(a) Calculate the R-value of a thermal window made of two single panes of glass each 0.125 in. thick and separated by a 0.230-in. air space. (b) By what factor is the transfer of energy by heat through the window reduced by using the thermal window instead of the singlepane window? Include the contributions of inside and outside stagnant air layers.

(a) Calculate the R-value of a thermal window made of two single panes of glass each 0.125 in. thick and separated by a 0.230-in. air space. (b) By what factor is the transfer of energy by heat through the window reduced by using the thermal window instead of the singlepane window? Include the contributions of inside and outside stagnant air layers.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.13P: 1.13 If the outer air temperature in Problem is –2°C, calculate the convection heat transfer...

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