Nusselt number, object to gas

Symbol
$\mathrm{Nu}_{og}$
Formulae
$\frac{0.797 \left(\frac{D_{di}}{D_{o}}\right)^{0.505} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{0.077}}{\left(\frac{L_{d}}{\delta _{d}}\right)^{0.052}}$Riser closed at both ends, $Ra < 363 \cdot K^{0.25}G^{0.76}$ (Anders)
$\frac{0.188 \left(\frac{D_{di}}{D_{o}}\right)^{0.442} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{0.322}}{\left(\frac{L_{d}}{\delta _{d}}\right)^{0.238}}$Riser closed at both ends, $363 \cdot K^{0.25}G^{0.76} < Ra < 2.3 \cdot 10^6$ (Anders)
$0.1103 \mathrm{Gr}_{og} \mathrm{Pr}_{gas}$Riser open at both ends, $Gr \cdot Pr < 10$ (Anders)
$0.62 \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{0.25}$Riser open at both ends, otherwise (Anders)
$c_{\mathrm{Nu}_{r}} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{n_{\mathrm{Nu}_{r}}}$Riser open at top and closed at bottom (Anders)
$c_{\mathrm{Nu}_{r}} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{n_{\mathrm{Nu}_{r}}}$Riser closed at both ends (Hartlein & Black)
$0.986 \mathrm{Ra}_{gas}^{0.177}$Riser open at both ends, 133 ≤ $Ra$ ≤ 7000 (Hartlein & Black IIa)
$c_{\mathrm{Nu}_{r}} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{n_{\mathrm{Nu}_{r}}}$Riser open at both ends, $Ra$ > 7000 (Hartlein & Black IIb)
$c_{\mathrm{Nu}_{r}} \left(\mathrm{Gr}_{og} \mathrm{Pr}_{gas}\right)^{n_{\mathrm{Nu}_{r}}}$Riser open at top and closed at bottom (Hartlein & Black)
Related
$c_{\mathrm{Nu}_{r}}$
$D_{o}$
$n_{\mathrm{Nu}_{r}}$
$\mathrm{Pr}_{gas}$
$\mathrm{Ra}_{gas}$
Used in
$h_{conv_{og}}$