THERMODYNAMICS (LL)-W/ACCESS >IP<
9th Edition
ISBN: 9781260666557
Author: CENGEL
Publisher: MCG CUSTOM
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Chapter 14.7, Problem 18P
A room contains air at 85°F and 13.5 psia at a relative humidity of 60 percent. Determine (a) the partial pressure of dry air, (b) the specific humidity, and (c) the enthalpy per unit mass of dry air.
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A sample of outdoor air (Point 1) has a dry-
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Chapter 14 Solutions
THERMODYNAMICS (LL)-W/ACCESS >IP<
Ch. 14.7 - What is the difference between dry air and...Ch. 14.7 - What is vapor pressure?Ch. 14.7 - What is the difference between the specific...Ch. 14.7 - Can the water vapor in air be treated as an ideal...Ch. 14.7 - Explain how vapor pressure of the ambient air is...Ch. 14.7 - Is the relative humidity of saturated air...Ch. 14.7 - Moist air is passed through a cooling section...Ch. 14.7 - How will (a) the specific humidity and (b) the...Ch. 14.7 - Prob. 9PCh. 14.7 - Consider a tank that contains moist air at 3 atm...
Ch. 14.7 - Is it possible to obtain saturated air from...Ch. 14.7 - Why are the chilled water lines always wrapped...Ch. 14.7 - How would you compare the enthalpy of water vapor...Ch. 14.7 - A tank contains 15 kg of dry air and 0.17 kg of...Ch. 14.7 - Prob. 15PCh. 14.7 - An 8-m3 tank contains saturated air at 30C, 105...Ch. 14.7 - Determine the masses of dry air and the water...Ch. 14.7 - A room contains air at 85F and 13.5 psia at a...Ch. 14.7 - Prob. 19PCh. 14.7 - Prob. 20PCh. 14.7 - Prob. 21PCh. 14.7 - In summer, the outer surface of a glass filled...Ch. 14.7 - In some climates, cleaning the ice off the...Ch. 14.7 - Andy and Wendy both wear glasses. On a cold winter...Ch. 14.7 - Prob. 25PCh. 14.7 - Prob. 26PCh. 14.7 - Prob. 27PCh. 14.7 - A thirsty woman opens the refrigerator and picks...Ch. 14.7 - The air in a room has a dry-bulb temperature of...Ch. 14.7 - Prob. 31PCh. 14.7 - Prob. 32PCh. 14.7 - Prob. 33PCh. 14.7 - How do constant-enthalpy and...Ch. 14.7 - At what states on the psychrometric chart are the...Ch. 14.7 - How is the dew-point temperature at a specified...Ch. 14.7 - Can the enthalpy values determined from a...Ch. 14.7 - Atmospheric air at a pressure of 1 atm and...Ch. 14.7 - Prob. 39PCh. 14.7 - Prob. 40PCh. 14.7 - Prob. 41PCh. 14.7 - Atmospheric air at a pressure of 1 atm and...Ch. 14.7 - Reconsider Prob. 1443. Determine the adiabatic...Ch. 14.7 - What does a modern air-conditioning system do...Ch. 14.7 - How does the human body respond to (a) hot...Ch. 14.7 - How does the air motion in the vicinity of the...Ch. 14.7 - Consider a tennis match in cold weather where both...Ch. 14.7 - Prob. 49PCh. 14.7 - Prob. 50PCh. 14.7 - Prob. 51PCh. 14.7 - Prob. 52PCh. 14.7 - What is metabolism? What is the range of metabolic...Ch. 14.7 - Why is the metabolic rate of women, in general,...Ch. 14.7 - What is sensible heat? How is the sensible heat...Ch. 14.7 - Prob. 56PCh. 14.7 - Prob. 57PCh. 14.7 - Prob. 58PCh. 14.7 - Prob. 59PCh. 14.7 - Repeat Prob. 1459 for an infiltration rate of 1.8...Ch. 14.7 - An average (1.82 kg or 4.0 lbm) chicken has a...Ch. 14.7 - An average person produces 0.25 kg of moisture...Ch. 14.7 - How do relative and specific humidities change...Ch. 14.7 - Prob. 64PCh. 14.7 - Humid air at 150 kPa, 40C, and 70 percent relative...Ch. 14.7 - Humid air at 40 psia, 50F, and 90 percent relative...Ch. 14.7 - Prob. 67PCh. 14.7 - Air enters a 30-cm-diameter cooling section at 1...Ch. 14.7 - Prob. 69PCh. 14.7 - Prob. 70PCh. 14.7 - Why is heated air sometimes humidified?Ch. 14.7 - Air at 1 atm, 15C, and 60 percent relative...Ch. 14.7 - Air at 14.7 psia, 35F, and 50 percent relative...Ch. 14.7 - An air-conditioning system operates at a total...Ch. 14.7 - Prob. 75PCh. 14.7 - Why is cooled air sometimes reheated in summer...Ch. 14.7 - Atmospheric air at 1 atm, 30C, and 80 percent...Ch. 14.7 - Ten thousand cubic feet per hour of atmospheric...Ch. 14.7 - Air enters a 40-cm-diameter cooling section at 1...Ch. 14.7 - Repeat Prob. 1479 for a total pressure of 88 kPa...Ch. 14.7 - On a summer day in New Orleans, Louisiana, the...Ch. 14.7 - Prob. 83PCh. 14.7 - Prob. 84PCh. 14.7 - Prob. 85PCh. 14.7 - Saturated humid air at 70 psia and 200F is cooled...Ch. 14.7 - Humid air is to be conditioned in a...Ch. 14.7 - Atmospheric air at 1 atm, 32C, and 95 percent...Ch. 14.7 - Prob. 89PCh. 14.7 - Prob. 90PCh. 14.7 - Does an evaporation process have to involve heat...Ch. 14.7 - Prob. 92PCh. 14.7 - Prob. 93PCh. 14.7 - Air enters an evaporative (or swamp) cooler at...Ch. 14.7 - Prob. 95PCh. 14.7 - Air at 1 atm, 20C, and 70 percent relative...Ch. 14.7 - Two unsaturated airstreams are mixed...Ch. 14.7 - Consider the adiabatic mixing of two airstreams....Ch. 14.7 - Two airstreams are mixed steadily and...Ch. 14.7 - A stream of warm air with a dry-bulb temperature...Ch. 14.7 - Prob. 104PCh. 14.7 - Prob. 105PCh. 14.7 - How does a natural-draft wet cooling tower work?Ch. 14.7 - What is a spray pond? How does its performance...Ch. 14.7 - The cooling water from the condenser of a power...Ch. 14.7 - A wet cooling tower is to cool 60 kg/s of water...Ch. 14.7 - Prob. 110PCh. 14.7 - Prob. 111PCh. 14.7 - Water at 30C is to be cooled to 22C in a cooling...Ch. 14.7 - Prob. 113PCh. 14.7 - Prob. 114RPCh. 14.7 - Determine the mole fraction of dry air at the...Ch. 14.7 - Prob. 116RPCh. 14.7 - Prob. 117RPCh. 14.7 - Prob. 118RPCh. 14.7 - Prob. 119RPCh. 14.7 - Prob. 120RPCh. 14.7 - Prob. 121RPCh. 14.7 - Prob. 122RPCh. 14.7 - Prob. 124RPCh. 14.7 - Prob. 125RPCh. 14.7 - Prob. 126RPCh. 14.7 - Prob. 128RPCh. 14.7 - Prob. 129RPCh. 14.7 - Air enters a cooling section at 97 kPa, 35C, and...Ch. 14.7 - Prob. 131RPCh. 14.7 - Atmospheric air enters an air-conditioning system...Ch. 14.7 - Humid air at 101.3 kPa, 36C dry bulb and 65...Ch. 14.7 - An automobile air conditioner uses...Ch. 14.7 - Prob. 135RPCh. 14.7 - Prob. 137RPCh. 14.7 - Conditioned air at 13C and 90 percent relative...Ch. 14.7 - Prob. 141FEPCh. 14.7 - A 40-m3 room contains air at 30C and a total...Ch. 14.7 - A room is filled with saturated moist air at 25C...Ch. 14.7 - Prob. 144FEPCh. 14.7 - The air in a house is at 25C and 65 percent...Ch. 14.7 - Prob. 146FEPCh. 14.7 - Air at a total pressure of 90 kPa, 15C, and 75...Ch. 14.7 - On the psychrometric chart, a cooling and...Ch. 14.7 - On the psychrometric chart, a heating and...Ch. 14.7 - An airstream at a specified temperature and...
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- Air enters a cooling tower at a rate of 1100 cubic meters per minute, at 15°C and 65% relative humidity. Atmospheric pressure is 100 kPa. Water enters the tower at 38°C and leaves at 17°C. Air leaves the tower at 31°C and saturated. Using a psychrometric chart calculate the absolute humidity of the air leaving the cooling tower. 0.029 kg water vapour/kg air 0.069 kg water vapour/kg air O 0.0101 kg water vapour/kg air 0.364 kg water vapour/kg airarrow_forwardAir at a temperature of 26.7C and a total pressure of 200 kPa contains water vapor with a partial pressure of 2.8 kPa. Determine: (a) the percentage humidity, (b) relative humidity, (c) absolute humidity (d) humid heat in kJ/kg-K (e) wet bulb temperature, and (f) humid volume. Ans: (a) 79.7% (b) 80% (c) 0.00881 (d) 1.0215 (e) 21.2C (f) 0.4435 m3/kg d.a.arrow_forwardroom contains air at 30 degrees * C and a total pressure of 96.0 kPa with a relative humidity of 75 percen ermine (a) the partial pressure of dry air and (b) the specific humidity.arrow_forward
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