Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 1, Problem 1.28P
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
(a) What is the rate of heat loss from the steam line?
(b) If the steam is generated in a gas-fired boiler operating at an efficiency of
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Thermal jackets are typically put on cryogenicstorage tanks to minimize the heat transfer gainsfrom the surroundings. Consider a cylindercontainer that is 1.5 m long made from steel (k = 750W/m.K) with an inner diameter of 0.5 m and outerdiameter of 0.7 m. If the liquefied natural gas (LNG)inside the cylinder is maintained at 90 K, ambientconditions are Tamb = 20 °C, h = 7 W/m2.K.
What is the required insulationmaterial to maintain the outer temperature of that jacket of 15 °C? Usethe end of the book and write your assumption with the right value.(Take a maximum allowed jacket thickness of Lins = 7 cm)
Chapter 1 Solutions
Fundamentals of Heat and Mass Transfer
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