Convection heat transfer coefficient, duct to air

Symbol
$h_{conv_{da}}$
Unit
W/(K.m$^2$)
Formulae
$\frac{\mathrm{Nu}_{da} k_{gas}}{L_{d}}$natural convection (no wind)
$\frac{2 \mathrm{Nu}_{da} k_{gas}}{D_{do}}$forced convection due to wind (>0.5 m/s)
$\left(h_{laminar}^{2} + h_{turbulent}^{2}\right)^{0.5}$natural and forced convection at low wind speed (≤0.5 m/s)
Related
$D_{do}$
$k_{gas}$
$\mathrm{Nu}_{da}$
Used in
$W_{conv_{da}}$