CENGEL'S 9TH EDITION OF THERMODYNAMICS:
9th Edition
ISBN: 9781260917055
Author: CENGEL
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 14.7, Problem 87P
Humid air is to be conditioned in a constant-pressure process at 1 atm from 39°C dry bulb and 50 percent relative humidity to 17°C dry bulb and 10.8°C wet bulb. 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 state.
- (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) Determine the heat removal by the cooling coils, the heat addition by the heating coils, and the net heat transfer for the entire process, all in kJ/kg dry air.
FIGURE P14–87
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Moist air at 105 kPa, 30° C and 80% relative humidity
flows over a cooling coil in an insulated air-conditioning
duct. Saturated air exists the duct at 100kPa and 15°C.
The saturation pressure of water at 30° C and 15°C are
4.24 kPa and 1.7 kPa, respectively. Molecular weight of
water is 18 g/mol and that of air is 28.94 g/mol. The
mass of water condensing out from the duct is ...
g/kg of dry air (round off to 2 decimal places).
Air at 0° C and 95% relative humidity has to be heated and humidified to 25° C and 40% relative humidity by the following three processes: (a) preheating; (b) adiabatic saturation in a recirculated water air-washer; and (c) reheating to final state. Calculate: 1. The heating required in two heaters; 2. The makeup water required in washer and temperature of washer. Assume effectiveness of washer as 80 per cent
Please assist with this Thermodynamics question. It's urgent.Thanks in advance
Chapter 14 Solutions
CENGEL'S 9TH EDITION OF THERMODYNAMICS:
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...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- 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.arrow_forwardAn air conditioned space is to be supplied with 300 cmm of air at 20°C dry bulb and 40% relative humidity. Unconditioned air from atmosphere at 32°C dry bulb and 28°C dew point is supplied to the dehumidifier coils, from where the same passes on to a heating coil before entering the conditioned space. Determine the cooling required. Solve the problem both from first principles and with Psychrometric chart.arrow_forwardOne m3/s of air at 12°C and 50% RH is heated and humidified using saturated steam at 100 °C to a final state of 38°C and 50% relative humidity. Sketch the process on the psychrometric chart and calculate the following: (a) Mass flow rate (b) Steam flow rate needed (c) Heating coil capacityarrow_forward
- I need the answer as soon as possiblearrow_forwardAn air-conditioning system operates at a total pressure of 1 atm and consists of a heating section and an evaporative cooler. Air enters the heating section at 15OC and 55 percent relative humidity at a rate of 30 m3 /min, and it leaves the evaporative cooler at 25OC and 45 percent relatively humidity. Determine the TOR.arrow_forwardSaturated ambient air with a db-temperature of 5°C and a mass flow rate of 0.9 kg/s is divided into two streams. One stream passes through a heating section and leaves it with a relative humidity of 25%. The conditions of the other stream that bypasses the heater remains unchanged. The two streams are then mixed to produce the supply air stream at 24°C. The pressure is constant at 101.3 kPa. -Determine the partial pressure of water vapor of the heated air in kPa.-The heat input by the heating coil in kW.-The mass flow of air through the bypass section in kg/s.arrow_forward
- 2. An air-conditioning system is to take in outdoor air at 10 C and 30 percent relative humidity at a steady rate of 45 m3/min and to condition it to 25 C and 60 percent relative humidity. The outdoor air is first heated to 22 C in the heating section and then humidified by the injection of hot steam in the humidifying section. Assuming the entire process takes place at a pressure of 100 kPa, determine (a) the rate of heat supply in the heating section and (b) the mass flow rate of the steam required in the humidifying section. 22 C 25 C Heating Hum hiner 7,10°C. 7-25 C = 30%arrow_forward8. Moist air undergoes a heating and humidification process at a pressure of 101.325 kPa from an initial state of 15°C db and 90% relative humidity to a final state at 22°C and 70% relative humidity. If the mass flow rate of the air at the initial state is 24.5 kg da/s, what is the increase in the water content of the air? Express your answer in kg/s. In your written solution, draw the process in the psychrometric chart, show the initial and final state and the values obtained from the chart.arrow_forwardAir 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.arrow_forward
- The air in a room (24.0°C and 30% humidity) with a volume of 96.6 m3 must be replaced every 5 minutes. Outside air at 38.0°C and 70% humidity is chilled to remove some of its water content and then dehumidified to the required temperature. What is the volumetric flow rate (in m3/min) of the humid air entering the chiller?arrow_forwardAir 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.arrow_forwardPlease answer in clear handwritingarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
The Refrigeration Cycle Explained - The Four Major Components; Author: HVAC Know It All;https://www.youtube.com/watch?v=zfciSvOZDUY;License: Standard YouTube License, CC-BY