An air-conditioning plant is designed to maintain a room at acondition of 20oC dry bulb and specific humidity 0.0079 when theoutside condition is 30oC dry bulb and 40% percentage saturationand the corresponding heat gains are 18000 W (sensible) and 3600(latent). The supply air contains one-third outside air by mass andthe supply temperature is to be 15oC dry bulb. The plant consistsof a mixing chamber for fresh and recirculated air, an air washerwith chilled spray water with an efficiency of 80%, an after heaterbattery and supply fan. Neglecting temperature changes in fan andducting, calculate:
a. The mass flow rat of supply air necessary;
b. The specific humidity of the supply air;
c. The cooling duty of the washer;
d. The heating duty of the after heater
(use the psychrometric chart assuming the barometric pressure is1.001325 bar)
