Temperature of duct outer wall

Symbol
$\theta_{de}$
Unit
$^{\circ}$C
Formulae
$\frac{T_{4ii} W_{p} n_{cc}}{2} - T_{4ii} W_{t} n_{cc} + \theta_{di}$cable(s) in duct
$\frac{T_{sa} T_{st} W_{tot} + T_{sa} \theta_{t} + T_{st} \theta_{at}}{T_{sa} + T_{st}}$cable/heat source in tunnel
$- T_{4ii} W_{t} n_{cc} + \theta_{di}$cable in trough or channel
$- T_{4ii} W_{hs} + \theta_{di}$heat source in duct
$\theta_{at}$
$\theta_{di}$
$\theta_{t}$
$W_{p}$
Used in
$\alpha_{st}$
$\theta_{c}$