1. A 1 meter by 1 meter window is constructed of two panes of glass, each 3 mm thick and 3 mm apart, with Nitrogen sealed between them (no convection or radiation in Nitrogen - treat as a solid). On a sunny winter day when the outside surroundings are -20°C and the air temperature is - 20°C, what is the loss of heat through the window if the inside room temperature is 20°C? What is the temperature on both sides of each pane of glass? Given: hr = 5.9 W/m²k, h=2 w/m²k (for both inside and outside), Kglass = 1.4 W/m k, KNitrogen = 0.0259 W/m k (State all assumptions and Show All Work)

1. A 1 meter by 1 meter window is constructed of two panes of glass, each 3 mm thick and 3 mm apart, with Nitrogen sealed between them (no convection or radiation in Nitrogen - treat as a solid). On a sunny winter day when the outside surroundings are -20°C and the air temperature is - 20°C, what is the loss of heat through the window if the inside room temperature is 20°C? What is the temperature on both sides of each pane of glass? Given: hr = 5.9 W/m²k, h=2 w/m²k (for both inside and outside), Kglass = 1.4 W/m k, KNitrogen = 0.0259 W/m k (State all assumptions and Show All Work)

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 8.26P

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