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
Videos
Textbook Question
Chapter 11, Problem 11.67P
Exhaust gas from a furnace is used to preheat the combustion air supplied to the furnace burners. The gas,which has a flow rate of 15 kg/s and an inlet temperatureof 1100 K, passes through a bundle of tubes, while theair, which has a how rate of 10 kg/s and an inlet temperature of 300 K, is in cross flow over the tubes. Thetubes are unfinned, and the overall heat transfer coefficient is
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
a one shell and two tube pass heat exchanger, coolant enters the tube at 4.81 kg/s (spread over 72 tubes with each tube being 0.01 m in diameter and 1.95 m length) at an initial temperature of 25 C. Water enters the shell at 2.5 kg/s at an initial temperature of 5 C. The average convection coefficient of the water is known to be 1e4 W/m2.K. What is the overall heat transfer coefficient, assuming no fouling, negligible tube thermal resistance and near-identical inner and outer tube surfaces? What is the actual heat transfer rate? What is the coolant outlet temperature?
The coolant properties are Cp = 1040 J/kg.K, μ = 7.65e-4 kg/s.m, k = 0.058 W/m.K and Pr = 14. Assume the water Cp = 4200 J/kg.K.
Consider the flow of motor oil (cp=2048 J/kg K) through a copper tube ofthin wall at a rate of 0.3 kg/s. The oil enters the copper tubes at atemperature of 80°C that is cooled by means of water that enters at 20°C. Temperatureoutlet of the oil cannot be higher than 40°C. The convective coefficient ofheat transfer from the oil side is 750W/m2 K and from the water side 350W/m2 K. IfThe outlet temperature of the water is measured at 32°C and a heat exchanger is considered.double tube in parallel.
Determine:
a) Mass flow rate of the water.
b) The difference of log mean temperatures.
c) the area of the heat exchanger.
A cylindrical heat exchanger is used to warm up a stream of 0.15 Kg s-l cold air from a temperature
of 200 K to 300 K, after which it is released into the atmosphere. The air enters and leaves the
heat exchanger through a pipe with a diameter of 5 cm. The heat exchanger is of a "Shell and tube
design" as shown below and the air flows through the inside of the tubes. The internal diameter of
the shell is 30 cm. There are 40 tubes each with a diameter of 1 cm in the heat exchange.
It can be assumed that there is no friction in the system. The only change in the gas density occur
inside the tubes, elsewhere, the gas can be considered incompressible. The density of the air at 300
K is 1.23 Kg m-3. The viscosity of air at 200 K is 1.1 x 10-5 kg m-l s-l; at 300 K it is 1.8 x10-5 kg
m-! s-l. Water of enters the heat exchanger at 350 K and leaves at 320 K.
a) Suggest suitable material for the tubes and shell for water to be sea water or feed water.
b) Comment of the effect of fouling on the…
Chapter 11 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 11 - In a fire-tube boiler, hot products of combustion...Ch. 11 - A shell-and-tube heat exchanger is to heat an...Ch. 11 - A steel tube (k=50W/mK) of inner and outer...Ch. 11 - A heat recovery device involves transferring...Ch. 11 - A novel design for a condenser consists of a tube...Ch. 11 - The condenser of a steam power plant...Ch. 11 - Thin-walled aluminum tubes of diameter D = 10mmare...Ch. 11 - A tinned-tube, cross-how heat exchanger is to use...Ch. 11 - Water at a rate of 45,500kg/h is heated from 80...Ch. 11 - A novel heat exchanger concept consists of a...
