) (l) (b) = 25.42 N per unit width.

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