re: winter humidification wastes energy
29 oct 2004
>...how can one easily determine the tr when standing in the middle of
>a room where three walls are conventional, interior walls near ta, but
>one is a large amount of double-pane glass to a 20f exterior night??
the inside surface of an r2 window with an r0.66 inside airfilm might
be 20+2(70-20)/2.66 = 57.5 on a 20 f night. you can calculate tr using
solid angles. if the room is square and 3 walls are 70 f and one is 57.5,
tr = (270x70+90x57.5)/360 = 66.9, for an observer in the middle of the
room, ignoring the floor and ceiling.
the sbse tool kit contains a grey golf ball for slipping over a probe
to measure the mean radiant temperature.