A 0.5 m x 2.5 m double-pane window consists of two 4.5-mm-thick layers of glass (k = 0.75 W/m·K) that are separated by a 2.5 mm air gap (kair = 0.025 W/m·K). The heat flow through the air gap is assumed to be by conduction. The inside and outside air temperatures are 20°C and - 1°C, respectively, and the inside and outside heat transfer coefficients are 32 and 12W/m2 ·K. 3.1) Draw a representation of the setup with the thermal resistance network 3.2) Determine the daily rate of heat loss through the window in steady operation. 3.3) Calculate the temperature difference across the largest thermal resistance.

A 0.5 m x 2.5 m double-pane window consists of two 4.5-mm-thick layers of glass (k = 0.75 W/m·K) that are separated by a 2.5 mm air gap (kair = 0.025 W/m·K). The heat flow through the air gap is assumed to be by conduction. The inside and outside air temperatures are 20°C and - 1°C, respectively, and the inside and outside heat transfer coefficients are 32 and 12W/m2 ·K. 3.1) Draw a representation of the setup with the thermal resistance network 3.2) Determine the daily rate of heat loss through the window in steady operation. 3.3) Calculate the temperature difference across the largest thermal resistance.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.1DP

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