1. Problem 1
(Thermal Conductivity and the Mechanisms of Energy Transport)
Predict the thermal conductivity of methane at 110.4 atm and 1270F by the following
method:
Use Fig.9.2-1. Obtain the necessary critical properties from Appendix E.
Use the Eucken formula to get the thermal conductivity at 1270F and low pressure.
Then apply a pressure correction by using Fig.9.2-1
(Cp, CH4 = 8.35 cal/mol.K)
Problem 2
(Principles of Heat Flow in Fluids)
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Water at 100C flowing in a -in. 16 BWG condenser tube and saturated steam at
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1050C condensing on the outside. hi = 12 kW/m2.0C, ho = 14 kW/m2.0C, km = 120 W/m.0C
1) Calculate the overall heat-transfer coefficient based on both inside and outside
areas ?
2) Calculate the temperatures of the inside and outside surfaces of the tube ?
Problem 3
(Principles of Heat Flow in Fluids)
Aniline is to be cooled from 200 to 1500F in a double-pipe heat exchanger having
a total outside area of 70 ft2. For cooling, a stream of toluene amounting to 8600 lb/h at a
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temperature of 1000F is available. The exchanger consists of 1 -in. Schedule 40 pipe in
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2-in. Schedule 40 pipe. The aniline flow rate is 10000 lb/h.
1) If flow is countercurrent, what are the toluene outlet temperature, the LMTD, and
the overall heat-transfer coefficient ?
2) If flow is parallel, what are they ?
3) If the overall heat-transfer coefficient is 70 Btu/ft2.h.0F, how much aniline can be
cooled ?
(Note: Using Appendix to obtain the necessary data for solution)