Introduction to Heat Transfer
6th Edition
ISBN: 9780470501962
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 4, Problem 4.29P
Hot water is transported from a cogeneration power station to commercial and industrial users through steel pipes of diameter
- If the inlet temperature of water flowing through the pipe is
- If the difference between the inlet and outlet temperatures of water flowing through a 100-m-long pipe is not to exceed 5°C, estimate the minimum allowable flow rate
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Q1 (a) The temperature at the inner and outer surfaces of a boiler wall made of 25 mm
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(AT)overall
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ΣRth
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1. A thermodynamic analysis of a proposed Brayton cycle gas turbine yields P=
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Question 3
Steam in a heating system flows through tubes whose outer diameter is 5 cm and whose walls are
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Chapter 4 Solutions
Introduction to Heat Transfer
Ch. 4 - In the method of separation of variables (Section...Ch. 4 - A two-dimensional rectangular plate is subjected...Ch. 4 - Consider the two-dimensional rectangular plate...Ch. 4 - A two-dimensional rectangular plate is subjected...Ch. 4 - Prob. 4.5PCh. 4 - Prob. 4.6PCh. 4 - Free convection heat transfer is sometimes...Ch. 4 - Prob. 4.8PCh. 4 - Radioactive wastes are temporarily stored in a...Ch. 4 - Based on the dimensionless conduction heat rates...
Ch. 4 - Prob. 4.11PCh. 4 - A two-dimensional object is subjected to...Ch. 4 - Prob. 4.13PCh. 4 - Two parallel pipelines spaced 0.5 m apart are...Ch. 4 - A small water droplet of diameter D=100m and...Ch. 4 - Prob. 4.16PCh. 4 - Pressurized steam at 450 K flows through a long,...Ch. 4 - Prob. 4.19PCh. 4 - A furnace of cubical shape, with external...Ch. 4 - Prob. 4.21PCh. 4 - Prob. 4.22PCh. 4 - A pipeline, used for the transport of crude oil,...Ch. 4 - A long power transmission cable is buried at a...Ch. 4 - Prob. 4.25PCh. 4 - A cubical glass melting furnace has exterior...Ch. 4 - Prob. 4.27PCh. 4 - An aluminum heat sink k=240W/mK, used to coolan...Ch. 4 - Hot water is transported from a cogeneration power...Ch. 4 - Prob. 4.30PCh. 4 - Prob. 4.31PCh. 4 - Prob. 4.32PCh. 4 - An igloo is built in the shape of a hemisphere,...Ch. 4 - Consider the thin integrated circuit (chip) of...Ch. 4 - Prob. 4.35PCh. 4 - The elemental unit of an air heater consists of a...Ch. 4 - Prob. 4.37PCh. 4 - Prob. 4.38PCh. 4 - Prob. 4.39PCh. 4 - Prob. 4.40PCh. 4 - Prob. 4.41PCh. 4 - Determine expressions for...Ch. 4 - Prob. 4.43PCh. 4 - Prob. 4.44PCh. 4 - Prob. 4.45PCh. 4 - Derive the nodal finite-difference equations for...Ch. 4 - Prob. 4.47PCh. 4 - Prob. 4.48PCh. 4 - Consider a one-dimensional fin of uniform...Ch. 4 - Prob. 4.50PCh. 4 - Prob. 4.52PCh. 4 - Prob. 4.53PCh. 4 - Prob. 4.54PCh. 4 - Prob. 4.55PCh. 4 - Prob. 4.56PCh. 4 - Steady-state temperatures at selected nodal points...Ch. 4 - Prob. 4.58PCh. 4 - Prob. 4.60PCh. 4 - The steady-state temperatures C associated with...Ch. 4 - A steady-state, finite-difference analysis has...Ch. 4 - Prob. 4.64PCh. 4 - Consider a long bar of square cross section (0.8 m...Ch. 4 - Prob. 4.66PCh. 4 - Prob. 4.67PCh. 4 - Prob. 4.68PCh. 4 - Prob. 4.69PCh. 4 - Consider Problem 4.69. An engineer desires to...Ch. 4 - Consider using the experimental methodology of...Ch. 4 - Prob. 4.72PCh. 4 - Prob. 4.73PCh. 4 - Prob. 4.74PCh. 4 - Prob. 4.75PCh. 4 - Prob. 4.76PCh. 4 - Prob. 4.77PCh. 4 - Prob. 4.78PCh. 4 - Prob. 4.79PCh. 4 - Prob. 4.80PCh. 4 - Spheres A and B arc initially at 800 K, and they...Ch. 4 - Spheres of 40-mm diameter heated to a uniform...Ch. 4 - To determine which parts of a spiders brain are...Ch. 4 - Prob. 4.84P
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- 5. Consider a carton of milk that is refrigerated at a temperature of Tm = 5 °C. The kitchen temperature on a hot summer day is T- -30 °C. If the four sides of the carton are of height and width L = 200 mm and w= 100 mm, respectively, determine the heat transferred to the milk carton as it sits on the kitchen counter for durations of t=10 s, 60 s, and 300 s before it is returned to the refrigerator. The convection coefficient associated with natural convection on the sides of the carton is h = 10 W/m²K. The surface emissivity is 0.90. Assume the milk carton temperature remains at 5 °C during the process. Your parents have taught you the importance of refrigerating certain foods from the food safety perspective. Comment on the importance of quickly returning the milk carton to the refrigerator from an energy conservation point of view.arrow_forwardExample 4: A wall has the following specifications as shown in figure below: Height = 3 m. Width = 5m k (bricks)=0.72 W/m · °C k (plaster) = 0.22 W/m · °C k (foam) =0.026 W/m · °C. The indoor and the outdoor temperatures are 20°C and -10°C. convection heat transfer coefficients on the inner and the outer sides are h1 = 10 W/m2·°C and h2 = 25 W/m2· °C, respectively. Determine the rate of heat transfer through the wall.arrow_forwardA cylindrical reactor made of copper with a radius of a= r=5mm has a heat conduction coefficient of k=386 W/moC, and there is heat generation at e ̇= (q ) ̇= 4x10^8 W/m3 inside this reactor. The cylindrical reactor convection heat transfer coefficient is h=2000 W/m0C and 〖T_(ambient= ) T〗_∞= 30 oC by convection, it cools down from the reactor surface to the center. According to the given boundary conditions a)Find the reactor surface temperature and the temperature T(a) at r=a. (VARIABLES: r=1-10mm, T_∞= 0-100oC) b) q(a) =((q ) ̇ * a )/ 2 = (e ̇ * a )/ 2 then find the heat flux amount in kW/m2arrow_forward
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