Cooling water volume is determined mainly by the electrical output. As a rule of thumb, approx. 27% of the furnace output is dissipated into the cooling water as heat loss from the coil and crucible wall, excluding converter losses.[1]
In the case of a 5-t furnace with 250 Hz and 3,000 kW, this gives 810 kW or
696,600 kcal/h, that must be dissipated at a temperature difference of 27 K. This
gives a cooling water volume of 25.8 m3/h (25,800 l/h). (kcal/h divided by the
temperature difference gives the volume in litres/h).
References
- Herbert H. Netzel: Induktionsofenhandbuch. 3rd edition, Eigenverlag IES, Witten 2003, p. 118. Empirical value, no manufacturer figure. On the same page the handbook also gives a rough estimate of 35% without stating its scope, and in the section on heat recovery (p. 222) states 900 kW for the same example furnace. We use the only figure with a stated scope (coil and crucible wall) and standardise on it.