In some wind tunnels the test section is perforated to suck out fluid and provide a thin viscous boundary layer. The test section wall in Fig P3.33 contains 1200 holes of 5-mm diameter each per square meter of wall area. The suction velocity through each hole is Vr = 8 m/s, and the test-section entrance velocity is V1 = 35 m/s. Assuming incompressible steady flow of air at 20°C, compute (a) Vo, (b) V2, and (c) Vf, in m/s. Fig. P3.33

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Test section D,=0.8 m Uniform suction D,- 22 m D-2.5 m