A steam pipe carrying steam at 385 kPa pressure for a distance of 100 m in a chemical plant is not insulated. Estimate the saving in steam cost that would be made per month if this 10 cm steam line were covered with 85% magnesia pipe covering 5 cm thick. Take room temperature to be 24°C, the cost of steam is 1,000 pesos per one tonne. Thermal conductivity of magnesia k = 0.0745 W/m-K, unit convective coefficient of room air, ho = 12 W/m²-K.

A steam pipe carrying steam at 385 kPa pressure for a distance of 100 m in a chemical plant is not insulated. Estimate the saving in steam cost that would be made per month if this 10 cm steam line were covered with 85% magnesia pipe covering 5 cm thick. Take room temperature to be 24°C, the cost of steam is 1,000 pesos per one tonne. Thermal conductivity of magnesia k = 0.0745 W/m-K, unit convective coefficient of room air, ho = 12 W/m²-K.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.28P

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