The average heat transfer coefficent for airflow over an odd shaped body is to be determined by mass transfer measurements and using the Chilton-Colburn analogy btwn heat and mass transfer. The experiemnt is conducted by blowing dry air at 1 atm at a free-stream velocity of 2 m/s over a body covered with a layer of naphthalene. The surface area of the body is .75 m^2, and it is observed that 100 g of maphthalene has sublimated in 45 min. During the experiemnt, both the body and the air were kep at 25oC, at which the vapor pressure and mass diffusivity of naphthalene are 11 Pa and Dab=0.61*10^-5 m^2/s respectively. Determine the heat transfer coefficent under the same flow conditions over the same geometry.

The average heat transfer coefficent for airflow over an odd shaped body is to be determined by mass transfer measurements and using the Chilton-Colburn analogy btwn heat and mass transfer. The experiemnt is conducted by blowing dry air at 1 atm at a free-stream velocity of 2 m/s over a body covered with a layer of naphthalene. The surface area of the body is .75 m^2, and it is observed that 100 g of maphthalene has sublimated in 45 min. During the experiemnt, both the body and the air were kep at 25oC, at which the vapor pressure and mass diffusivity of naphthalene are 11 Pa and Dab=0.61*10^-5 m^2/s respectively. Determine the heat transfer coefficent under the same flow conditions over the same geometry.

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.3P

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