Question

Consider a rectangular wing mounted in a full-scale wind tunnel. The wing model completely spans the test section so that the flow sees essentially an infinite wing. The wing has a NACA 0009 airfoil section, a chord of 2.0 m, and a span of 5 m. The tunnel is operated at the following test conditions: P = 95,000 N/m2; T =25◦C; V = 70 m/s; and μ = 1.86 × 10^−5 kg/(m s).
a. Determine the operating Reynolds number.
b. Calculate the lift and drag, about the aerodynamic center for an angle of attack of 10 deg. using the most appropriate curve (indicate which curve you used).
c. Assume in the next test, the most appropriate Reynolds number is 6 × 10^6 and the wing has roughness, but the same dimensions, find the following:

i. What velocity is this wing tested at in the wind tunnel?
ii. What is the stalling angle of attack for this airfoil?
iii. What is the angle of attack for zero lift? and 3) what is the lift- curve slope?
iv. Calculate the lift and drag for case c) at the stall angle.

Answer 1

Answer:

Explanation:

Given the parameters ;

P = 95,000 N/m2; T =25◦C; V = 70 m/s; and μ = 1.86 × 10^−5 kg/(m s).

The detailed steps and appropriate calculation is as shown in the attached files.