The efficiency of a wind tunnel

Miller, Wm H (Massachusetts Institute of Technology)
naca-tm-65
February 1922


If, by some means, a steady state of motion of a perfect fluid were established in an ideal wind tunnel, there would be no losses, and the motion would persist indefinitely. In the actual tunnel, the function of the motor-fan group is overcome by the total loss of head in the tube due to friction and eddies.

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