Engineering Board Exam Reviewer · Thermodynamics · hard
A pipe is covered with insulation (k = 0.05 W/m· K) with inner radius 5 cm and outer radius 10 cm. If the temperature difference across the insulation is 100 °C, what is the heat loss per meter of pipe length?
- 100.00 W/m
- 104.36 W/m
- 31.42 W/m
- 45.32 W/m
Answer
D. 45.32 W/m
Solution
q = 2π kL T/ (r2/r1) = 2π (0.05)(1)(100)/ 2 = 45.32 W/m.
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