Ch. 11 - Prob. 11.12PCh. 11 - A process fluid having a specific heat of...Ch. 11 - A shell-and-tube exchanger (two shells, four tube...Ch. 11 - Consider the heat exchanger of Problem 11.14....Ch. 11 - The hot and cold inlet temperatures to a...Ch. 11 - A concentric tube heat exchanger of length L = 2 m...Ch. 11 - A counterflow, concentric tube heat exchanger is...Ch. 11 - Consider a concentric tube heat exchanger with an...Ch. 11 - A shell-and-tube heat exchanger must be designed...Ch. 11 - A concentric tube heat exchanger for cooling...Ch. 11 - A counterflow, concentric tube heat exchanger used...Ch. 11 - An automobile radiator may be viewed as a...Ch. 11 - Hot air for a large-scale drying operation is to...Ch. 11 - In a dairy operation, milk at a flow rate of 250...Ch. 11 - The compartment heater of an automobile...Ch. 11 - A counterflow, twin-tube heat exchanger is made...Ch. 11 - Consider a coupled shell-in-tube heat exchange...Ch. 11 - For health reasons, public spaces require the...Ch. 11 - A shell-and-tube heat exchanger (1 shell pass, 2...Ch. 11 - Saturated water vapor leaves a steam turbine at a...Ch. 11 - The human brain is especially sensitive to...Ch. 11 - Prob. 11.47PCh. 11 - A plate-tin heat exchanger is used to condense a...Ch. 11 - In a supercomputer, signal propagation delays...Ch. 11 - Untapped geothermal sites in the United States...Ch. 11 - A shell-and-tube heat exchanger consists of 135...Ch. 11 - An ocean thermal energy conversion system is...Ch. 11 - Prob. 11.55PCh. 11 - Prob. 11.56PCh. 11 - The chief engineer at a university that is...Ch. 11 - A shell-and-tube heat exchanger with one shell...Ch. 11 - Prob. 11.59PCh. 11 - Prob. 11.60PCh. 11 - Prob. 11.61PCh. 11 - Prob. 11.62PCh. 11 - A recuperator is a heat exchanger that heats air...Ch. 11 - Prob. 11.64PCh. 11 - Prob. 11.65PCh. 11 - A cross-flow heat exchanger consists of a bundle...Ch. 11 - Exhaust gas from a furnace is used to preheat the...Ch. 11 - Prob. 11.68PCh. 11 - A liquefied natural gas (LNG) regasification...Ch. 11 - Prob. 11.70PCh. 11 - A shell-and-tube heat exchanger consisting of...Ch. 11 - Prob. 11.73PCh. 11 - The power needed to overcome wind and friction...Ch. 11 - Prob. 11.75PCh. 11 - Consider a Rankine cycle with saturated steam...Ch. 11 - Consider the Rankine cycle of Problem 11.77,...Ch. 11 - Prob. 11.79PCh. 11 - Prob. 11.80PCh. 11 - Hot exhaust gases are used in a...Ch. 11 - Prob. 11.84PCh. 11 - Prob. 11.90PCh. 11 - Prob. 11S.1PCh. 11 - Prob. 11S.2PCh. 11 - Prob. 11S.3PCh. 11 - Solve Problem 11.15 using the LMTD method.Ch. 11 - Prob. 11S.5PCh. 11 - Prob. 11S.6PCh. 11 - Prob. 11S.8PCh. 11 - Prob. 11S.10PCh. 11 - Prob. 11S.11PCh. 11 - A cooling coil consists of a bank of aluminum...Ch. 11 - Prob. 11S.17P
Additional Engineering Textbook Solutions
Find more solutions based on key concepts
The wires each have a diameter of 12 in., length of 2 ft, and are made from 304 stainless steel. If P = 6 kip, ...
Mechanics of Materials
A piston/cylinder contains air at 150 psia, 1400 R with a volume of 1.75ft3 . The piston is pressed against the...
Fundamentals Of Thermodynamics
The support reactions. Also, draw the free body diagrams of Joints A, B, and C of the truss.
Engineering Mechanics: Statics & Dynamics (14th Edition)
Determine the components of reaction at hinges A and B it hinge B resists only forces in the x and y directions...
Engineering Mechanics: Statics
Why is laser-beam welding an attractive process for producing tailored blanks for sheet metal forming? For use ...
Degarmo's Materials And Processes In Manufacturing
If x = 8 m, vx = 8 m/s, and ax = 4 m/s2 when t = 2 s, determine the magnitude of the particles velocity and acc...
