A picture window in a house is 3 feet high by 5 feet long. If the window is 50ºF and the outside air temperature is -10ºF, estimate the heat transfer by natural convection from the window.

What will be an ideal response?


Treating the window as a vertical flat surface, we need to determine the Grshof number and the Grashof/Prandtl product, called the Rayleigh number, Ra. The characteristic length is 3 feet, the temperature difference is 60ºF = 60ºR, and the Prandtl number is about 0.7. For, which we assume is an ideal gas



Physics & Space Science

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What will be an ideal response?

Physics & Space Science