Table 7 gives values of Nusselt number (Nu) as a function of the Rayleigh number  and  based on the average heat transfer measurements of the present study.
It is of interest to compare the result obtained in Table 7 with correlations and data available in the literature. This comparison for buoyancy- driven flows from flush as well as protruding surfaces is presented below.
Isothermal vertical flat plate
where  The minimum and the maximum Nusselt numbers computed using this equation for the limiting Rayleigh numbers in table 7 are 4.07 and 6.11, respectively.
Constant heat flux vertical surface
where  The minimum and maximum Nusselt numbers from this correlation are 5.28 and 7.86, respectively.
Protruding block on a vertical surface, aspect ratio=2.5,
For  , Nu varies from 10 to 12.
Fully developed flow foe an array of protruding blocks, aspect ratio = 2
For  Nu varies from 5 to 8.
Cuboid Models for an isothermal block of dimensions  .
Table 7: Average Nusselt Number as a Function of Rayleigh Number; 
|
2.48 |
3.35 |
389 |
9.29 |
13.3 |
14.9 |
17.3 |
|
8.7 |
12.7 |
15.1 |
28.7 |
44.3 |
53.0 |
63.6 |
|
13.2 |
13.5 |
13.8 |
14.7 |
16.0 |
17.1 |
17.6 |
|
