Fluid Mechanics, 8 Ed
8th Edition
ISBN: 9789385965494
Author: Frank White
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Chapter 7, Problem 7.18P
Air at 20°C and 1 atm flows at 5 m/s past a flat plate. At x = 60 cm and y = 2.95 mm, use the Blasius solution, Table 7.1, to find (a) the velocity u; and (b) the wall shear stress. (c) For extra credit, find a Blasius formula for the shear stress away from the wall.
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A counter flow double pipe heat exchanger is being used to cool hot oil from 320°F to 285°F
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NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.
Determine the rate of heat transfer in the heat exchanger before any fouling occurs.
Correction factor F
1.0
10
0.9
0.8
R=4.0 3.0 2.0.15 1.0 0.8.0.6 0.4 0.2
0.7
0.6
R=
T1-T2
12-11
0.5
12-11
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
(a) One-shell pass and 2, 4, 6, etc. (any multiple of 2), tube passes
P=
T₁-11
The rate of heat transfer in the heat exchanger is
Btu/h.
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Required information
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NOTE: This is a multi-part question. Once an answer is submitted, you will be unable to return to this part.
Air
Oil
80°C
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Chapter 7 Solutions
Fluid Mechanics, 8 Ed
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