Cableizer
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Coefficient K to calculate in air

Symbol
$K_A$
Formulae
$\frac{\pi D_o h_{bs}}{1+\lambda_1+\lambda_2+\lambda_3} T_{int}$cable
$\frac{\pi D_o h_{bs}}{1+\lambda_1} T_{int}$PAC/GIL
Related
$D_o$
Outer diameter [m]
$h_{bs}$
Heat dissipation coefficient for black surfaces in free air [W/m$^2$/K$^{5/4}$]
$\lambda_1$
Loss factor of shield (screen and sheath)
$\lambda_2$
Loss factor of armour
$\lambda_3$
Loss factor of steel pipes for pipe-type cables
$\pi$
Archimedes' constant $\pi$
$T_{int}$
Internal thermal resistance for current losses [K.m/W]
Used in
$\Delta \theta_s$
Temperature difference surface to ambient [K]