In: Mechanical Engineering
heat transfer
The double-glazed window with a height of 1.2m and a width of 2m
has a gap of stagnant air (k = 0.026W / m ° C) with a width of 12mm
between the glass of 3mm (k = 0.78W / m ° C). On a day when the
outside temperature is kept at 24 ° C, find the continuous heat
transfer rate and inner surface temperature in this glass window.
(Take the heat transfer coefficients h1 = 10W / m² ° C and h2 = 25W
/ m² ° C on the inner and outer surface of the window and neglect
the number of heat transfer coats by radiation)
b) Interpret how the heat transfer would have been if there was a
vacuum between the two glasses (air was completely discharged).