The windshield of a car is defrosted by passing hot air at a temperature Ti =...
Homework Answers
Given,
T1 = 40
C = 313 Kelvin
T2 = -10C
= 263 Kelvin
k = 2.06 x 10^(-5)
(thickness)
= 4 x 10^(-3) m
t = 3600 s
Area A = 10500 cm2
Amount of heat that crosses through the area for 1 hour,
Q = [k.A.(T1 - T2).t]/
Putting the values we get,
Q = 973.499 Watts
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The
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Problem
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A cryogenic flui
d is flowing in a
304 SS
pipe.
The pipe is insulated
on its outside surface
with
6
-
mm thick,
evacuated,
aluminum foil/glass mat insulation.
(“Evacuated” means a partial vacuum is drawn on the
insulation to
remove air that would otherwise fill
pores inside the insulation.)
The pipe
inside diameter
is 127 mm; it’s outside diameter is 138 mm.
The
fluid temperature is
-
173
o
C
.
T
he
air temperature
outside the...
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Problem
:
A cryogenic flui
d is flowing in a
304 SS
pipe.
The pipe is insulated
on its outside surface
with
6
-
mm thick,
evacuated,
aluminum foil/glass mat insulation.
(“Evacuated” means a partial vacuum is drawn on the
insulation to
remove air that would otherwise fill
pores inside the insulation.)
The pipe
inside diameter
is 127 mm; it’s outside diameter is 138 mm.
The
fluid temperature is
-
173
o
C
.
T
he
air temperature
outside the...
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