Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
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Textbook Question
Chapter 9, Problem 9.45P
At the end of its manufacturing process, a silicon wafer of diameter
(a) What is the initial rate of cooling?
(b) How long does it take for the wafer to reach a temperature of 50°C? Comment on how the relative effects of convection and radiation vary with time during the cooling process.
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7: horizontal steel pipe having a diameter of 5 cm is maintained at a temperature of 50◦C in a large room where the air and wall temperature are at 20◦C. The surface emissivity of the steel may be taken as 0.8. Using the data of Table 1-3, calculate the total heat lost by the pipe per unit length.
I need the answer as soon as possible
At the end of its manufacturing
process, a silicon wafer of diameter d=
258 mm , thickness & =1 mm is at an
initial temperature of 325 C and is
allowed to cool in quiescent, ambient
air and large surroundings for which
T =T= 25 C, What is the initial rate
of cooling by convection (kJ/s) from
the Lower surface ONLY (Watts)?
3
Silicon :p= 2330 kg/m , c̟
= 813
J/kg K, k = 87.8 W/m · K.
-6
Air: v
= 32.15×10 m /s, k = 0.0372
W/m· K, a = 46.8 ×10
0.686,
m /s, Pr =
Quiescent air
T
Tsur
Silicon wafer
D, 8, e, T
Select one:
Chapter 9 Solutions
Fundamentals of Heat and Mass Transfer
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