Download Introduction to Thermodynamics - Exam 3 | ENGR 210 and more Exams Thermodynamics in PDF only on Docsity! ENGR 210 ā Introduction to Thermodynamiesā Exam_3 - 1 Mar 12 ā 50 minutes
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in 720
2 716
3. Ba
wp
āTotal | 7100
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ENGR 210 - Introduction to Thermodynamicsā Exam_3~ 1 Mar 12 ā 50 minutes
Prob 1 (20 pts) An ordinary egg can be approximated as an incompressible fluid, inside an ellipsoid
with a volume of 87.1 cmĀ®. The egg is initially at a uniform temperature of 8.05Ā°C and is dropped
into boiling water at 93.5Ā°C. Taking the properties of the egg to be p=1020 kg/m? and
c=3.321 kJ/(kg-K), determine how much heat is transferred to the egg until the time the average
temperature of the egg rises to 85.32Ā°C. 2 g
Closed Sys. āPropeches Given Qe 2 kd
No work
EE, - BE 7 DE ss
& Ve kT = roto By BR lew? we 3,321 LF
2 oO: = bee mehT= FS āToles kg lk
x [ex.32- 3.06 4
- ka,
= 0.0a88urks + Leseeyy | o/b
= 22,798 kT ā > 228kT
Prob 2 (16 pts) A simple, single pass water heat exchanger is basically a duct of constant diameter
in which a few layers of electric resistors are placed. A small pump, outside of the heat exchanger,
pushes the water through the duct where itis heated. If in steady flow operation the density of water
is 1020.0 kg/m* (u=104.83 kJ/kg; h=104.83 kJ/kg) at the inlet and 951.8 kg/m? (u=313.99 kJ/kg:
h=314.03 kJ/kg) at the exit, determine the percent increase in velocity of water as it flows through
the heat exchanger.
i? =@51,3 KA
Ā°% increase in velocity = | }
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