Machine-translated by Google. Questions are authored in English.
Top

Discussion

Horizontal buoyancy in a wind tunnel is a spurious drag caused by

  • A.Heating of the air by the fan
  • B.A streamwise pressure gradient
  • C.The weight of the model
  • D.Vibration of the support system

Answer: B

The tunnel's own wall boundary layers thicken along the test section, contracting the effective area and producing a slight fall in pressure downstream. That gradient pushes the model backwards exactly as buoyancy would, and it must be subtracted from the measured drag. Slightly diverging walls are often used to remove it.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.