SUMMARY The capability of the direct volume of fluid method for describing the surface dynamics of a free two‐dimensional rising bubble is evaluated using quantities of a recently published benchmark. The model equations are implemented in the open source computational fluid dynamics library OpenFOAM®. Here, a main ingredient of the numerical method is the so‐called surface compression that corrects the fluxes near the interface between two phases. The application of this method with respect to two test cases of a benchmark is considered in the main part. The test cases differ in physical properties, thus in different surface tension effects. The quantities centre of mass position, circularity and rise velocity are tracked over time and compared with the ones given in the benchmark. For test case one, where surface tension effects are more pre‐eminent, deviations from the benchmark results become more obvious. However, the flow features are still within reasonable range. Nevertheless, for test case two, which has higher density and viscosity ratios and above all a lower influence of the surface tension force, good agreement compared with the benchmark reference results is achieved. This paper demonstrates the good capabilities of the direct volume of fluid method with surface compression with regard to the preservation of sharp interfaces, boundedness, mass conservation and low computational time. Some limitation regarding the occurrence of parasitic currents, bad pressure jump prediction and bad grid convergence have been observed. With these restrictions in mind, the method is suitable for the simulation of similar two‐phase flow configurations. Copyright © 2012 John Wiley & Sons, Ltd.

The temperature dependence of surface tension and density for Fe-Cr-Mo (AISI 4142), Fe-Cr-Ni (AISI 304), and Fe-Cr-Mn-Ni TRIP/TWIP high-manganese (16 wt% Cr, 7 wt% Mn, and 3-9 wt% Ni) liquid alloys are investigated using the conventional maximum bubble pressure (MBP) and sessile drop (SD) methods. In addition, the surface tension of liquid steel is measured using the oscillating droplet method on electromagnetically levitated (EML) liquid droplets at the German Aerospace Centre (DLR, Cologne). The data of thermophysical properties for Fe-Cr-Mn-Ni is of major importance for modeling of infiltration and gas atomization processes in the prototyping of a ''TRIP-Matrix-Composite.'' The surface tension of TRIP/TWIP steel increased with an increase in temperature in MBP as well as in SD measurement. The manganese evaporation with the conventional measurement methods is not significantly high within the experiments (D Mn \ 0.5 %). The temperature coefficient of surface tension (dr/dT) is positive for liquid steel samples, which can be explained by the concentration of surface active elements. A slight influence of nickel on the surface tension of Fe-Cr-Mn-Ni steel was experimentally observed where r is decreased with increasing nickel content. EML measurement of high-manganese steel, however, is limited to the undercooling state of the liquid steel. The manganese evaporation strongly increased in excess of the liquidus temperature in levitation measurements and a mass loss of droplet of 5 % was observed.

The infiltration of liquid TRIP steel into a porous zirconium dioxide foam ceramics is a possible production line for a new composite material. This composite is currently under investigation in a joint research project, which should explore the basic features and possible designs of the new material. The paper presents a pore‐scale model for the numerical simulation of the infiltration process. Such simulations should help to develop optimised production processes for the composite. The qualitative and quantitative performance of the model is evaluated by comparison of simulation results with data from corresponding water model experiments. Good agreement between the numerical and the experimental results is found.

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