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 7CP
In order to size the compressor of a new refrigerator, we wish to determine the rate of heat transfer from the kitchen air into the refrigerated space through the walls, door and the top and bottom sections of the refrigerator. In your analysis, would you treat this as a transient or as a steady-state heat transfer problem? Also, would you consider the heat transfer to be one-dimensional or multidimensional? Explain.
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- Steam at 280C flows in a stainless steel pipe k = 15 W/m.K whose inner and outer diameter are 5cm and 5.5cm, respectively. The pipe covered with 3cm glass wool insulation k = 0.038 W/m.K. Heat is lost to the surroundings at 5C by natural convection and radiation, with a combined natural convection and radiation heat transfer coefficient of 22W/m2.K. Taking the heat transfer coefficient inside the pipe to be 80W/m2.K, determine the rate of heat loss from the steam per unit length of the pipe. Also determine the temperature drop across the pipe shell and the insulation
Steam at 280° C flows in a stainless steel pipe (k = 15 W/m⋅K) whose inner and outer diameters are 5 cm and 5.5 cm, respectively. The pipe is covered with 3-cm-thick glass wool insulation (k = 0.038 W/m⋅K). Heat is lost to the surroundings at 5° C by natural convection and radiation, with a combined natural convection and radiation heat transfer coefficient of 22 W/ m2⋅K.Taking the heat transfer coefficient inside the pipe to be 80 W/ m2⋅K.Determine the rate of heat loss from the steam per unit length of the pipe and Determine the temperature decrease between the inner pipe surface and the outer insulation surface.
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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