Issue 37

E. Mihailov et alii, Frattura ed Integrità Strutturale, 37 (2016) 297-304; DOI: 10.3221/IGF-ESIS.37.39 298 From the published models[1-3] for the analysis of heat transfer process in the work area of the electric arc steelmaking furnaces(EASF) using the water cooling elements two ways are used: 1. Outer heat transfer at stationary heat conduction of the wall, roof and metal at which the electric arc can be taken as a point energy source. 2. Outer and inner heat transfer on the basis of immediately heat balance of the whole system. The heat balance of the working area of EASF can be given with the equation [2]: el w g el c m a QQQ QQP      . , (1) In the heat exchange description, the chamber space of the secondary steelmaking electric arc furnaces (Fig. 1) was reduced to two surfaces (F sum =F m +F w-f and F c.el ) forming a closed space. h D Ar F m F w-f F c.el F sum F c l .el Figure 1: Ladle furnace scheme and heat transfer areas. Scheme of the heat balance and different heat flows in water-cooled element is presented on Fig. 2. w w el c el c ins ins r elc r T Q T               1 . . . F m  v out w T in w T   in w out w ww elc T T C Q m    .   in w out w w w el c T T mC Q    . el c .  p D el c .  ins            el c el c ins ins r el c r wc r QT T . . .     w el c el c ins ins w r r el c T T Q      1 . . .     ins ins r el c r c ins r QT T   .    elc .  ins  ins ins     2 out w in w w T T T   l el c Q .   l el c el c refl Q Q . . 1   el c own abs r el c Q Q Q Q . .    4 . . . . 100 . .         r el c l el c el c el c T Q Q      4 . 100 . r elc own T Q    0,14 s w 0,33 0,8 p w w Pr 0,027Re D            pipe of cooled elements insulation     Figure 2 : Scheme of the heat balance and different heat flows in water-cooled.