Cableizer ®

Air temperature increase

Fictitious increase of ambient temperature to account for the ventilation in a tunnel.

Symbol
$\Delta \theta_{0t}$
Unit
K
Formulas
$\frac{\left(\theta_{init}-\theta_{a}\right) \left(T_{t}+T_{e}\right)}{T_{a}+T_{t}+T_{e}} e^{\frac{-L_{T}}{L_{0}}}$
Related
$L_{0}$
Reference length of the tunnel [m]
$L_{T}$
Length tunnel [m]
$T_{a}$
Star thermal resistance air [K.m/W]
$T_{e}$
External thermal resistance of tunnel [K.m/W]
$T_{t}$
Star thermal resistance tunnel [K.m/W]
$\theta_{a}$
Ambient temperature [°C]
$\theta_{init}$
Air temperature without load [°C]
Used in
$I_{c}$
Conductor current [A]
$\theta_{c}$
Temperature conductor [°C]