Ten circular fins of uniform cross section, D=15mm, and a length of 75mm, are attached to a 1m2 wall with surface temperature of 375o The fins are made of a material with k=240W/mK. It is exposed to ambient air at 20oC with a convective heat transfer coefficient 75W/m2K. Use the approximation to change a convective tip to an adiabatic tip. Use equations from table 3-3 (p. 177) and equation 3-69 through 3-78 to determine: Individual fin effectiveness. Overall fin effectiveness.

Ten circular fins of uniform cross section, D=15mm, and a length of 75mm, are attached to a 1m2 wall with surface temperature of 375o The fins are made of a material with k=240W/mK. It is exposed to ambient air at 20oC with a convective heat transfer coefficient 75W/m2K. Use the approximation to change a convective tip to an adiabatic tip. Use equations from table 3-3 (p. 177) and equation 3-69 through 3-78 to determine: Individual fin effectiveness. Overall fin effectiveness.

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 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

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3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.
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Ten circular fins of uniform cross section, D=15mm, and a length of 75mm, are attached to a 1m2 wall with surface temperature of 375o The fins are made of a material with k=240W/mK. It is exposed to ambient air at 20oC with a convective heat transfer coefficient 75W/m2K. Use the approximation to change a convective tip to an adiabatic tip. Use equations from table 3-3 (p. 177) and equation 3-69 through 3-78 to determine: Temperature at the end of the pin. Heat transfer from the fin. Fin efficiency. Individual fin effectiveness. Overall fin effectiveness.
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