A steam pipe is to be insulated by two insulating materials put over each other. For best results

A Better insulation should be put over pipe and better one over it
B Inferior insulation should be put over pipe and better one over it
C Both may be put in any order
D Whether to put inferior OIL over pipe or the better one would depend on steam temperature

Correct Answer: Better insulation should be put over pipe and better one over it

We should select a material which have low heat transfer capacity. So we should select a material which thermal conductivity is low. So that heat will pass through material is minimum. We should use low thermal conductivity material both side because after all we need to decrease the rate of heat transfer.
Bissoy MCQ
#Mechanical Engineering #Heat And Mass Transfer

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