Fluid buckling or liquid rope coiling, which is one of low-Reynolds number instabilities, is simulated using the two-phase lattice Boltzmann method with large density differences. In the present calculations, a highly viscous liquid jet in a gas phase falls vertically against a flat plate under gravitational force. We investigate the effect of the Reynolds number (Re) and the Froude number (Fr) on buckling instability. Also, the calculated results of jet behavior are compared with those by experiments of the authors' own carrying out. According to the present simulations, for Re=32 and Fr=2.9 the jet falls down stably without oscillation. On the other hand, for Re=0.40 and Fr=0.37 in which the instability condition of the Reynolds number is satisfied, the fluid buckling occurs and the jet behavior is in qualitative agreement with experimental results.

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Based on the CIP/Multi-Moment concept, a simple finite volume method, namely VSIAM3 (Volume/Surface Integrated Average based Multi-Moment Method) has been constructed and implemented to multi-fluid simulations. Using both VIA and SIA as the model variables, VSIAM3 has compact stencil and shows remarkable flexibility and robustness in a wide spectrum of simulations for complex fluids, thus is well-suited for inter facial multi-fluid flows. An simple algebraic scheme for capturing moving interface using hyperbolic tangent function, THING (Tangent of Hyperbola for Interface Capturing), is devised and incorporated to the VSIAM3 model. THING scheme exactly conserves the transported fluid fraction and, without the geometrical reconstruction as those required in the conventional VOF method, is very simple and easy to use.

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The soroban grid system that can capture the gas-liquid interface sharply is proposed. This grid system consists of the straight lines and grid points on these lines. Combination the flexible soroban mesh and the CIP (cubic interpolated propagation) method produces interface capturing and high order accuracy. Algorithm of mesh generation is very simple and the soroban mesh can be generated at short times.

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Numerical Analyses of Glass Tank Furnace are performed which include direct Joule heating by electricity. Effects of tank refractory and glass on heating distribution, temperature distribution and flow distribution, is investigated. The results indicate that for the case of glass with low electric resistance ZFC refractory, which has superior performance for high temperature corrosion and for glass defects, is suitable. Whereas, the results show the problem of local heating at refractory when ZFC refractory is used for glass with high electric resistance. In case of using ZFCR which has high electric resistance with not less than the same performance as ZFC, the suitable result is found even for the glass with high electric resistance. The Fluid/Temperature/Electricity combined computational analysis makes it possible to select appropriate refractory for various kind of glass composition to be manufactured.

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Hydrogen is expected as new fuel instead of fossil fuel. Many scientists are studying characteristic features of hydrogen. But it is difficult to experiment the hydrogen dispersion in case of hydrogen leaks, because hydrogen has the properties that energy for ignition is lower and flammable range of mixture gas is larger than those of hydrocarbon fuel. Therefore clarifying the hydrogen dispersion with numerical analysis becomes important. This paper describes a finite element method for solving Navier-Stokes equations and the advection-diffusion equation. Numerical results are also shown for a simple model.

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Large-eddy Simulation of compressible transitional flows in a low-pressure turbine cascade is performed by using 6^<th>-order compact difference and 10^<th>-order filtering method. Numerical results without free-stream turbulence and those with about 5% of free-stream turbulence are compared. In these simulations, high-accuracy Large-eddy Simulation which resolves growth of boundary layer and its fluctuation in compressible transitional turbine cascade flows is realized. Based on these results, Snapshot POD (Proper Orthogonal Decomposition) Analysis is also performed in order to investigate dominant behaviors of the unsteady boundary layers.

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The misfit dislocation at the γ/γ' interface of Ni-based superalloys were investigated using the quasicontinuum simulation. In order to mimic the γ/γ' interface, the lattice parameter of Ni is slightly changed by modifying the embedding function. The positive/negative misfit is set on the γ' phases, developing the formation of misfit dislocations at the γ/γ' interface. In the simulation of a flat γ/γ' interface, it is found that the dislocations have edge characters and the interval spacing is depend on the magnitude of the lattice misfit. Then the effects of edge's shape were also investigated between round and square edge.

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