Heat and Mass Transfer: Fundamentals and Applications
5th Edition
ISBN: 9780073398181
Author: Yunus A. Cengel Dr., Afshin J. Ghajar
Publisher: McGraw-Hill Education
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Chapter 2, Problem 166P
The thermal conductivity of a solid depends upon the solid’s temperature as
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Shape Factor Conduction Problem
A cylindrical pipeline that is used for the transport of crude oil is buried in the soil horizontally
such that its centerline is 1.5 m (z) below the surface. The pipe has the outer diameter of 0.5 m
(D) and is coated with a 100 mm thick layer of glass insulation on the outside. Assume that
heated oil at 120 °C flows through the pipe and the soil surface temperature is at 0 °C (T2). The
soil thermal conductivity is known as 0.5 W/m-K, and the glass insulation thermal conductivity
is known as 0.07 W/m-K. What is the rate of heat loss per unit length of the pipe (W/m)?
Soil
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The figure shows the cross section of a wall made of three layers. The thicknesses of the layers are L1. L2 =0.500 L1. and L3 = 0.350 L1.
The thermal conductivities are k1, k2 = 0.800 k1, and k3 = 0.680 k1. The temperatures at the left and right sides of the wall are TH = 20 °C
and Tc = -10 °C, respectively. Thermal conduction is steady.
(a) What is the temperature difference AT2 across layer 2 (between the left and right sides of the layer)?
If k2 were, instead, equal to 1.100 k1,
(b) would the rate at which energy is conducted through the wall be greater than, less than, or the same as previously,
and
(c) what would be the value of AT2?
k1
ko k3
TH
Tc
L1
L9 L3
(a) AT2 =
i
(b)
(c) AT2= i
3. Thermal conductivity of a substance is measured as k = k, TIT, . Find an
average value for thermal conductivity in the temperature range of T1 and T2.
[Ans. = (k, /272 xT} 2 – T}/2) (T2 – T;) 1|
Chapter 2 Solutions
Heat and Mass Transfer: Fundamentals and Applications
Ch. 2 - How does transient heat transfer from steady heat...Ch. 2 - Is heat transfer a scalar or a vector quantity?...Ch. 2 - Does a hear flux vector at a point P on an...Ch. 2 - From a heat transfer point of view, what is the...Ch. 2 - What is heat generation in a solid? Give examples.Ch. 2 - Heat generation is also referred to as energy...Ch. 2 - In order to size the compressor of a new...Ch. 2 - In order to determine the size of the heating...Ch. 2 - Consider a round potato being baked in an oven....Ch. 2 - Consider an egg being cooked in boiling water in a...
Ch. 2 - Prob. 11CPCh. 2 - Consider the cooking process of a roast beef in an...Ch. 2 - Consider heat loss from a 200-L cylindrical hot...Ch. 2 - Consider a cold canned drink left on a dinner...Ch. 2 - Heat flux meters use a very sensitive device know...Ch. 2 - Consider a large 3-cm-thick stainless steel plate...Ch. 2 - In a nuclear reactor, heat is generated uniformly...Ch. 2 - Prob. 18PCh. 2 - Prob. 19EPCh. 2 - Writer down the one-dimensional transient heat...Ch. 2 - Writer down the one-dimensional transient heat...Ch. 2 - Starting with an energy balance on rectangular...Ch. 2 - Prob. 23PCh. 2 - Prob. 24PCh. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Starting with an energy balance on a volume...Ch. 2 - Prob. 33PCh. 2 - Prob. 34PCh. 2 - What is a boundary condition? How many boundary...Ch. 2 - What is an initial condition? How many initial...Ch. 2 - What is a thermal symmetry boundary condition? How...Ch. 2 - How is the boundary condition on an insulated...Ch. 2 - It is claimed that the temperature profile in a...Ch. 2 - Why do we try to avoid the radiation boundary...Ch. 2 - Consider an aluminum pan used to cook stew on top...Ch. 2 - Prob. 42PCh. 2 - Prob. 43PCh. 2 - Heat is generated in a long wire of radius ro at a...Ch. 2 - Consider a long pipe of inner radius r1, Outer...Ch. 2 - A 2-kW resistance heater wire whose thermal...Ch. 2 - Prob. 47PCh. 2 - Prob. 48PCh. 2 - Consider a spherical shell of inner radius r1,...Ch. 2 - A container consists of two spherical layers, A...Ch. 2 - A spherical metal ball of radius ro is heated in...Ch. 2 - Prob. 52PCh. 2 - It is stated that the temperature in a plane wall...Ch. 2 - Consider one-dimensional heat conduction through a...Ch. 2 - Consider a solid cylindrical rod whose side...Ch. 2 - Consider a solid cylindrical rod whose ends are...Ch. 2 - Prob. 57PCh. 2 - Prob. 58PCh. 2 - Prob. 59PCh. 2 - Consider a 20-cm-thick concrete plane wall...Ch. 2 - Prob. 61PCh. 2 - Prob. 62PCh. 2 - Prob. 63PCh. 2 - Prob. 64PCh. 2 - Prob. 65EPCh. 2 - Prob. 66PCh. 2 - Consider a chilled-water pipe of length L, inner...Ch. 2 - Prob. 68EPCh. 2 - Prob. 69PCh. 2 - Prob. 70PCh. 2 - Prob. 71PCh. 2 - Prob. 72PCh. 2 - Prob. 73PCh. 2 - Prob. 74PCh. 2 - Prob. 75PCh. 2 - Prob. 76PCh. 2 - Prob. 77PCh. 2 - Prob. 78CPCh. 2 - Does heat generation in a solid violate the first...Ch. 2 - Prob. 80CPCh. 2 - Prob. 81CPCh. 2 - Prob. 82CPCh. 2 - Prob. 83PCh. 2 - Prob. 84PCh. 2 - Consider a large 3-cm thick stainless steel plate...Ch. 2 - Prob. 86PCh. 2 - Prob. 87EPCh. 2 - Prob. 88PCh. 2 - Prob. 89PCh. 2 - Prob. 90PCh. 2 - Heat is generated uniformly at a rate of 3 kW per...Ch. 2 - Prob. 92PCh. 2 - Prob. 93PCh. 2 - Prob. 94PCh. 2 - Prob. 95PCh. 2 - Prob. 96PCh. 2 - Prob. 97PCh. 2 - Prob. 98PCh. 2 - Prob. 99PCh. 2 - Prob. 100PCh. 2 - Prob. 101PCh. 2 - Prob. 102PCh. 2 - Prob. 103PCh. 2 - Prob. 104CPCh. 2 - When the thermal conductivity of a medium varies...Ch. 2 - The temperature of a plane wall during steady...Ch. 2 - Consider steady one-dimensional heat conduction in...Ch. 2 - Prob. 108CPCh. 2 - Prob. 109PCh. 2 - Prob. 110PCh. 2 - Prob. 111PCh. 2 - Consider a plane wall of thickness L whose thermal...Ch. 2 - Prob. 113PCh. 2 - Prob. 114PCh. 2 - A pipe is used for transporting boiling water in...Ch. 2 - Prob. 116PCh. 2 - Prob. 117PCh. 2 - Consider a spherical shell of inner radius r1 and...Ch. 2 - Prob. 119PCh. 2 - A spherical tank is filled with ice slurry, where...Ch. 2 - Prob. 121CPCh. 2 - Prob. 122CPCh. 2 - Can a differential equation involve more than one...Ch. 2 - Prob. 124CPCh. 2 - Prob. 125CPCh. 2 - Prob. 126CPCh. 2 - Prob. 127CPCh. 2 - How is integation related to derivation?Ch. 2 - Prob. 129CPCh. 2 - Prob. 130CPCh. 2 - How is the order of a differential equation...Ch. 2 - How do you distinguish a linear differential...Ch. 2 - How do you recognize a linear homogeneous...Ch. 2 - How do differential equations with constant...Ch. 2 - What kinds of differential equations can be solved...Ch. 2 - Consider a third-order linear and homogeneous...Ch. 2 - A large plane wall, with a thickness L and a...Ch. 2 - Prob. 138PCh. 2 - Prob. 139EPCh. 2 - A spherical vessel has an inner radius r1 and an...Ch. 2 - Consider a short cylinder of radius r0 and height...Ch. 2 - Prob. 142PCh. 2 - Prob. 143PCh. 2 - Consider a 20-cm-thick large concrete plane wall...Ch. 2 - Prob. 145PCh. 2 - Prob. 146PCh. 2 - Prob. 147EPCh. 2 - Prob. 148PCh. 2 - In a manufacturing plant, a quench hardening...Ch. 2 - Consider a water pipe of length L=17m, inner...Ch. 2 - Prob. 151PCh. 2 - Consider a spherical reactor of 5-cm diameter...Ch. 2 - Consider a cylindrical sheel of length L, inner...Ch. 2 - A pipe is used for transporting boiling water in...Ch. 2 - A metal spherical tank is filled with chemicals...Ch. 2 - The heat conduction equation in a medium is given...Ch. 2 - Consider a medium in which the heat conduction...Ch. 2 - Consider a large plane wall of thicness L, thermal...Ch. 2 - A solar heat flux qs is incident on a sidewalk...Ch. 2 - A plane wall of thickness L is subjected to...Ch. 2 - Consider steady one-dimensional heat conduction...Ch. 2 - The conduction eqution boundary condition for an...Ch. 2 - Prob. 163PCh. 2 - Prob. 164PCh. 2 - The temperatures at the inner and outer surfaces...Ch. 2 - The thermal conductivity of a solid depends upon...Ch. 2 - Prob. 167PCh. 2 - Prob. 168PCh. 2 - Prob. 169PCh. 2 - Prob. 170PCh. 2 - Prob. 171PCh. 2 - Write essay on heat generation in nuc1e e1 rods....Ch. 2 - Write an interactive computer program to calculate...Ch. 2 - Prob. 174P
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