Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 14, Problem 14.11P
An open pan of diameter 0.2 m and height 80mm (above water at 27°C) is exposed to ambient air at 27°C and 25% relative humidity. Determine the evaporation rate, assuming that only mass diffusion occurs. Determine the evaporation rate, considering bulk motion.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Problem 1. A sheet of BCC iron 1 mm thick was exposed to a carburizing gas atmosphere on
one side and a decarburizing atmosphere on the other side at 725°C. After having reached steady
state, the iron was quickly cooled to room temperature. The carbon concentrations at the two
surfaces of the sheet were determined to be 0.012 and 0.0075 wt%, respectively. Compute the
diffusion coefficient if the diffusion flux is 1.4 × 10 -³ kg/m²-s.
(a) Derive an expression for the saturation vapour pressure of water in equilibrium with its vapour
under the assumptions that the latent heat of vaporisation is temperature independent, that the vapour
can be treated as an ideal gas and that the volume occupied by the vapour is much_greater than the.
volume occupied by the liquid.
(b) Calculate the relative humidity (in %) for an air temperature of 24 °C and dew point temperature
of 20 °C. (The saturation vapour pressure at 0 °C is 611 Pa, the specific gas constant for water vapour
is 461.5 J kg' K and latent heat of vaporisation of water is 2.5 x 10° J kg).
consider a room filled with air at 15 degrees centigrade and relative humidity 75 percent,calculate the temperature of the windows of the room at which air starts condensing at inner surface?
Chapter 14 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 14 - Assuming air to be composed exclusively O2 and N2...Ch. 14 - Consider an ideal gas mixture of n species. (a)...Ch. 14 - A mixture of CO2 and N2 is in a container at 25C ,...Ch. 14 - A He-Xe mixture containing 0.75 mole fraction of...Ch. 14 - Estimate values of the mass diffusivity for binary...Ch. 14 - Consider air in a closed, cylindrical container...Ch. 14 - An old-fashioned glass apothecary jar contains a...Ch. 14 - Consider the evaporation of liquid A into a column...Ch. 14 - An open pan of diameter 0.2 m and height 80mm...Ch. 14 - A spherical droplet of liquid A and radius...
Ch. 14 - The presence of a small amount of air may cause a...Ch. 14 - A laboratory apparatus to measure the diffusion...Ch. 14 - A thin plastic membrane is used to separate helium...Ch. 14 - Prob. 14.16PCh. 14 - Consider the radial diffusion of a gaseous species...Ch. 14 - Prob. 14.18PCh. 14 - Prob. 14.19PCh. 14 - Prob. 14.20PCh. 14 - Hydrogen at a pressure of 2 atm flows within a...Ch. 14 - Prob. 14.22PCh. 14 - Insulation degrades (experiences an increase in...Ch. 14 - Prob. 14.24PCh. 14 - Helium gas at 25°C and 4 bars is stored in a...Ch. 14 - Prob. 14.26PCh. 14 - An experiment is designed to measure the partition...Ch. 14 - Ultra-pure hydrogen is required in applications...Ch. 14 - Nitric oxide (NO) emissions from automobile...Ch. 14 - Pulverized coal pellets, which may be approximated...Ch. 14 - To enhance the effective surface, and hence the...Ch. 14 - A platinum catalytic reactor in an automobile is...Ch. 14 - A novel process has been proposed to create a...Ch. 14 - Consider a spherical organism of radius r0 within...Ch. 14 - Prob. 14.35PCh. 14 - Consider combustion of hydrogen gas in a mixture...Ch. 14 - Prob. 14.37PCh. 14 - As an employee of the Los Angeles Air Quality...Ch. 14 - Prob. 14.39PCh. 14 - A large sheet of material 4() mm thick contains...Ch. 14 - Prob. 14.41PCh. 14 - Prob. 14.43PCh. 14 - Prob. 14.44PCh. 14 - Prob. 14.46PCh. 14 - If an amount of energy Q0(J/m2) is released...Ch. 14 - The presence of CO2 in solution is essential to...Ch. 14 - Consider a DVD similar to that of Problem 5.99. To...Ch. 14 - Prob. 14.50PCh. 14 - Prob. 14.51PCh. 14 - Prob. 14.52PCh. 14 - Prob. 14.55PCh. 14 - A person applies an insect repellent onto an...
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
- Explain the cooling effect of evaporation in terms of latent heat of evaporation.arrow_forwarddont type solution stepsarrow_forwardIs latent heat load of infiltration necessarily zero when the humidity ratio (absolute humidity) of the hot outside air in summer is the same as that of inside air? Explain.arrow_forward
- Moist air contains 0.025 kg water vapour per cubic metre of themixture at 313 K and 101.3 kPa. Calculate the following: The absolute humidity of the airarrow_forwardI need it fast handwritten onlyarrow_forwardNow consider an air sample with a temperature of 34°C and a relative humidity of 62%, what is its mixing ratioarrow_forward
- large dry air is flowing over a surface from which benzene is evaporating with 1 atm absolute pressure as total pressure. The partial pressure of benzene at the surface is the vapor pressure at 298 K which is (0.42 atm). The Ke has been estimated to be (6.5*10s kmol / s.m'. mol vol.). Calculate the vaporizing rate benzene, and the individual mass transfer coefficient Ky? (R=0.000082)arrow_forwardGaseous hydrogen at a constant pressure is to flow within the inside of a thin-walled cylindrical tube of nickel. Consider the steady-state diffusion of hydrogen through the walls of this cylindrical nickel tube. One design calls for a diffusion flux of 5 x 10-8 mol/m2.s, a tube radius of 0.125 m, and inside and outside pressures of 0.5065 MPa (5 atm) and 0.0203 MPa (0.2 atm), respectively; the maximum allowable temperature is 450°C. In case the wall thickness is 2 mm and the yield strength is greater than twice the circumferential stress, what would be the temperature to give this diffusion flux and yet ensure that the tube walls will not experience any permanent deformation? i °Carrow_forwardA polyethylene (PE) membrane is being used as an oxygen barrier. Oxygen is being supplied on the high pressure side at 0.25 kg/m3, and on the other side is a vacuum (concentration of oxygen is 0 kg/m3). If the desired flux is 4E-8 kg/m2s, what should the thickness of the PE membrane be? Answer in mm. The diffusion coefficient of oxygen in PE at the operating temperature is 4.5E-11 m2/s. Equation is J= -D(C1-C2/X1-X2)arrow_forward
- 9. What is diffusion and convection? Provide an example for each!arrow_forwardthe sample for 10 hours at 930°C to achieve 0.4% carbon, 1cm from the surface. To Consider the carbonization of steel that has a background of 0.1% carbon. The plan is to heat accomplish this, what concentration of carbon must be maintained at the surface? The diffusion coefficient is D = 2.3 x 105 m²/s.arrow_forwardThe wear resistance of a steel shaft is to be improved by hardening its surface by increasing the nitrogen content within an outer surface layer as a result of nitrogen diffusion into the steel; the nitrogen is to be supplied from an external nitrogen-rich gas at an elevated and constant temperature. The initial nitrogen content of the steel is 0.0020wt%, whereas the surface concentration is to be maintained at 0.50wt%. For this application, a nitrogen content of 0.10wt% at a position 0.40 mm below the surface is desired. I. Will this process be a steady state or non-steady state process? Why? II. Would you expect nitrogen to diffuse by a vacancy mechanism or an interstitial mechanism? Why?arrow_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
Ficks First and Second Law for diffusion (mass transport); Author: Taylor Sparks;https://www.youtube.com/watch?v=c3KMpkmZWyo;License: Standard Youtube License