Coefficient for convection to air, which is an experimentally determinded constant for heat transfer by convection from the cable surface to the air. The values in the standard for vertical and horizontal spacing are equal and thus not repeated here.
The standard does not give values for 2 cables. It was assumed that the values are identical to 3 cables.
|2||0.115||3 cables spaced (spacing >2 x D)||equal for horizontal and vertical spacing|
|3||0.086||3 cables touching (spacing <=2 x D)||equal for horizontal and vertical spacing|
|4||0.070||3 cables touching trefoil|