A 50 meter long cast iron pipe with outer diameter of 10 cm passes in an open space of 288 K temperature. The outer surface of the pipe temperature is 423 K and the combined heat transfer coefficient on the outer surface of the pipe is 25 W/m² K. Considering and stating the necessary assumptions determine, (a) The rate of heat loss from the pipe (b) The energy lost per year if the cost of the fuel is 0.52 $/therm ( 1 therm = 105,500 kJ) (c) The thickness of the insulation if 98% of the energy loss is planned to be saved. Consider the conduction coefficient of the insulation is 0.035 W/mK. Tair = 288 K 423 K Steam 50 m Fiberglass insulation

A 50 meter long cast iron pipe with outer diameter of 10 cm passes in an open space of 288 K temperature. The outer surface of the pipe temperature is 423 K and the combined heat transfer coefficient on the outer surface of the pipe is 25 W/m² K. Considering and stating the necessary assumptions determine, (a) The rate of heat loss from the pipe (b) The energy lost per year if the cost of the fuel is 0.52 $/therm ( 1 therm = 105,500 kJ) (c) The thickness of the insulation if 98% of the energy loss is planned to be saved. Consider the conduction coefficient of the insulation is 0.035 W/mK. Tair = 288 K 423 K Steam 50 m Fiberglass insulation

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.21P

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