Reference no: EM132584664
ME321 Refrigeration and Air Conditioning Assignment -
Q1. For 1 atm atmospheric pressure, dry bulb temperature is 30oC and relative humidity is 60%. Using steam table, find partial pressures of vapour and dry air, degree of saturation and dew point temperature. Calculate the amount of water vapour condensed if the air is cooled at constant pressure to 5oC. Show the process on the psychrometric chart and verify all these values.
Q2. A piston cylinder has 100 Kg of saturated moist air at 1 bar and 5oC. Find the heat transfer and the final relative humidity if it is heated to 45oC in an isobaric process. Now the air is compressed isothermally to 2 bar, what is the final state?
Q3. The room has to be maintained at a temperature of 22oC and 50% relative humidity. The supply air temperature is 14?C with outside conditions as 32oC DBT and 24oC WBT. The sensible and latent heat gain are given as 6 kW and 1.2 kW, respectively. The recirulated to fresh air ratio is 3:1. Calculate the total load on the plant, supply air conditions and by pass factor of the cooling and dehumidifying coil.
Q4. A winter air conditioning system maintains the building at 24oC DBT and 50% RH. The room load is given as: Sensible heat loss = 42 kW; Latent heat gain = 18 kW. The system comprises of a cooling and dehumidifying coil and a re-heater. Outside air is at 2oC DBT and 40% RH and is mixed with the room air in the ratio 1:5. After cooling and dehumidification, the state of air mixture is 9oC DBT and 90% RH. Determine the supply condition and total load on the plant.
Q5. In the duct layout shown below, determine the duct sizes of all sections and fan total pressure using Equal friction method. Select a velocity of 8 m/s in section A. Also assume dynamic loss coefficient in elbow K = 0.22, and static regain factor in fitting or branching R = 0.75. Static pressure at each outlet is 3 mm of water. Find the diameter of section F if no dampering is required in the section.
