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In single-phase flow visualization, research focuses on the analysis of vector field properties. In two-phase flow, in contrast, analysis of the phase components is typically of major interest. So far, visualization research of two-phase flow concentrated on proper interface reconstruction and the analysis thereof. In this paper, we present a novel visualization technique that enables the investigation of complex two-phase flow phenomena with respect to the physics of breakup and coalescence of inclusions. On the one hand, we adapt dimensionless quantities for a localized analysis of phase instability and breakup, and provide detailed inspection of breakup dynamics with emphasis on oscillation and its interplay with rotational motion. On the other hand, we present a parametric tightly linked space-time visualization approach for an effective interactive representation of the overall dynamics. We demonstrate the utility of our approach using several two-phase CFD datasets.

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Direct Numerical Simulations of the primary breakup of an inelastic non-Newtonian liquid jet with inflow turbulence are presented in this paper. The jet's structure, surface behavior, non-Newtonian characteristics as well as its specific breakup mechanism are investigated and discussed. The shear thinning viscosity of the liquid phase plays an important role during jet injection resulting in circumferential rotation of interfacial waves. Streamwise contra-rotating vortex pairs as well as triple vortex structures are observed in the liquid phase. The local Ohnesorge number, which has a branch-structure distribution in the liquid phase before disintegration, is found to be 30% smaller in regions near the nozzle exit and in the shear layer than in the jet tip, suggesting a clear non-Newtonian influence. A cavity breakup mechanism for this type of non-Newtonian jet is identified and explained, giving a new perspective for jet disintegration analysis.

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