Question

(30 pts) Either pipe insulation or radiation shielding will be used to reduce the heat loss from a steam pipe. The pipe is 16 cm in diameter. The pipe temperature

is Tp = 525 K and its emissivity isƐp = 0.9. The safe maximum surface temperature of the insulation or radiation shield is 305 K. Two options to reduce heat loss are available: ) Pipe insulation, 7-cm-thick, with thermal conductivity kins = 0.105 W/m-K (2) A radiation shield, gapped 1-cm from the pipe, with emissivity ɛshield = 0.1. Assume no convection in the shield gap. Draw and label the appropriate thermal circuit for each option Determine the heat loss per meter of pipe for each option, Q/e Recommend which option to choose

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