PROBLEM 6.11 A humidity box for laboratory use is constructed from panes of window glass of thickness 4 mm. The temperature inside the box is maintained at 90°C and the ambient room temperature is 25℃·The heat transfer coefficients at the inner and outer surfaces of the box are, respectively, 20 and 60 W.m-2.K
(a) Calculate the maximum relative humidity that can be used in the box without condensation occurring on the inner surfaces.
I know the relative humidity is the amount of water vapour pressure in air as % needed for saturation at the same temp.
What needs to be true for condensation to not occur on the inner surfaces? Would condensation not occur given any difference of temperature?