Page 155 - Mechanical Engineers' Handbook (Volume 4)

Mechanical Engineers’ Handbook: Energy and Power, Volume 4, Third Edition.

Edited by Myer Kutz

Copyright  2006 by John Wiley & Sons, Inc.

CHAPTER 5
HEAT-TRANSFER FUNDAMENTALS
G. P. Peterson
Rensselaer Polytechnic Institute
Troy, New York
1 CONDUCTION HEAT TRANSFER 146 3 RADIATION HEAT TRANSFER 177
1.1 Thermal Conductivity 147 3.1 Blackbody Radiation 178
1.2 One-Dimensional Steady-State 3.2 Radiation Properties 180
Heat Conduction 148 3.3 Configuration Factor 186
1.3 Two-Dimensional Steady-State 3.4 Radiative Exchange among
Heat Conduction 155 Diffuse-Gray Surfaces in
1.4 Heat Conduction with Convection an Enclosure 190
Heat Transfer on the Boundaries 156 3.5 Thermal Radiation Properties
1.5 Transient Heat Conduction 160 of Gases 193
1.6 Conduction at the Microscale 164
4 BOILING AND CONDENSATION
2 CONVECTION HEAT TRANSFER 167 HEAT TRANSFER 197
2.1 Forced Convection—Internal 4.1 Boiling 198
Flow 167 4.2 Condensation 201
2.2 Forced Convection—External 4.3 Heat Pipes 203
Flow 169
2.3 Free Convection 174 REFERENCES 209
2.4 The Log-Mean Temperature
Difference 176 BIBLIOGRAPHY 210

SYMBOLS AND UNITS
A area of heat transfer
Bi Biot Number, hL/k, dimensionless
C circumference, m, constant defined in text
C p specific heat under constant pressure, J/kg K
D diameter, m
e emissive power, W/m 2
f drag coefficient, dimensionless
F cross flow correction factor, dimensionless
F i-j configuration factor from surface i to surface j, dimensionless
2
2
Fo Fourier Number, tA /V , dimensionless
F o- T radiation function, dimensionless
2
2
G irradiation, W/m ; mass velocity, kg/m s
g local gravitational acceleration, 9.8 m/s 2
g c proportionality constant, 1 kg m/N s 2
Gr Grashof number, gL T/v dimensionless
3
2
h convection heat transfer coefficient, equals q/A T, W/m K
2
h fg heat of vaporization, J/kg
J radiosity, W/m 2
k thermal conductivity, W/m K
K wick permeability, m 2
L length, m
Ma Mach number, dimensionless
N screen mesh number, m 1
144