[1] During a plant visit, it was noticed that a 12-m-long section of a 10-cm-diameter steam pipe is completely exposedto the ambient air. The temperature measurements indicate that the average temperature of the outer surface of thesteam pipe is 75°C when the ambient temperature is 5°C. There are also light winds in the area at 10 km/h. Theemissivity of the outer surface of the pipe is 0.8, and the average temperature of the surfaces surrounding the pipe,including the sky, is estimated to be 0°C. Determine the amount of heat lost from the steam during a 10-h-long workday. Steam is supplied by a gas-fired steam generator that has an efficiency of 80 percent, and the plant pays$1.05/therm of natural gas. If the pipe is insulated and 90 percent of the heat loss is saved, determine the amount ofmoney this facility will save a year as a result of insulating the steam pipes. Assume the plant operates every day of theyear for 10 h. State your assumptions.T= 0°Csurrɛ = 0.875°C10 cmSteam pipe/////5°C10 km/ha.) Amount of heat lost.A. 2.461x105 kJ/dayB. 4.361x105 kJ/dayC. 3.361x105 kJ/dayD. 2.361x106 kJ/dayb.) Money saved.A. $ 965B. $ 985C. $ 1065D. $ 950

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1] During a plant visit, it was noticed that a 12-m-long section of a 10-cm-diameter steam pipe is completely exposed o the ambient air. The temperature measurements indicate that the average temperature of the outer surface of the team pipe is 75°C when the ambient temperature is 5°C. There are also light winds in the area at 10 km/h. The missivity of the outer surface of the pipe is 0.8, and the average temperature of the surfaces surrounding the pipe, ncluding the sky, is estimated to be 0°C. Determine the amount of heat lost from the steam during a 10-h-long work lay. Steam is supplied by a gas-fired steam generator that has an efficiency of 80 percent, and the plant pays 1.05/therm of natural gas. If the pipe is insulated and 90 percent of the heat loss is saved, determine the amount of noney this facility will save a year as a result of insulating the steam pipes. Assume the plant operates every day of the ear for 10 h. State your assumptions. sur ɛ = 0.8 75°C 10 cm Steam pipe ///// 5°C 10 km/h a.) Amount of heat lost. A. 2.461x105 kJ/day B. 4.361x105 kJ/day C. 3.361x106 kJ/day D. 2.361x105 kJ/day b.) Money saved. A. $ 965 B. $ 985 C. $ 1065 D. $ 950

1] During a plant visit, it was noticed that a 12-m-long section of a 10-cm-diameter steam pipe is completely exposed o the ambient air. The temperature measurements indicate that the average temperature of the outer surface of the team pipe is 75°C when the ambient temperature is 5°C. There are also light winds in the area at 10 km/h. The missivity of the outer surface of the pipe is 0.8, and the average temperature of the surfaces surrounding the pipe, ncluding the sky, is estimated to be 0°C. Determine the amount of heat lost from the steam during a 10-h-long work lay. Steam is supplied by a gas-fired steam generator that has an efficiency of 80 percent, and the plant pays 1.05/therm of natural gas. If the pipe is insulated and 90 percent of the heat loss is saved, determine the amount of noney this facility will save a year as a result of insulating the steam pipes. Assume the plant operates every day of the ear for 10 h. State your assumptions. sur ɛ = 0.8 75°C 10 cm Steam pipe ///// 5°C 10 km/h a.) Amount of heat lost. A. 2.461x105 kJ/day B. 4.361x105 kJ/day C. 3.361x106 kJ/day D. 2.361x105 kJ/day b.) Money saved. A. $ 965 B. $ 985 C. $ 1065 D. $ 950

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.4P: An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a...

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