Study of Droplet Hydrodynamics in Oxygen Steel Making Process using VOF Method

Description

This book gives information for development of model to understand the oxygen blown mechanism in basic oxygen steel making process. In the beginning, an attempt is made to study some fundamental aspects of rising bubbles (liquid-gas) in stagnant Newtonian fluid using a Volume of Fluid (VOF) method. After successful validation of this model is applied for liquid-liquid system (molten metal-slag). For low value of Eotvos number/Reynolds number (Eo ≈ 1/Re≈ 1) terminal shape of rising bubble remains constant. Asthe bubble size increases or in between intermediate value of Eotvos number/Reynolds number (1 <Eo<100/1 < Re < 100), the shape of bubble is significantly affected because of fluid properties. In this range various bubble shape such as ellipsoidal, skirt and spherical cap bubble shapes areformed. For higher value of these dimension less number (100 <Eo< 200 / 100 < Re < 200) bubble shape turn out to be more toroidal. When the value of Eotvos number/Reynolds numberlie in between (30 <Eo/Re < 100) bubble shape turns in to spherical cap bubble shape and for100<Eo<200 bubble changes into oblate ellipsoid bubble. For higher value of Eotvos number/Reynolds number (Eo/Re>500) wake formation will be more and bubble leads towards the instability.
In addition, rising velocity of bubble also calculated for three different size (3, 4 and 5mm) of bubble and compared with the results which is obtained from available correlations.
The present work of air bubble/dropletrise behavior was well agreement with available literature results.
After that same model was applied for the basic oxygen steelmaking (BOF) process, and effect of ejection angle, diameter studied for generated droplet motion in basic oxygen steelmaking process, and also studied behavior of droplet in different type of slag. The continuity, momentum, and volume of fluid fraction equations were solved with the help of ANSYS-FLUENT(version 15), using finite volume method. The pressure implicit with splitting operators (PISO) algorithm was applied to solve the pressure-velocity coupling.
Therefore, reading the book can help one to get deeper and give thorough understanding inthe field of basic oxygen steel making process.