Chapter 9 Natural Convection
Review Problems 9-94E A small cylindrical resistor mounted on the lower part of a vertical circuit board. The approximate surface temperature of the resistor is to be determined. Assumptions 1 Steady operating conditions exist

Chapter 12 Radiation Heat Transfer
Review Problems 12-88 The temperature of air in a duct is measured by a thermocouple. The radiation effect on the temperature measurement is to be quantified, and the actual air temperature is to be determined. Assumptio

Chap 13 Heat Exchangers
Chapter 13 HEAT EXCHANGERS
Types of Heat Exchangers
13-1C Heat exchangers are classified according to the flow type as parallel flow, counter flow, and crossflow arrangement. In parallel flow, both the hot and cold fluids enter the

Chap 15 Heat Exchangers
The Log Mean Temperature Difference Method
13-32C Tlm is called the log mean temperature difference, and is expressed as
Tlm T1 T2 ln( T1 / T2 )
where
T1 = Th,in - Tc,in
T = Th,in - Tc,out
T2 = Th,out - Tc,out
T2 = Th,out - Tc,in
f

Chap 15 Heat Exchangers 13-54 Glycerin is heated by ethylene glycol in a thin-walled double-pipe parallel-flow heat exchanger. The rate of heat transfer, the outlet temperature of the glycerin, and the mass flow rate of the ethylene glycol are to be deter

Chap 13 Heat Exchangers
The Effectiveness-NTU Method
13-68C When the heat transfer surface area A of the heat exchanger is known, but the outlet temperatures are not, the effectiveness-NTU method is definitely preferred.
13-69C The effectiveness of a heat

Chap 13 Heat Exchangers 13-95 Cold water is heated by hot water in a heat exchanger. The net rate of heat transfer and the heat transfer surface area of the heat exchanger are to be determined. Assumptions 1 Steady operating conditions exist. 2 The heat e

Chap 13 Heat Exchangers
Review Problems
13-111 Hot oil is cooled by water in a multi-pass shell-and-tube heat exchanger. The overall heat transfer coefficient based on the inner surface is to be determined. Assumptions 1 Water flow is fully developed. 2 P

Chapter 14 Mass Transfer
Chapter 14 MASS TRANSFER
Mass Transfer and Analogy Between Heat and Mass Transfer
14-1C Bulk fluid flow refers to the transportation of a fluid on a macroscopic level from one location to another in a flow section by a mover such

Chapter 14 Mass Transfer
Steady Mass Diffusion Through a Wall
14-42C The relations for steady one-dimensional heat conduction and mass diffusion through a plane wall are expressed as follows: Heat conduction: Mass diffusion:
Qcond
mdiff,A,wall
kA
T1 T2

Chapter 14 Mass Transfer
Diffusion in a Moving Medium
14-74C The mass-average velocity of a medium at some location is the average velocity of the mass at that location relative to an external reference point. It is the velocity that would be measured by

Chapter 12 Radiation Heat Transfer
Special Topic: Heat Transfer from the Human Body
12-74C Yes, roughly one-third of the metabolic heat generated by a person who is resting or doing light work is dissipated to the environment by convection, one-third by e

Chapter 12 Radiation Heat Transfer 12-41 A circular grill is considered. The bottom of the grill is covered with hot coal bricks, while the wire mesh on top of the grill is covered with steaks. The initial rate of radiation heat transfer from coal bricks

Chapter 9 Natural Convection 9-103E The components of an electronic device located in a horizontal duct of rectangular cross section is cooled by forced air. The heat transfer from the outer surfaces of the duct by natural convection and the average tempe

Chapter 10 Boiling and Condensation
Chapter 10 BOILING AND CONDENSATION
Boiling Heat Transfer
10-1C Boiling is the liquid-to-vapor phase change process that occurs at a solid-liquid interface when the surface is heated above the saturation temperature of

Chapter 10 Boiling and Condensation 10-21 Water is boiled at 1 atm pressure and thus at a saturation (or boiling) temperature of Tsat = 100 C by a horizontal nickel plated copper heating element. The maximum (critical) heat flux and the temperature jump o

Chapter 10 Boiling and Condensation
Condensation Heat Transfer
10-34C Condensation is a vapor-to-liquid phase change process. It occurs when the temperature of a vapor is reduced below its saturation temperature Tsat. This is usually done by bringing the

Chapter 10 Boiling and Condensation Review Problems 10-72 Steam at a saturation temperature of Tsat = 40 C condenses on the outside of a thin horizontal tube. Heat is transferred to the cooling water that enters the tube at 25 C and exits at 35 C. The rat

Chapter 11 Fundamentals of Thermal Radiation
Chapter 11 FUNDAMENTALS OF THERMAL RADIATION
Electromagnetic and Thermal Radiation
11-1C Electromagnetic waves are caused by accelerated charges or changing electric currents giving rise to electric and magneti

Chapter 11 Fundamentals of Thermal Radiation
Atmospheric and Solar Radiation
11-50C The solar constant represents the rate at which solar energy is incident on a surface normal to sun's rays at the outer edge of the atmosphere when the earth is at its mea

Chapter 15 Cooling of Electronic Equipment 15-140 A multilayer circuit board consisting of four layers of copper and three layers of glass-epoxy sandwiched together is considered. The magnitude and location of the maximum temperature that occurs in the PC

Chapter 12 Radiation Heat Transfer
Chapter 12 RADIATION HEAT TRANSFER
View Factors
12-1C The view factor Fi
j
represents the fraction of the radiation leaving surface i that strikes surface j
directly. The view factor from a surface to itself is non-zero

Chapter 14 Mass Transfer 14-107 A raindrop is falling freely in atmospheric air. The terminal velocity of the raindrop at which the drag force equals the weight of the drop and the average mass transfer coefficient are to be determined. Assumptions 1 The

Chapter 14 Mass Transfer 14-119 A person is standing outdoors in windy weather. The rates of heat loss from the head by radiation, forced convection, and evaporation are to be determined for the cases of the head being wet and dry. Assumptions 1 The low m

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
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 2-126 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 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