The onset of free convection. Plastic shrink wrap can be used to insulate windows by trapping air between your window and the wrapping. Calculate the critical gap width between the plastic and the window at which free convection will occur on an average winter’s day, when the outside temperature is 41°F and the inside temperature is 68°F. Would you expect there to be more or less heat transfer when the spacing is above this gap? Explain.

The onset of free convection. Plastic shrink wrap can be used to insulate windows by trapping air between your window and the wrapping. Calculate the critical gap width between the plastic and the window at which free convection will occur on an average winter’s day, when the outside temperature is 41°F and the inside temperature is 68°F. Would you expect there to be more or less heat transfer when the spacing is above this gap? Explain.

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 8.37P

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