At steady state, moist air is to be supplied to a

Chapter 12, Problem 12.90

(choose chapter or problem)

At steady state, moist air is to be supplied to a classroom at a specified volumetric flow rate and temperature T. Air is removed from the classroom in a separate stream at a temperature of \(27^{\circ} \mathrm{C}\) and 50% relative humidity. Moisture is added to the air in the room from the occupants at a rate of 4.5 kg/h. The moisture can be regarded as saturated vapor at \(33^{\circ} \mathrm{C}\). Heat transfer into the occupied space from all sources is estimated to occur at a rate of 34,000 kJ/h. The pressure remains uniform at 1 atm.

(a) For a supply air volumetric flow rate of \(40 \mathrm{m}^{3} / \mathrm{min}\), determine the supply air temperature T, in \({ }^{\circ} \mathrm{C}\), and the relative humidity.

(b) Plot the supply air temperature, in \({ }^{\circ} \mathrm{C}\), and relative humidity, each versus the supply air volumetric flow rate ranging from 35 to \(90 \mathrm{m}^{3} / \mathrm{min}\).