RT Journal Article SR Electronic A1 Kavicka, Frantisek A1 Stetina, Josef A1 Sekanina, Bohumil A1 Masarik, Milos T1 Definition of Boundary Conditions for the Numerical Model of Transient Temperaturefield of a Concast Steel Slab JF Communications - Scientific Letters of the University of Zilina YR 2012 VO 14 IS 11 SP 13 OP 17 DO 10.26552/com.C.2012.4A.13-17 UL https://komunikacie.uniza.sk/artkey/csl-201211-0002.php AB The solidification and cooling of a continuously cast billet, slab or cylinder (generally a concasting) is a very complicated problem of 3-D transient heat and mass transfer. This paper is focused on the derivation of boundary conditions, i.e. the values of the heat transfer coefficient (HTC) on all boundaries of the concasting machine (CCM). The definition of boundary conditions is the most difficult part of the investigation of the thermokinetics of this process. The boundary conditions in the numerical model of the temperature field of the concasting are defined as the heat transfer by convection. This HTC includes the so-called reduced convection coefficient corresponding to heat transfer by radiation. This paper therefore continues with a discussion on heat transfer coefficients under air-water cooling jets, which spray the concasting in the so-called secondary-cooling zone.