Qs A wall separated hot water from cold air in order to increase the heat transfer rate a number of fin s are added to air side. The heat transfer coefficient on the water side is 255 W/m K and on the air side is 57 W/m K, the thermal conductivity is 3 W/m.K. The surface area the wall 3 mx 0.6 m and the fin length is 125 cm with thickness of 0.5 cm if the number of fins are 96. determine the rate of heat transfer by adding the fins. Ans: 7484 W

Qs A wall separated hot water from cold air in order to increase the heat transfer rate a number of fin s are added to air side. The heat transfer coefficient on the water side is 255 W/m K and on the air side is 57 W/m K, the thermal conductivity is 3 W/m.K. The surface area the wall 3 mx 0.6 m and the fin length is 125 cm with thickness of 0.5 cm if the number of fins are 96. determine the rate of heat transfer by adding the fins. Ans: 7484 W

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.16P: 3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer...

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Estimate the rate of heat loss per unit length from a 5-cm ID, 6-cm OD steel pipe covered with high-temperature insulation having a thermal conductivity of 0.11 W/(m K) and a thickness of 1.2 cm. Steam flows in the pipe. It has a quality of 99% and is at 150C. The unit thermal resistance at the inner wall is 0.0026(m2K)/W the heat transfer coefficient at the outer surface is 17W/(m2K) and the ambient temperature is 16C.
3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
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A plane wall (0.8 m x 0.6 m) at 10 oC is to be heated by attaching 7-cm-long, 3-mm-diameter pin fins (k=200 W/mK, ρ=5000 kg/m3) to it. nfin=200 fins are to be used in total. Temperature of the surrounding fluid is 100 oC, and the heat transfer coefficient on the surfaces is 35 W/m2K. Total (material + manufacturing) cost of the fins is 850 TL/kg. Fill the table below by neglecting heat transfer from the fin tips. nfin=? a) Fin efficiency b) Fin effectiveness c) Overall fin effectiveness d) Total cost of fins
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