I am designing a Helmholtz Coil with radius 0.5m with 20 gauge Copper wire having 1000 turns. The power generated by passing 1A current through the coil is around 130W. One coil weighs 15.4kg and the cylindrical surface area exposed to air is 0.364m^2. I need to calculate the steady state temperature of the coil to see whether the coil would get too hot to operate safely. I am assuming that the coil cools down via conduction through air since the coil would be indoors. What would be the best way to get a rough estimate of the temperature at the surface of the coil?