Q1: The following data refer to public hall Winter AC system: 100% Outdoor conditions: P= 101.3 kPa, tab=5°C; Supply conditions: tab = 30°C; = 45% Seating capacity of the hall = z Outdoor air supplied = 0.3 m³/min/person = 3 g/kga If the required comfort condition is achieved by THREE processes: • first preheating, • then adiabatic humidification till = 80%, and finally reheat process to the supply conditions, Draw all processes on the Psychrometric Chart and determine: 1. The air dry-bulb temperature and relative humidity after preheating process 2. The heating capacity of the preheater, in (kW). 3. The heating capacity of the reheater, in (kW). 4. The mass of water required in the humidifier, in (kg/hr). 5. The effectiveness of the humidifier Q2: If the total pressure in Q1 is P= ??, Solve it again using Equations.

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