Rayleigh number gas/duct

Symbol
$\mathrm{Ra}_{gas}$
Formulae
$\mathrm{Gr}_{og} \mathrm{Pr}_{gas}$object to gas
$\mathrm{Gr}_{gd} \mathrm{Pr}_{gas}$gas to duct
$\mathrm{Gr}_{da} \mathrm{Pr}_{gas}$duct to ambient
$\mathrm{Gr}_{od} \mathrm{Pr}_{gas}$object to duct
Related
$\mathrm{Gr}_{da}$
$\mathrm{Gr}_{gd}$
$\mathrm{Pr}_{gas}$
Used in
$\mathrm{Nu}_{og}$