Radiation thermal resistance between cable surface and inner wall of the tunnel.

Symbol
$T_{\mathrm{st}}$
Unit
K.m/W
Formulae
$\frac{1}{D_{\mathrm{o}} K_{\mathrm{r}} K_{\mathrm{t}} \pi \sigma \left(\left(\theta_{\mathrm{de}} + 273\right)^{2} + \left(\theta_{\mathrm{t}} + 273\right)^{2}\right) \left(\theta_{\mathrm{de}} + \theta_{\mathrm{t}} + 546\right)}$Aegerter/Meier
$\frac{1}{D_{\mathrm{o}} K_{\mathrm{r}} K_{\mathrm{t}} \pi \sigma \left(\left(\theta_{\mathrm{o_{\mathrm{L}}}} + 273\right)^{2} + \left(\theta_{\mathrm{t_{\mathrm{L}}}} + 273\right)^{2}\right) \left(\theta_{\mathrm{o_{\mathrm{L}}}} + \theta_{\mathrm{t_{\mathrm{L}}}} + 546\right)}$IEC 60287-2-3
Related
$D_{\mathrm{o}}$
$K_{\mathrm{r}}$
$K_{\mathrm{t}}$
$\sigma$
$\theta_{\mathrm{de}}$
$\theta_{\mathrm{o_{\mathrm{L}}}}$
$\theta_{\mathrm{t}}$
$\theta_{\mathrm{t_{\mathrm{L}}}}$
Used in
$T_{\mathrm{a}}$
$T_{\mathrm{s}}$
$T_{\mathrm{t}}$
$\theta_{\mathrm{de}}$
$\theta_{\mathrm{hs}}$
$W_{\mathrm{hs}}$