Effect of cylinder Orientation on free convective heat transfer in glycerol

Abstract

The effect of cylinder orientation on the free convective heat transfer in
glycerol is studied for the Rayleigh numbers, 10-6 ≤ Ra ≤ 109 and Prandtl
number, Pr = 11630. While varying the orientation of the cylinder,
correlations due to Churchill & Chu, Raithby & Holland, Kuehn & Goldstein,
Fand et al, Jaluria and Neeta et al are used to evaluate the free convective
Nusselt number as a function of Rayleigh number at orientations of 00, 100,
200, 300, 400, 500, 600, 700, 800 and 900. Additionally, the Rayleigh number
is kept fixed at three regimes of 10-6, 100 and 106 and the free Nusselt
number is evaluated as a function of the cylinder orientation. At maximum
orientation (θ = 900) an increase of 114% in Nusselt number is observed for
Kuehn & Goldstein correlation