Engineering Mechanics: Dynamics (14th Edition)
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
- Water flowing in a long, aluminum lube is to be heated by air flowing perpendicular to the exterior of the tube. The ID of the tube is 1.85 cm, and its OD is 2.3 cm. The mass flow rate of the water through the tube is 0.65kg/s, and the temperature of the water in the lube averages 30C. The free-stream velocity and ambient temperature of the air are 10m/sand120C, respectively. Estimate the overall heat transfer coefficient for the heat exchanger using appropriate correlations from previous chapters. State all your assumptions.arrow_forward7.43 Liquid sodium is to be heated from 500 K to 600 K by passing it at a flow rate of 5.0 kg/s through a 5-cmID tube whose surface is maintained at 620 K. What length of tube is required?arrow_forwardDetermine the rate of heat transfer per meter length to a light oil flowing through a 2.5-cm-ID, 60-cm-long copper tube at a velocity of 0.03 m/s. The oil enters the tube at 16C, and the tube is heated by steam condensing on its outer surface at atmospheric pressure with a heat transfer coefficient of 11.3 kW/m K. The properties of the oil at various temperatures are listed in the following table: Temperature, T(C) 15 30 40 65 100 (kg/m3) 912 912 896 880 864 c(kJ/kgK) 1.80 1.84 1.925 2.0 2.135 k(W/mK) 0.133 0.133 0.131 0.129 0.128 (kg/ms) 0.089 0.0414 0.023 0.00786 0.0033 Pr 1204 573 338 122 55arrow_forward
- 6.3 Steam at 100 kPa and is flowing across a 5-cm- OD tube at a velocity of 6 m/s. Estimate the Nusselt number, the heat transfer coefficient, and the rate of heat transfer per meter length of pipe if the pipe is at .arrow_forwardfind: 1. The average heat transfer coefficient 2. The number of tubes needed to achieve the indicated heat transfer rate in the condenserarrow_forwardEngine oil (c_p=2100 J/(kg-K) ) is heated from 25 °C to 70 °C. The oil flows at a rate 0.5kgsec in a 2cm diameter thin walled copper tube. The oil is heated by condensing steam at 100oCon the outside of the 2cm tube in a counter-flow heat exchanger. The latent heat of vaporization for the steam is h_fg=2257kJkg. The overall heat transfer coefficient is U=1000WM2K, based on the 2cm diameter thin walled copper tube area. A) Find the overall heat transfer rate to the oil. B) Find the log-mean temperature difference.arrow_forward
- 5. Hot exhaust gases, which enter a finned-tube, cross-flow heat exchanger at 300 °C and leave at 100 °C, are used to heat pressurized water at a flow rate of 1 kg/s from 35 °C 125 °C. The specific heat of water at the average water temperature is 4197 J/kg. K. The overall heat transfer coefficient based on the gas-side surface area is Uh = 100 W/m².K. Determine the required gas-side surface area A₁ using the LMTD and & -NTU method.arrow_forwardA feed-water heater that supplies a boiler consists of a shell-and-tube heat exchanger with one shell and two tube passes. One hundred thin-walled tubes each have a diameter of 20 mm pass and a length (per pass) of 2 m. Under normal operating conditions water enters the tubes at 10 kg/s and 290 K and is heated by condensing saturated steam at 1 atm on the outer surface of the tubes. The convection coefficient of the saturated steam is 10,000 W/m2 K. Please use NTU method to determine the water outlet temperature. Hint: (1) please use the Dittus-Boelter correlation to determine the internal convection coefficient h;; (2) Assuming thin wall tubes and ignore the conduction resistance of the tube walls; (3) Please use Table A.6 to obtain all thermo-physical properties; (4) based on Table 11.3, choose an appropriate equation to obtain ɛ from NTU. TABLE 11.3 Heat Exchanger Effectiveness Relations [5] Flow Arrangement Relation 1- exp[-NTU(1 + C)] 1+C, Parallel ow (11.28a) 1- exp[-NTU(1 – C)]…arrow_forwardIn a chemical plant a solution of density 1100 kg/m' and specific heat capacity 4.6 kJ/kg K is to be heated from 65 "C to 100 "C; the required flow rate of solution is 11.8 kg/s. It is desired to use a tubular heat exchanger, the solution flowing at about 1.2 m/s in 25 mm bore iron tubes, and being heated by wet steam at 115°C. The length of the tubes must not exceed 3.5 m. Taking the inside and outside heat transfer coefficients as 5 and 10 kW/m K, and neglecting the thermal resistance of the tube wall, estimate the number of tubes and the number of tube passes required. 16.25arrow_forward
- How does a cross-flow heat exchanger differ from a counter-flow one? What is the difference between mixed and unmixed fluids in cross-flow?arrow_forward5. Hot exhaust gases, which enter a finned-tube, cross-flow heat exchanger at 300 °C and leave at 100 °C, are used to heat pressurized water at a flow rate of 1 kg/s from 35 °C 125 °C. The specific heat of water at the average water temperature is 4197 J/kg. K. The overall heat transfer coefficient based on the gas-side surface area is U₁ = 100 W/m².K. Determine the required gas-side surface area A₁ using the LMTD and & -NTU method.arrow_forwardA heat recovery device involves transferring energy from the hot flue gases passing through an annular region to pressurized water flowing through the inner tube of the annulus. The inner tube has inner and outer diameters of 24 and 30 mm and is connected by 8 struts to an insulated outer tube of 40-mm diameter. Each strut is 3 mm thick and is integrally fabricated with the inner tube from carbon steel (k = 50W/m-K). E1 = 3 mm D. Water Gas Consider conditions for which water at 300 K flows through the inner tube at 0.161 kg/s while flue gases at 800 K flow through the annulus, maintaining a convection coefficient of 100 W/m2-K on both the struts and the outer surface of the inner tube. What is the rate of heat transfer per unit length of tube from gas to the water? Use the Dittus-Boelter equation to obtain the water-side convection coefficient. Determine the rate of heat transfer per unit length of tube from gas to the water, in W/m. i W/m Physical Properties Mathematical Functionsarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning
Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license