[20 Marks] Problem #3 Moist air at 40C and 50% relative humidity enters a dehumidifier (state...

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[20 Marks] Problem #3 Moist air at 40C and 50% relative humidity enters a dehumidifier (state 1), operating at steady state with a volumetric flow rate of 350 m/min. The moist air passes over a cooling coil and water vapor condenses. Condensate exits the dehumidifier saturated at 10 C. Saturated moist air exits the cooling coil at the same temperature (state 2). There is no significant loss of energy by heat transfer to the surroundings and the total pressure remains constant at 1 atm. Use the Psychrometric chart and determine the following: (a) The mass flow rate of the dry air, in kg/min, (b) The rate at which water is condensed, in kg per kg of dry air (c) The required refrigerating capacity, in kJ/min. The saturated moist air at state 2 passes over a heating coil and come out at 20 C (state 3). Determine: (d) The relative humidity of the exit air stream at state 3 (e) The amount of heat supplied to the heating coil, in kJ/min (f) Draw all the processes on the Psychrometric chart State Humidity ratio (0) Mixture enthalpy (kJ/kgar) 2 3 Cooling coil Condensate, saturated at T = 10C Heating coil Saturated mixture 10C [20 Marks] Problem #3 Moist air at 40C and 50% relative humidity enters a dehumidifier (state 1), operating at steady state with a volumetric flow rate of 350 m/min. The moist air passes over a cooling coil and water vapor condenses. Condensate exits the dehumidifier saturated at 10 C. Saturated moist air exits the cooling coil at the same temperature (state 2). There is no significant loss of energy by heat transfer to the surroundings and the total pressure remains constant at 1 atm. Use the Psychrometric chart and determine the following: (a) The mass flow rate of the dry air, in kg/min, (b) The rate at which water is condensed, in kg per kg of dry air (c) The required refrigerating capacity, in kJ/min. The saturated moist air at state 2 passes over a heating coil and come out at 20 C (state 3). Determine: (d) The relative humidity of the exit air stream at state 3 (e) The amount of heat supplied to the heating coil, in kJ/min (f) Draw all the processes on the Psychrometric chart State Humidity ratio (0) Mixture enthalpy (kJ/kgar) 2 3 Cooling coil Condensate, saturated at T = 10C Heating coil Saturated mixture 10C