Cableizer

Rayleigh number gas→riser/tray

Symbol
$\mathrm{Ra}_{int}$
Formulas
$\mathrm{Gr}_{og} \mathrm{Pr}_{gas}$riser: object→gas
$\mathrm{Gr}_{gd} \mathrm{Pr}_{gas}$riser: gas→duct
$\mathrm{Gr}_{int} \mathrm{Pr}_{gas}$riser: object→duct
$\frac{g \mathrm{Pr}_{gas} \beta_{gas} \left(\theta_{e}-\theta_{di}\right) {\delta_{d}}^3}{{\nu_{gas}}^2}$riser: object→duct, Chippendale, IEC 60287
$\frac{g \mathrm{Pr}_{gas} \beta_{gas} \left(\theta_{e}-\theta_{t}\right) {w_{t}}^3}{{\nu_{gas}}^2}$tray: object→tray top
Related
$\beta_{gas}$
Volumetric thermal expansion coefficient gas [1/K]
$\delta_{d}$
Distance cable—duct [m]
$g$
Standard acceleration of gravity [m/s$^2$]
$\mathrm{Gr}_{gd}$
Grashof number gas—duct
$\mathrm{Gr}_{og}$
Grashof number cable—gas
$\nu_{gas}$
Kinematic viscosity gas [m$^2$/s]
$\mathrm{Pr}_{gas}$
Prandtl number gas
$\theta_{di}$
Temperature duct inner surface [°C]
$\theta_{e}$
External temperature object [°C]
$\theta_{t}$
Temperature wall (inner) [°C]
$w_{t}$
Width (inner) [m]
Used in
$h_{conv,int}$
Heat transfer coefficient convection cable—riser/tray [W/(K.m$^2$)]
$\mathrm{Nu}_{int}$
Nusselt number cable—riser/tray
$\mathrm{Nu}_{og}$
Nusselt number cable—gas