Natural convection in a square enclosure with heated vertical walls and temperature-dependent conductivity and viscosity was simulated for Prandtl numbers ranging from 0.01 to 1.0 and Ra ≤ 106. Although the variable properties produced observable changes in the the temperatures and velocities, the overall heat transfer, as represented by the Nusselt number, was found to be unaffected and was accurately correlated in terms of the Rayleigh and Prandtl numbers using Nu=0.185Ra00.278Pr00.089 with properties evaluated at the average temperature. This correlation applies to both isothermal and constant heat flux hot walls.

Issue Section:
Natural and Mixed Convection
Keywords:
Analog Techniques, Instrumentation, Measurement Techniques
Topics:
Natural convection, Temperature, Electrical conductivity, Heat flux, Heat transfer, Instrumentation, Thermal conductivity, Viscosity
1.
ANSYS User’s Manual, 1995, SAS IP.
2.
Booker
 
J. R.
,
1976
, “
Thermal Convection With Strongly Temperature-Dependent Viscosity
,
J. Fluid Mechanics
, Vol.
76
, pp.
741
–
754
.
3.
Chenoweth
 
D. R.
, and
Paolucci
 
S.
,
1986
, “
Natural Convection in an Enclosed Vertical Air Layer
,”
J. Fluid Mechanics
, Vol.
169
, pp.
173
–
210
.
4.
Hyun
 
J. M.
, and
Lee
 
J. W.
,
1988
, “
Transient Natural Convection in a Square Cavity of a Fluid With Temperature-Dependent Viscosity
,”
Int. J. Heat and Fluid Flow
, Vol.
9
, pp.
278
–
285
.
5.
Incropera, F. P., and DeWitt, D. P., 1996, Introduction to Heat Transfer, John Wiley and Sons, New York.
6.
Jacob, M., 1949, Heat Transfer, Vol. 1, John Wiley and Sons, New York.
7.
Jones
 
I. P.
, and
de Vahl Davis
 
G.
,
1983
, “
Natural Convection in a Square Cavity: A Comparison Exercise
,”
Int. J. Num. Methods in Fluids
, Vol.
3
, pp.
227
–
248
.
8.
Mallison
 
G. D.
, and
de Vahl Davis
 
G.
,
1977
, “
Three-Dimensional Natural Convection in a Box: A Numerical Study
,”
J. Fluid Mechanics
, Vol.
83
, pp.
1
–
31
.
9.
Markatos
 
N. C.
, and
Pericleous
 
K. A.
,
1984
, “
Laminar and Turbulent Natural Convection in an Enclosed Cavity
,”
Int. J. Heat Mass Transfer
, Vol.
27
, No.
5
, pp.
755
–
772
.
10.
Ralston, A., A., 1978, First Course in Numerical Analysis, McGraw-Hill, New York.
11.
Viskanta
 
R.
,
Kim
 
D. M.
, and
Gau
 
C.
,
1986
, “
Three-Dimensional Natural Convection Heat Transfer in a Liquid Metal in a Cavity
,”
Int. J. Heat and Mass Transfer
, Vol.
29
, pp.
475
–
484
.
12.
Yamasaki
 
T.
, and
Irvine
 
T. F.
,
1984
, “
Laminar Free Convection in a Vertical Tube with Temperature-Dependent Viscosity
,”
Int. J. Heat and Mass Transfer
, Vol.
27
, pp.
1613
–
1621
.
This content is only available via PDF.
Copyright © 1999
 by The American Society of Mechanical Engineers
You do not currently have access to this content.