In an air conditioning system, outside air at 34C dry bulb temperature and 65% relative humidity...

 

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In an air conditioning system, outside air at 34C dry bulb temperature and 65% relative humidity is mixed with equal volumes of recirculated air at 20C dry bulb temperature and 14C dew point temperature. After mixing, the mixture is cooled to a dry bulb temperature of 20C. The total system pressure is 90 kPa. Determine: a) Moisture content of air after mixing b) Moisture content of air after cooling c) Enthalpy of air after cooling Question 3 (10 marks) An industrial building at Cooma, New South Wales has a winter sensible heat loss of 59 kW and a negligible latent heat load (latent losses to outside are made-up by latent gains within the space). The space is to be maintained precisely at 24C and 50% RH. Due to the nature of the process, 100 percent outside air is required for ventilation. The outdoor air conditions can be taken as saturated air at 1C. The amount of ventilation air is 3300 L/s and the air is to be preheated, humidified with an adiabatic saturator to the desired humidity, and then reheated. The temperature out of the adiabatic saturator is to be maintained at 15C DB. Determine the following: a) Temperature of the air entering the space to be heated, C b) Heat supplied to preheat coil, kW c) Heat supplied to reheat coil, kW d) Amount of humidification, g/s Draw the cycle on a psychrometric chart. In an air conditioning system, outside air at 34C dry bulb temperature and 65% relative humidity is mixed with equal volumes of recirculated air at 20C dry bulb temperature and 14C dew point temperature. After mixing, the mixture is cooled to a dry bulb temperature of 20C. The total system pressure is 90 kPa. Determine: a) Moisture content of air after mixing b) Moisture content of air after cooling c) Enthalpy of air after cooling Question 3 (10 marks) An industrial building at Cooma, New South Wales has a winter sensible heat loss of 59 kW and a negligible latent heat load (latent losses to outside are made-up by latent gains within the space). The space is to be maintained precisely at 24C and 50% RH. Due to the nature of the process, 100 percent outside air is required for ventilation. The outdoor air conditions can be taken as saturated air at 1C. The amount of ventilation air is 3300 L/s and the air is to be preheated, humidified with an adiabatic saturator to the desired humidity, and then reheated. The temperature out of the adiabatic saturator is to be maintained at 15C DB. Determine the following: a) Temperature of the air entering the space to be heated, C b) Heat supplied to preheat coil, kW c) Heat supplied to reheat coil, kW d) Amount of humidification, g/s Draw the cycle on a psychrometric chart.