An overhead 25-m-long, uninsulated industrial steampipe of 100 mm diameter is routed through a buildingwhose walls and air are at 25°C. Pressurized steammaintains a pipe surface temperature of 150°C, and thecoefficient associated with natural convection is h = 10W/m² • K. The surface emissivity is ɛ = 0.8.%3D(a) What is the rate of heat loss from the steam line?(b) If the steam is generated in a gas-fired boiler oper-ating at an efficiency of n, = 0.90 and naturalpriced at C, = $0.01 per MJ, what is the annualcost of heat loss from the line? »gas is

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An overhead 25-m-long, uninsulated industrial steam pipe of 100 mm diameter is routed through a building whose walls and air are at 25°C. Pressurized steam maintains a pipe surface temperature of 150°C, and the coefficient associated with natural convection is h = 10 W/m? · K. The surface emissivity is e = 0.8. (a) What is the rate of heat loss from the steam Jine? (b) If the steam is generated in a gas-fired boiler oper- ating at an efficiency of n = 0.90 and natural priced at C, = $0.01 per MJ, what is the annual cost of heat loss from the line? %3D gas is %3D

An overhead 25-m-long, uninsulated industrial steam pipe of 100 mm diameter is routed through a building whose walls and air are at 25°C. Pressurized steam maintains a pipe surface temperature of 150°C, and the coefficient associated with natural convection is h = 10 W/m? · K. The surface emissivity is e = 0.8. (a) What is the rate of heat loss from the steam Jine? (b) If the steam is generated in a gas-fired boiler oper- ating at an efficiency of n = 0.90 and natural priced at C, = $0.01 per MJ, what is the annual cost of heat loss from the line? %3D gas is %3D

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter17: Energy In Thermal Processes: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 69P: An aluminum rod 0.500 m in length and with a cross-sectional area of 2.50 cm2 is inserted into a...

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An overhead 25 m-long, uninsulated industrial steam pipe of 100 mm diameter is routed through a building whose walls and air are at 25°C. Pressurized steam maintains a pipe surface temperature of 150°C, the coefficient associated with natural convection h= 10 W/m2K and the surface emissivity ℇ = 0.8 What is the rate of heat loss from the steam line? If the steam is generated in a gas-fired boiler operating at an efficiency of ɳf = 0.90 and natural gas fuel is priced at Cg = $0.01 per MJ, what is the annual cost of heat loss from the steam line?
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