Chapter 6 Fundamentals of Convection
Chapter 6
FUNDAMENTALS OF CONVECTION
Physical Mechanisms of Forced Convection
6-1C In forced convection, the fluid is forced to flow over a surface or in a tube by external means such
as a pump or a fan. In natural con
Chapter 5 Numerical Methods in Heat Conduction
Special Topic: Controlling the Numerical Error
5-96C The results obtained using a numerical method differ from the exact results obtained analytically
because the results obtained by a numerical method are ap
Chapter 5 Numerical Methods in Heat Conduction
5-84 A uranium plate initially at a uniform temperature is subjected to insulation on one side and
convection on the other. The transient finite difference formulation of this problem is to be obtained, and
t
Chapter 5 Numerical Methods in Heat Conduction
Transient Heat Conduction
5-63C The formulation of a transient heat conduction problem differs from that of a steady heat
conduction problem in that the transient problem involves an additional term that repr
Chapter 5 Numerical Methods in Heat Conduction
Two-Dimensional Steady Heat Conduction
5-43C For a medium in which the finite difference formulation of a general interior node is given in its
g l2
simplest form as Tleft + Ttop + Tright + Tbottom 4Tnode + n
Chapter 5 Numerical Methods in Heat Conduction
5-29 A plate is subjected to specified heat flux and specified temperature on one side, and no conditions
on the other. The finite difference formulation of this problem is to be obtained, and the temperature
Chapter 5 Numerical Methods in Heat Conduction
Chapter 5
NUMERICAL METHODS IN HEAT CONDUCTION
Why Numerical Methods
5-1C Analytical solution methods are limited to highly simplified problems in simple geometries. The
geometry must be such that its entire
Chapter 4 Transient Heat Conduction
4-118 Internal combustion engine valves are quenched in a large oil bath. The time it takes for the valve
temperature to drop to specified temperatures and the maximum heat transfer are to be determined.
Assumptions 1 T
Chapter 4 Transient Heat Conduction
Review Problems
4-105 Two large steel plates are stuck together because of the freezing of the water between the two
plates. Hot air is blown over the exposed surface of the plate on the top to melt the ice. The length
Chapter 4 Transient Heat Conduction
4-81 A cubic block and a cylindrical block are exposed to hot gases on all of their surfaces. The center
temperatures of each geometry in 10, 20, and 60 min are to be determined.
Assumptions 1 Heat conduction in the cub
Chapter 4 Transient Heat Conduction
Transient Heat Conduction in Multidimensional Systems
4-69C The product solution enables us to determine the dimensionless temperature of two- or threedimensional heat transfer problems as the product of dimensionless t
Chapter 4 Transient Heat Conduction
4-47 A hot dog is dropped into boiling water, and temperature measurements are taken at certain time
intervals. The thermal diffusivity and thermal conductivity of the hot dog and the convection heat
transfer coefficien
Chapter 4 Transient Heat Conduction
Transient Heat Conduction in Large Plane Walls, Long Cylinders, and Spheres
4-26C A cylinder whose diameter is small relative to its length can be treated as an infinitely long
cylinder. When the diameter and length of
Chapter 4 Transient Heat Conduction
Chapter 4
TRANSIENT HEAT CONDUCTION
Lumped System Analysis
4-1C In heat transfer analysis, some bodies are observed to behave like a "lump" whose entire body
temperature remains essentially uniform at all times during a
Chapter 3 Steady Heat Conduction
3-164 A circuit board houses electronic components on one side, dissipating a total of 15 W through the
backside of the board to the surrounding medium. The temperatures on the two sides of the circuit board
are to be dete
Chapter 3 Steady Heat Conduction
Review Problems
3-152E Steam is produced in copper tubes by heat transferred from another fluid condensing outside the
tubes at a high temperature. The rate of heat transfer per foot length of the tube when a 0.01 in thick
Chapter 3 Steady Heat Conduction
Heat Transfer In Common Configurations
3-120C Under steady conditions, the rate of heat transfer between two surfaces is expressed as
Q = Sk (T1 T2 ) where S is the conduction shape factor. It is related to the thermal res
Chapter 15 Steady Heat Conduction
Critical Radius Of Insulation
3-83C In a cylindrical pipe or a spherical shell, the additional insulation increases the conduction
resistance of insulation, but decreases the convection resistance of the surface because o
Chapter 15 Steady Heat Conduction
Heat Conduction in Cylinders and Spheres
3-64C When the diameter of cylinder is very small compared to its length, it can be treated as an
indefinitely long cylinder. Cylindrical rods can also be treated as being infinite
Chapter 15 Steady Heat Conduction
Thermal Contact Resistance
3-39C The resistance that an interface offers to heat transfer per unit interface area is called thermal
contact resistance , Rc . The inverse of thermal contact resistance is called the thermal
Chapter 3 Steady Heat Conduction
Chapter 3
STEADY HEAT CONDUCTION
Steady Heat Conduction In Plane Walls
3-1C (a) If the lateral surfaces of the rod are insulated, the heat transfer surface area of the cylindrical rod
is the bottom or the top surface area
Chapter 2 Heat Conduction Equation
2-126 A spherical liquid nitrogen container is subjected to specified temperature on the inner surface and
convection on the outer surface. The mathematical formulation, the variation of temperature, and the
rate of evap
Chapter 2 Heat Conduction Equation
Variable Thermal Conductivity
2-94C During steady one-dimensional heat conduction in a plane wall, long cylinder, and sphere with
constant thermal conductivity and no heat generation, the temperature in only the plane wa
Chapter 2 Heat Conduction Equation
2-68 A compressed air pipe is subjected to uniform heat flux on the outer surface and convection on the
inner surface. The mathematical formulation, the variation of temperature in the pipe, and the surface
temperatures
Chapter 2 Heat Conduction Equation
Solution of Steady One-Dimensional Heat Conduction Problems
2-52C Yes, this claim is reasonable since in the absence of any heat generation the rate of heat transfer
through a plain wall in steady operation must be const
Chapter 2 Heat Conduction Equation
Chapter 2
HEAT CONDUCTION EQUATION
Introduction
2-1C Heat transfer is a vector quantity since it has direction as well as magnitude. Therefore, we must
specify both direction and magnitude in order to describe heat trans
Chapter 1 Basics of Heat Transfer
Review Problems
1-121 Cold water is to be heated in a 1200-W teapot. The time needed to heat the water is to be
determined.
Assumptions 1 Steady operating conditions exist. 2 Thermal properties of the teapot and the water
Chapter 1 Basics of Heat Transfer
1-87E A 200-ft long section of a steam pipe passes through an open space at a specified temperature. The
rate of heat loss from the steam pipe and the annual cost of this energy lost are to be determined.
Assumptions 1 St
Chapter 1 Basics of Heat Transfer
Heat Transfer Mechanisms
1-44C The thermal conductivity of a material is the rate of heat transfer through a unit thickness of the
material per unit area and per unit temperature difference. The thermal conductivity of a
Chapter 1 Basics of Heat Transfer
Chapter 1
BASICS OF HEAT TRANSFER
Thermodynamics and Heat Transfer
1-1C Thermodynamics deals with the amount of heat transfer as a system undergoes a process from one
equilibrium state to another. Heat transfer, on the ot