A stream of warm air with a dry-bulb temperature of 36OC and a wet-bulb temperature of 30OC is mixed adiabatically with a stream of saturated cool air at 12OC. The dry air mass flow rates of the warm and cool airstreams are 8 and 10 kg/s, respectively. Assuming a total pressure of 1 atm, determine  (a) the temperature  (b) the specific humidity   (c) the relative humidity of the mixture

Moist air enters an air conditioning unit at 40°C dry bulb temperature and 45% relative humidity. The air is first passed over cooling coils to remove all of the moisture necessary to achieve the final moisture content and then is passed over heating coils to achieve the final conditions of 20°C dry bulb temperature and 10°C wet bulb temperature. The pressure remains constant at 1 atm throughout the process. (a) Sketch the psychometric diagram for the process. (b) Determine the dew point temperature of the mixture at the inlet of the cooling coils and at the inlet of the heating coils. (c) Calculate the net heat transfer for the entire process, in kJ/kg dry air.

In an air conditioning system, return air at 24°C dry-bulb temperature and 40% relative humidity is mixed with outdoor ambient air at 30°C dry-bulb temperature and 70% relative humidity. The dry air mass flow rate of outdoor air is 20% of the supply air mass flow rate to the space. The pressure is constant at 101.3 kPa.-Calculate the dry-bulb temperature of the supply air in °C.-The humidity ratio of the supply air.-The enthalpy of supply air in kJ/kg.

Saturated air at 13 °C and 1 atm enters the heating section of an air-conditioning system at a rate of 0.5 kg/s and leaves 30 °C. Determine the rate of heat transfer to the air and the exit relative humidity.

A wet cooling tower is to cool 60 kg/s of water from 40 to 33C. Atmospheric Air Enters the tower at 1 atm with a dry bulb and wet bulb temperatures of 22C and 16C  respectively and leaves at 30C with a relative humidity of 95%. Determine (a) volume flow rate of the air into cooling tower (b) the mass flow rate of the require make up water, adn (c) the cooling tower efficiency.

An incoming air flow of 200 m3/h at a temperature of 20°C and a humidity ratio of 0.012 kgv/kga is mixed in a chamber with another incoming air flow of 500 m3/h at a temperature of 15°C and a humidity ratio of 0.008 kgv/kga.   Based on the corresponding mass flow rates (and NOT the original volumetric flow rates) determine: a)      The mass flow rate of the mixed air (i.e., the combination of the two flows) leaving the chamber in kg/s. b)      The temperature of the mixed air leaving the chamber. Please use PyscPro software for solving this question.   Notes: For part (a), you will first need to find the density or specific volume for each state (density = 1/specific volume). The units the 'v' and 'a' are intended as subscripts: ·         kgv = kg_v = kgv = kilogram(s) [vapour] kga = kg_a =kga = kilogram(s) [air]

An air-conditioning system operates at a total pressure of 1 atm and consists of a heating section and anevaporative cooler. Air enters the heating section at 14°C and 60 percent relative humidity at a rate of 30m3/min, and it leaves the evaporative cooler at 25°C and 45 percent relatively humidity. Determine (a) thetemperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in theheating section, and (c) the rate of water added to air in the evaporative cooler.

Air at a dry bulb temperature of 20oC and relative humidity of 80% is to be heated and humidified to 40oC and 40% relative humidity. The following options are available for this objective: (a) by passing air through a heated water-spray air washer; (b) by preheating sensibly, and then passing through a water-spray washer with recirculated water until relative humidity rises to 95% and then again heating sensibly to the final required state. Determine for (a) and (b) the total heating required, the make-up water required in water-spray air washer, and the humidifying efficiency of the recirculated spray water.

Air enters a heating section at 95kPa, 10°C and 30% relative humidity. The air flow rate is 6 m¾/min. The air leaves the heating section at 25°C. Since the psychrometric chart is invalid for problems that are not at atmospheric pressure, perform long-hand calculations and determine the following: (i) the heat addition rate, and (i) the relative humidity of the exiting air.

air flowing at 2 kg / s has a dry bulb temperature of 50 ° C and a wet bulb temperature of 30 ° C, mixed with air flowing at 3kg / s at 25 ° C and a relative humidity of 70%. Using the psycometry chart determine the ratio, enthalpy and temperature of the dry ball