Loose Leaf for Fundamentals of Aerodynamics
6th Edition
ISBN: 9781259683992
Author: Anderson, John
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 1, Problem 1.20P
Consider the existence of a forward-facing axial aerodynamic force on an airfoil, as discussed in Section 1.16. Can a forward-facing axial force exist on a flat plate at an angle of attack in a flow? Thoroughly explain your answer.
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You are designing an airfoil for a new hobby RC plane. Because of your limited knowledge, you have mistakenly approximated your airfoil as an ellipse with a = 75mm and b = 12mm. Here, “a” is the depth of your wing and “b” is the thickness. Your plane travels through the air at approximately 20mph (8.9m/s). As it does so, skin friction produces a drag-induced heat of 800W on your wind, of length 1m.
Properties of Air: k = 0.025 W/mK, Pr = 0.72, v = 1.847 x 10−5, u = 16.84 x 10−6, p = 1.2 kg/m3, B = 1/Tf (ideal gas), TInfinity = 25oC
a) What is the average temperature of your wing? Assume an ellipse perimeter of approximately 200mm.
You are designing an airfoil for a new hobby RC plane. Because of your limited knowledge, you have mistakenly approximated your airfoil as an ellipse with a = 75mm and b = 12mm. Here, “a” is the depth of your wing and “b” is the thickness. Your plane travels through the air at approximately 20mph (8.9m/s). As it does so, skin friction produces a drag-induced heat of 800W on your wind, of length 1m.
Properties of Air: k = 0.025 W/mK, Pr = 0.72, v = 1.847 x 10−5, u = 16.84 x 10−6, p = 1.2 kg/m3, B = 1/Tf (ideal gas), TInfinity = 25oC
a) What is the Reynold’s number? Hint: “D” is taken to be the thickness for an elliptical crosssection.
b) What is the Nusselt number?
c) What is the convection coefficient?
d) What is the average temperature of your wing? Assume an ellipse perimeter of approximately 200mm.
Chapter 1 Solutions
Loose Leaf for Fundamentals of Aerodynamics
Ch. 1 - For most gases at standard or near standard...Ch. 1 - Starting with Equations (1.7),(1.8), and (1.11),...Ch. 1 - Consider an infinitely thin flat plate of chord c...Ch. 1 - Consider an infinitely thin flat plate with a 1 m...Ch. 1 - Consider an airfoil at 12 angle of attack. The...Ch. 1 - Consider an NACA 2412 airfoil (the meaning of the...Ch. 1 - The drag on the hull of a ship depends in part on...Ch. 1 - The shock waves on a vehicle in supersonic flight...Ch. 1 - Consider two different flows over geometrically...Ch. 1 - Consider a Lear jet flying at a velocity of 250...
Ch. 1 - A U-tube mercury manometer is used to measure the...Ch. 1 - The German Zeppeins of World War I were dirigibles...Ch. 1 - Consider a circular cylinder in a hypersonic flow,...Ch. 1 - Derive Archimedes principle using a body of...Ch. 1 - Consider a light, single-engine, propeller-driven...Ch. 1 - Consider a flat plate at zero angle of attack in a...Ch. 1 - Consider the Space Shuttle during its atmospheric...Ch. 1 - The purpose of this problem is to give you a feel...Ch. 1 - For the design of their gliders in 1900 and 1901,...Ch. 1 - Consider the existence of a forward-facing axial...
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