In a heat exchanger, as shown in the accompanying figure, air flows over brass tubes of 1.8-cm 1D and 2.1-cm OD containing steam. The convection heat transfer coefficients on the air and steam sides of the tubes are
(a)
The overall heat transfer coefficient based on the inner tube area.
Answer to Problem 10.1P
Over all heat transfer co-efficient based on inner surface area is
Explanation of Solution
Given information:
Inner diameter of the tube
Outer diameter of the tube
Air flows outside the tubes and steam flows inside the tubes.
Convective heat-transfer coefficients onair side and steam side are
From Appendix 2 (Table 10),
Thermal conductivity of brass
Part a:
Over all hear transfer co-efficient based on inner surface area.
Over all heat transfer co-efficient based on inner surface area is given by (refer to Equation 10.4 in text book)
(b)
Overall heat transfer coefficient based on outer surface area of the tube
Answer to Problem 10.1P
Overall heat transfer coefficient based on outer surface area of the tube is
Explanation of Solution
Overall heat transfer coefficient based on outer surface area of the tube is given by (refer to equation 10.3 in text book)
Overall heat transfer coefficient based on inner surface area is 50.36
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Chapter 10 Solutions
Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)
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