Thermodynamics: An Engineering Approach
9th Edition
ISBN: 9781259822674
Author: Yunus A. Cengel Dr., Michael A. Boles
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Question
Chapter 14.7, Problem 21P
To determine
What is dew point temperature.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
14.10. A liquor containing 15 per cent
solids is concentrated to 55 per cent
solids in a double-effect evaporator.
operating at a pressure in the second
effect of 18 kN/m². No crystals are
formed. The flowrate of feed is 2.5 kg/
s at 375 K with a specific heat capacity
of 3.75 kJ/kg K. The boiling-point rise of
the concentrated liquor is 6 deg K and the
steam fed to the first effect is at 240 kN/
m². The overall heat transfer coefficients
in the first and second effects are 1.8 and
0.63 kW/m²K. respectively. If the heat
transfer area is to be the same in each
effect, what areas should be specified?
14.25.2.5 kg/s of a solution at 288 K
containing 10 per cent of dissolved solids
is fed to a forward-feed double-effect
evaporator, operating at 14 kN/m² in the
last effect. If the product is to consist of
a liquid containing 50 per cent by mass of
dissolved solids and dry saturated steam
is fed to the steam coils, what
PROBLEMS
1179
should be the pressure of the steam? The
surface in each effect is 50 m² and the
coefficients for heat transfer in the first
and second effects are 2.8 and 1.7 kW/
m² K, respectively. It may be assumed
that the concentrated solution exhibits a
boiling-point rise of 5 deg K, that the latent
heat has a constant value of 2260 kJ/kg
and that the specific heat capacity of the
liquid stream is constant at 3.75 kJ/kg K
O
: +0
العنوان
use only
5) A 100 kg batch of granular solids
containing 30% moisture is to be dried in
a tray drier to
15.5% by passing a current of air at 350
K tangentially across its surface at a
velocity of 1.8
m/s. If the constant rate of drying under
these conditions is 0.7 g/s m2
and the critical moisture
content is 15%, calculate the
approximate drying time. Assume the
drying surface to be 0.03
m2
/kg dry mass.
мони
Chapter 14 Solutions
Thermodynamics: An Engineering Approach
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
- give me solution math not explinarrow_forward۲/۱ : +0 العنوان seoni 4) 1 Mg (dry weight) of a non-porous solid is dried under constant drying conditions with an air velocity of 0.75 m/s parallel to the drying surface. The area of drying surface is 55 m2 If initial rate of drying is 0.3 g/m2 s, how long it will take to dry a material from 0.15 to 0.025 kg water/kg dry solid? The critical moisture content is 0.125 and the equilibrium moisture is negligible. The falling rate of drying is linear in moisture content. If air velocity increases to 4 m/s, what will be the anticipated saving in drying time? 0 ostherarrow_forward14.23. A double-effect forward-feed evaporator is required to give a product consisting of 30 per cent crystals and a mother liquor containing 40 per cent by mass of dissolved solids. Heat transfer coefficients are 2.8 and 1.7 kW/m² K in the first and second effects respectively. Dry saturated steam is supplied at 375 kN/m² and the condenser operates at 13.5 kN/ m². (a) What area of heating surface is required in each effect assuming the effects are identical, if the feed rate is 0.6 kg/s of liquor, containing 20 per cent by mass of dissolved solids, and the feed temperature is 313 K? (b) What is the pressure above the boiling liquid in the first effect? The specific heat capacity may be taken as constant at 4.18 kJ/kg K. and the effects of boiling-point rise and of hydrostatic head may be neglected. O Oarrow_forward
- 5) A 100 kg batch of granular solids containing 30% moisture is to be dried in a tray drier to 15.5% by passing a current of air at 350 K tangentially across its surface at a velocity of 1.8 m/s. If the constant rate of drying under these conditions is 0.7 g/s m2 and the critical moisture content is 15%, calculate the approximate drying time. Assume the drying surface to be 0.03 m2 /kg dry mass. Oarrow_forwardSolve for v and Iarrow_forwardG = 0.350MPa, P = 900N, a=20mm, b=50mm, c=80mmarrow_forward
- [20 Points] Use Method of Sections to draw the shear-force and bending-moment diagrams for the simply supported beam shown. Determine the maximum bending moment that occurs in the span. 1.5 kN/m 4 m 2 m Carrow_forward14.10. A liquor containing 15 per cent solids is concentrated to 55 per cent solids in a double-effect evaporator. operating at a pressure in the second effect of 18 kN/m². No crystals are formed. The flowrate of feed is 2.5 kg/ s at 375 K with a specific heat capacity of 3.75 kJ/kg K. The boiling-point rise of the concentrated liquor is 6 deg K and the steam fed to the first effect is at 240 kN/ m². The overall heat transfer coefficients in the first and second effects are 1.8 and 0.63 kW/m²K. respectively. If the heat transfer area is to be the same in each effect, what areas should be specified? D Aarrow_forward14.9. A forward feed double-effect vertical evaporator, with equal heating areas in each effect, is fed with 5 kg/s of a liquor of specific heat capacity of 4.18 kJ/kg K. and with no boiling point rise, so that 50 per cent of the feed liquor is evaporated. The overall heat transfer coefficient in the second effect is 75 per cent of that in the first effect. Steam is fed at 395 K and the boiling point in the second effect is 373 K. The feed is heated by an external heater to the boiling point in the first effect. It is decided to bleed off 0.25 kg/s of vapour from the vapour line to the second effect for use in another process. If the feed is still heated to the boiling point of the first effect by external means, what will be the change in steam consumption of the evaporator unit? For the purpose of calculation, the latent heat of the vapours and of the steam may both be taken as 2230 kJ/kg Ад Oarrow_forward
- correct the shaft misalignment in a cars transmission system, determine the offset distance required to correct the shaft misalignment of 4 degrees in a rotating system. shaft diameter is 4cm.arrow_forward14.14. A three-stage evaporator is fed with 1.25 kg/s of a liquor which is concentrated from 10 to 40 per cent solids by mass. The heat transfer coefficients may be taken as 3.1, 2.5 and 1.7 kW/m² K, respectively, in each effect. Calculate the steam flow at 170 kN/m² and the temperature distribution in the three effects, if: (a) the feed is at 294 K, and (b) the feed is at 355 K. Forward feed is used in each case and the values of U are the same for the two systems. The boiling point in the third effect is 325 K and the liquor has no boiling point rise. Oarrow_forwardForm of the second question 3 Question 2: 500 In the figure shown, gear 2 rotates at 1000rpm. It transmits a power of 5kw to gear 4 via gear Loose 3 idler all gears spur, angle Gear pressure =200, and inclusion = 5m. Draw Analyze the forces on gear 3 and then find the reactions on Column 6, knowing the number of teeth N₂ = 12, N3 = 60, N₁ = 40arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Refrigeration and Air Conditioning Technology (Mi...Mechanical EngineeringISBN:9781305578296Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill JohnsonPublisher:Cengage Learning
Refrigeration and Air Conditioning Technology (Mi...
Mechanical Engineering
ISBN:9781305578296
Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher:Cengage Learning
Thermodynamics: Maxwell relations proofs 1 (from ; Author: lseinjr1;https://www.youtube.com/watch?v=MNusZ2C3VFw;License: Standard Youtube License