Heat Transfer
A 10 cm dia steam pipe, carrying steam at 180°C, is covered with an insulation (conductivity = 0.6 W/m.°C). It losses heat to the surroundings at 30°C. Assume a heat transfer co-efficient of 0.8 W/m².°C for heat transfer from surface to the surroundings. Neglect wall resistance of the pipe and film resistance of steam. If the insulation thickness is 2 cms, the rate of heat loss from this insulated pipe will be

Greater than that for uninsulated steam pipe
Equal to that of the uninsulated steam pipe
Less than the steam pipe with 5 cms insulation
Less than that of the uninsulated steam pipe

ANSWER DOWNLOAD EXAMIANS APP

Heat Transfer
Finned tube heat exchangers

facilitate very large temperature drop through tube wall
use metal fins of low thermal conductivity
give larger area per tube
are used for smaller heat load

ANSWER DOWNLOAD EXAMIANS APP