Thinking Like an Engineer: An Active Learning Approach (3rd Edition)
3rd Edition
ISBN: 9780133593211
Author: Elizabeth A. Stephan, David R. Bowman, William J. Park, Benjamin L. Sill, Matthew W. Ohland
Publisher: PEARSON
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Textbook Question
Chapter 13, Problem 12RQ
When a fluid flows around an object, it creates a force, called the drag force, that pulls on the object. The coefficient of drag (Cd) is a dimensionless number that describes the relationship between the force created and the fluid and object properties, given as
Where FD is drag force, ρ is the fluid density, and υ is the velocity of the object relative to the fluid. The area of the object the force acts upon is AP, and for spheres is given by the area of a circle. The Reynolds number in this situation is written as
where DP is the diameter of the object the force acts upon. The following chart shows this relationship. The dashed lines show the predicted theories of Stokes and Newton compared to the solid line of actual results.
- a. If the Reynolds number is 500, what is the coefficient of drag?
- b. If the coefficient of drag is 2, what is the Reynolds number?
Ethylene glycol has a dynamic viscosity of 9.13 centipoise and a specific gravity of 1.109.
- c. If the fluid flows around a sphere of diameter 1 centimeter travelling at a velocity of 2.15 centimeters per second, determine the drag force on the particle in units of newtons. (Hint: First determine the Reynolds number.)
- d. If a coefficient of drag of 10 is produced, what is the diameter of the particle? Assume the fluid moving at 1 centimeter per second (Hint: First determine the Reynolds number.)
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Chapter 13 Solutions
Thinking Like an Engineer: An Active Learning Approach (3rd Edition)
Ch. 13.2 - An unknown amount of oxygen, kept in 8 piston-type...Ch. 13.2 - The data shown graphically in the figure describe...Ch. 13.4 - Prob. 3CCCh. 13.4 - Prob. 4CCCh. 13 - Prob. 1ICACh. 13 - Prob. 2ICACh. 13 - Prob. 3ICACh. 13 - Prob. 4ICACh. 13 - Prob. 5ICACh. 13 - Referring to the previous ICA 13-5, Angus is also...
Ch. 13 - Prob. 7ICACh. 13 - The following instructions apply to ICA 13-7 to...Ch. 13 - The following instructions apply to ICA 13-7 to...Ch. 13 - Prob. 10ICACh. 13 - Prob. 11ICACh. 13 - Prob. 12ICACh. 13 - The following instructions apply to ICA 13-10 to...Ch. 13 - Prob. 14ICACh. 13 - Prob. 15ICACh. 13 - Prob. 16ICACh. 13 - Prob. 17ICACh. 13 - Prob. 18ICACh. 13 - Prob. 19ICACh. 13 - Prob. 20ICACh. 13 - Prob. 21ICACh. 13 - As a reminder, the Reynolds number is discussed in...Ch. 13 - As a reminder, the Reynolds number is discussed in...Ch. 13 - Prob. 1RQCh. 13 - Prob. 2RQCh. 13 - 3. An environmental engineer has obtained a...Ch. 13 - 4. A growing field of inquiry that poses both...Ch. 13 - If an object is heated, the temperature of the...Ch. 13 - The Volcanic Explosivity Index (VEI) is based...Ch. 13 - You are an engineer for a plastics manufacturing...Ch. 13 - A Pitot tube is a device used to measure the...Ch. 13 - As part of an electronic music synthesizer you...Ch. 13 - The following data were collected during testing...Ch. 13 - The relationship of the power required by a...Ch. 13 - When a fluid flows around an object, it creates a...
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