Definice okrajových podmínek pro numerický model nestacionárního teplotního pole kontinuálně odlévané bramy

Definition of boundary conditions for the numerical model of transient temperature field of a concast steel slab

journal article - other

en

The solidification and cooling of a continuously cast billet, slab or cylinder (generally a concasting) is a very complicated problem of 3D 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.

Tuhnutí a chladnutí kontinuálně odlévaných sochorů, bram nebo válců je komplikovaný problem 3D nestacionárního přenosu tepla a hmoty. Příspěvek je zaměřen na odvození okrajových podmínek, t.j. hodnot součinitelů přestupu tepla ve všech částech licího stroje. Okrajové podmínky v použitém numerickém modelu jsou definovány jako přenos tepla konvekcí, kde je zahrnut i součinitel vyjadřující vliv radiace. Je diskutován přenos tepla při ostřiku vodo vzdušnými tryskami v sekundární chladicí zoně.

The solidification and cooling of a continuously cast billet, slab or cylinder (generally a concasting) is a very complicated problem of 3D 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.

Kontinuálně odlévaná brama, okrajové podmínky, chladicí charakteristiky

Concast slab, boundary conditions, cooling characteristics

2012

10.12.2012

Žilinská univerzita

Žilina

1335-4205

4A2012

14

13–17

5