Numerical simulation of fluid flow and alloy melting in RH process for electrical steels

Computational Fluid Dynamics Modeling of Argon–Steel (–Slag) Multiphase Flow in an Ruhrstahl–Heraeus Degasser: A Review of Past Numerical Studies

“…Some of them might have considered bubble expansion, but they were not explicitly mentioned in their articles. As shown in Figure 4, the calculated liquid circulation rate without bubble expansion was only 43–47% of the measured values, and similar results were reported by Kishan et al, [ 13,69 ] Chen et al, [ 39,63 ] and Peixoto et al [ 72 ] In addition, in the study by Wang et al, [ 15 ] the predicted liquid circulation rate without bubble expansion was 73.4% of the value estimated by the empirical formula of Kuwabara et al [ 83 ] In addition, Liu et al [ 46 ] compared the results with and without bubble expansion and found that bubble expansion had a strong influence on the liquid flow in an industrial RH degasser.…”

“…Peixoto et al [ 72 ] also reported that the predicted value was approximately 80% of the actual value, and they suggested that a better numerical result could be obtained if thermal expansion was simultaneously considered. However, in the study of Wang et al, [ 15 ] the predicted values were in excellent agreement with the values estimated by the empirical formula of Kuwabara et al [ 83 ] with a small error of 1.8–3.3%.…”

“…In the last 20–30 years, three main CFD models have been adopted to simulate the fluid flow in an RH degasser, including the homogeneous fluid model, volume of fluid–discrete phase model (VOF–DPM) coupled model, and Eulerian model. In addition, single DPM, [ 13–15 ] single VOF, [ 16 ] and algebraic slip mixture (ASM) [ 17–19 ] models have also been used by some authors, which will not be separately reviewed in Section 2.…”

“…[ 17–19,43,46,59,61,63,65,66,69,75,76,80 ] Compared with the Schiller–Naumann model, [ 107 ] the Morsi–Alexander model [ 108 ] is more complete because it expands the Reynolds number to a large range, and this model has also been used by many authors. [ 13,15,38,40–43,45,52,65 ] In addition, the Haider–Levenspiel, [ 109 ] Kuo–Wallis, [ 110 ] Ishii–Zuber, [ 111 ] Tomiyama, [ 112 ] and Liu et al [ 113 ] models, based on bubble deformation, were, respectively, selected to describe the gas–liquid flow in an RH degasser by Chen et al, [ 39 ] Wei et al, [ 56,57 ] Peixoto et al, [ 72 ] Rimbert et al, [ 14 ] and Dong et al [ 51 ] Among them, a shape factor was used to consider the bubble deformation by Chen et al [ 39 ] and Dong et al, [ 51 ] and the bubble shape was not addressed explicitly by Rimbert et al [ 14 ] and Peixoto et al [ 72 ] Recently, Ling et al [ 43 ] investigated the effect of several drag coefficient models on the gas–liquid two‐phase flow in the physical model of an RH degasser, and found that the Schiller–Naumann [ 107 ] and Morsi–Alexander [ 108 ] models, based on spherical bubbles, provided better prediction in terms of the liquid velocity. However, a puzzling result was obtained in the study by Cao et al, [ 52 ] in which the liquid could hardly circulate by using the Schiller–Naumann model, [ 107 ] but the liquid velocity could be well predicted by using the Morsi–Alexander model [ 108 ] for the simulation of the physical model of an RH degasser.…”

“…model (VOF-DPM) coupled model, and Eulerian model. In addition, single DPM, [13][14][15] single VOF, [16] and algebraic slip mixture (ASM) [17][18][19] models have also been used by some authors, which will not be separately reviewed in Section 2.…”