This paper presents a state-of-the art review on utilization of artificial intelligence in functional modification of multiphase fluids. The basic concept of such intelligent functional multiphase mixtures has been proposed and several related background technologies have been presented for R & D. Some historical backgrounds behind this topic was also documented.

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The first-order upwind difference method is usually used for the two-phase flow analysis in order to maintain numerical stability whereas the high-order upwind difference method is seldom used. It is, however, difficult to obtain a highly accurate numerical solution using the first-order method because it has large numerical diffusion when the distributions of velocity and void fraction are discontinuous. In the previous reports, the numerical stability of the high-order upwind difference method was clarified using a linear model equation of the two-fluid model and the actual two-fluid model. In this report, we calculated the problem having discontinuous velocity and void fraction distributions with the two-fluid model and examined the accuracy of the numerical solution when the high-order upwind difference method was used. It was shown that the high-order upwind difference method gives a more accurate numerical solution than the first-order method. It was also shown that the maximum time step that can be used for stable calculation hardly increases by using the high-order method. The computational efficiency is, hence, almost the same between the high-order method and the first-order method.

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Vibration syndrome approved as an industrial disease in our country brings the disturbances of peripheral circulation (Raynaud's phenomenon), when the vibration is transmitted to human body from oscillating tools. The clarification of the mechanism of the crisis is an important subject in the field of bioengineering. It is thought that the bubble generation in blood with an oscillation relates to thecause of the vibration disease. In this work, the environment conditions about the bubble generation in liquids are studied experimentally.

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It's necessary to consider the interaction force between solid-and liquid-phase in two-phase flows. In this paper, the governing equations of solid-liquid flows are established by space average and Reynolds average mothers. The drag force of particles is evaluated on the basis of experiments of solid-liquid flow in vertical tube. The results show that the accumulation effect of particles on drag force is closely to the particles concentration and relative density of two-phase flow.

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[in Japanese]

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