A vertical, double-pane window(square), which is 1 m on a side and has a 25-mm gap filled withatmospheric air, separates quiescent room air at T; = 20 °C from quiescent ambient air at To = -20 °C. Heatloss through the window is 38 W and the heat transfer coefficient between outer glass surface and theouter air is 3.7 W/m²K. Assume the bulk mean temperature between the room air and inner surface of theglass is 15 °C. Radiation heat transfer as well as thermal resistance associated with conduction along glasspane are neglected.The Nusselt number between the air gap of the two glasses of the window.O a. 4.22O b. 6.21O C. 5.33O d.2.16

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A vertical, double-pane window(square), which is 1 m on a side and has a 25-mm gap filled with atmospheric air, separates quiescent room air at Tj = 20 °C from quiescent ambient air at To = -20 °C. Heat loss through the window is 38 W and the heat transfer coefficient between outer glass surface and the outer air is 3.7 W/m2K. Assume the bulk mean temperature between the room air and inner surface of the glass is 15 °C. Radiation heat transfer as well as thermal resistance associated with conduction along glass pane are neglected. The Nusselt number between the air gap of the two glasses of the window. Оа. 4.22 O b.6.21 O C. 5.33 O d. 2.16

A vertical, double-pane window(square), which is 1 m on a side and has a 25-mm gap filled with atmospheric air, separates quiescent room air at Tj = 20 °C from quiescent ambient air at To = -20 °C. Heat loss through the window is 38 W and the heat transfer coefficient between outer glass surface and the outer air is 3.7 W/m2K. Assume the bulk mean temperature between the room air and inner surface of the glass is 15 °C. Radiation heat transfer as well as thermal resistance associated with conduction along glass pane are neglected. The Nusselt number between the air gap of the two glasses of the window. Оа. 4.22 O b.6.21 O C. 5.33 O d. 2.16

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 8.7P

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