The phenomenon of solid inclusion nucleation and V m molar volume, m3 molÕ 1 growth during the liquid steel deoxidation process is studied numerically. It is shown that the diffusion a i number of pseudomolecules which dissociate of atoms, the Ostwald ripening effect, and per unit time from unit area of particle of class Brownian movement together control the growth of i, mÕ 2 sÕ 1 small size particles. It appears that this stage of b 1i rate constant of growth reaction initial precipitation lasts for only about 10 s. When (i)+ (1) ! (i+ 1), m3 sÕ 1 the particle diameter exceeds a threshold of d i,j collision rate constant, m3 sÕ 1 ~1 mm, the growth process becomes dominated by e turbulent energy dissipation rate, m2 sÕ 3 particle collisions and agglomeration. The efficiency m dynamic viscosity of liquid, Pa s of these mechanisms depends on the particle size n kinematic viscosity of liquid, m2 sÕ 1 distribution as produced during growth. P supersaturation of parent phase or Comprehensive evaluations are still impeded by the dimensionless concentration of limited capacity of computers at present. I&S/1774 pseudomolecules r L density of liquid, kg mÕ 3 At the time the work was carried out the authors were r p density of particles, kg mÕ 3

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In order to study slag carryover during ladle teeming, the last stage of ladle draining is simulated by means of a 1:1 scale water model with reduced wall height. The flow phenomenon “drain sink” is found to be responsible for slag carryover. A drain sink occurs if the volume flow of the open channel at the ladle bottom becomes less than the corresponding outlet capacity. This explanation is confirmed quantitatively by experimental data and a simple hydraulic model as well as by steelmaking experiments. At present, a gravimetric method of slag flow detection is being tested in the continuous casting plant.

According to current practice, the desulphurisation of steel melts is mainly performed in the ladle with lime saturated top slags. The injection of argon gas into liquid steel provides for intensive mixing and accelerated sulphur transfer. During gas stirring treatment, an emulsification of top slag takes place. A numerical model describing the course of the desulphurisation reaction has been developed, which takes all relevant process parameters into account, including those of the emulsification effect. To check the validity of the model, operational tests have been performed on 185‐t‐heats. Results obtained from model calculations and operational tests show an excellent agreement.

The control of the liquid metal flow and the damping of surface fluctuations are predominant objects connected with the operation of wide mould casters. Investigations on a full scale water model reveal that the casting speed, the immersion depth of the entry nozzle, and the lift gas injection rate have to be tuned carefully for the benefit of optimal flow conditions in the CC‐mould. When casting conditions are changed, it is necessary to adjust the free parameters correspondingly in order to maintain smooth casting operation and high ranking strand quality.