Wind Tunnel Testing

Paraphrased from Ewing, Bixby, and Knacke, [1] some challenges associated with wind tunnel testing include:

• Designing mounts that don't impact the flow
• Need to test above critical Reynolds numbers
• Wind tunnel wall and blocking effects
  • Subsonic testing:
    • Opening-shock measurements: $//<![CDATA[ \begin{array}{l}\frac{a_{model}}{a_{test section}} < = 0.15\end{array} //]]>$
    • Coefficient of drag measurements: $//<![CDATA[ \begin{array}{l}\frac{a_{model}}{a_{test section}} < = 0.10 \rightarrow 0.15\end{array} //]]>$

Here at MIT, we have the 1" x 1" subsonic open wind tunnel and the Wright Brothers Wind Tunnel, which has a 7 X 10-foot elliptical cross-section.

Resources

[1] Ewing, Bixby, and Knacke, Recovery Systems Design Guide