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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Textbook Question
Chapter 1, Problem 1.21P
An electric resistance heater is embedded in a longcylinder of diameter 30 mm. When water with a temperature of 25°C and velocity of 1m/s flows crosswiseover the cylinder, the power per unit length required to maintain the surface at a uniform temperature of 90°Cis 28 kW/m. When air, also at 25°C, but with a velocityof 10m/s is flowing, the power per unit length requiredto maintain the same surface temperature is 400 W/m.Calculate and compare the convection coefficients for the flows of water and air.
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Fundamentals of Heat and Mass Transfer
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