Fox and McDonald's Introduction to Fluid Mechanics
9th Edition
ISBN: 9781118912652
Author: Philip J. Pritchard, John W. Mitchell
Publisher: WILEY
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Textbook Question
Chapter 9, Problem 125P
An antique airplane carries 50 m of external guy wires stretched normal to the direction of motion. The wire diameter is 5 mm. Estimate the maximum power saving that results from an optimum streamlining of the wires at a plane speed of 175 km/hr in standard air at sea level.
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During the 1920s and early 1930s, the NACA obtained wind tunnel data on different airfoils by testing finite wings with an aspect ratio of 6. These data were then “corrected” to obtain infinite-wing airfoil characteristics. Consider such a finite wing with an area and aspect ratio of 1.5 ft 2 and 6, respectively, mounted in a wind tunnel where the test-section flow velocity is 100 ft/s at standard sea-level conditions. When the wing is pitched to α = −2°, no lift is measured. When the wing is pitched to α = 10°, a lift of 17.9 lb is measured. Calculate the lift slope for the airfoil (the infinite wing) if the span effectiveness factor is 0.95
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Chapter 9 Solutions
Fox and McDonald's Introduction to Fluid Mechanics
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