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A hot fluid is being conveyed through a long pipe of 4 cm outer diameter and covered with 2 cm thick insulation. It is proposed to reduce the conduction heat loss to the surroundings to one-third of the present rate by further covering with same insulation. Calculate the additional thickness of insulation

A hot fluid is being conveyed through a long pipe of 4 cm outer diameter and covered with 2 cm thick insulation. It is proposed to reduce the conduction heat loss to the surroundings to one-third of the present rate by further covering with same insulation. Calculate the additional thickness of insulation Correct Answer 12 cm

Heat loss with existing insulation = 2 π k l (t 1 – t 2)/log e (r 2/r 1) and heat loss with additional insulation = 2 π k l (t 1 – t 2)/log e (r 2 + x/r 1).

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