Particle method is a meshless method mainly developed for fluid analysis. Feature of this method is that continuum is represented by a finite number of particles and dynamics is calculated by movement of particles. In this paper a three-dimensional particle method for elastic shells is developed using an explicit spring model. In this method virtual particles placed in the normal direction connected with neighbor particles by springs, and the particles move by the spring force. The spring constant is determined by the bending rigidity of the plate. The lateral vibration is analyzed by this method and results are compared with the classical plate theory.

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This paper describes the 2D crack propagation analysis using the Free Mesh Method (FMM). The computational fracture mechanics involves frequent re-meshing as the crack propagating. In order to show the effectiveness of the FMM in crack propagation analysis, we solve the 2D crack propagation problems with the FMM. The method controlling the crack propagation will be proposed using Neural Network.

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Free Mesh Method which is a kind of meshless method is the technique that is particularly effective for crack propagation analysis. It is applied to the two-dimensional crack problem so far. However, it is difficult to use quadratic elements in Free Mesh Method. Therefore the accuracy of the stress field of the crack tip is assumed to be insufficient. This study proposes the introduction of Enriched Free Mesh Method to make highly accurate crack propagation analysis.

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A new method is developed to visualize simulation results which include the fracture of elastic material. Moving Particle Semi-implicit Method (MPS) is used to simulate the behavior of elastic material. Separation tensor is introduced, which describes the state of balancing force at each particle. The separation tensor is used to predict the occurrence and the direction of fracture. For the visualization of the simulation results, the vertices of polygons are related to the position of the nearest particle and they are moved according to the displacement of the particle. When the fracture occurs, they are visualized by generating new polygons around the fracture.

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The smoothed particle hydrodynamics (SPH) method is applied to the numerical simulation of cutting of a solid body by a high-speed water jet. Water is modeled as a viscous fluid with weak compressibility. A solid body is modeled as an elastic material. The water and solid body are discretized into a lot of particles. These particles are moved in a Lagrangian manner according to the governing equations of motion of water and solid body. Numerical calculations are carried out in 2-dimension and 3-dimension for a solid like wood. Encouraging numerical results have been obtained.

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The influence of the carburizing on the gear shape after the quenching was investigated by heat-treatment simulation. In the heat-treatment simulation of the carburized gear, considering the effect of the carbon content on the material properties, i.e., the stress-strain curves and martensite transformation temperature, the analysis accuracy was significantly improved. It is found that the carbon content dependencies of material properties should be considered in the simulation to predict the deformation of the gear accurately.

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Phase field simulation has become one of the most effective methods to predict the microstructure in solidified materials including complicated dendritic pattern. The author and his colleagues have derived a set off coupling equations among phase, temperature and stress/strain by using a phase field model, and demonstrated several simulations on stress evolution and residual stress distribution in solidification structures. The fundamental equations and simulation results in a solidified material with complicated dendritic structure are represented in this report, and the advantage of this model for evaluating stress distribution and remained problems to be improved are discussed by referring those equations and results.

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CFD difference scheme for structured grid system is derived. This Technique is able to apply for object with complex shape, and to generate analysis model automatically and quickly from CAD data. Furthermore, this technique enable to solve the flow around thin plate structures, and various moving boundary problems.

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Tsunami is the severe problem occurs in neighbering waters arround Japan. But previous numerical approach is limited withen wide area analysis, detailed analysis using CFD is very rare. We have solved Tsunami as flow with free sutface numerically by VOF technique, and evaluate surface pressure loading real building with and without windows.

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Direct Numerical Simulation (DNS) Technique is developed for prediction of wind pressure on building structure with edge. This Technique has got good agreement to the results for the cube and the roof structure in comparison with Wind Experiments.

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CFD Technique for moving boundary is described. Super Cartesian method for expressing 3-dimensional complex shape enables to move boundary suefaces defined form CAD data. Analysis examples of mobing auto mobile are explained.

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In micro systems such as micro-electro mechanical systems (MEMS), gap flow between systems and the surrounding wall changes due to the vibration of systems, and it may cause intense and complex interaction between the motion of systems and fluid flow. This research deals with vortex-induced transverse vibration of a spring-supported circular cylinder in a narrow channel. The objective is to clarify the effect of channel wall on the lock-in phenomena numerically, with the two-dimensional model. The marker-and-cell (MAC) method is applied in the numerical calculation. It was found that the lock-in region becomes narrow when the gap between the wall and the cylinder becomes small.

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Moving boundary CFD technique based on Cartesian grid was applied to air flow arround vehicle Bodys. This technique can simulate the behaviers of velocity and pressure distribution arround moving vehicles in the carm air and wind. The prediction results for carve running and running in crosswind are discussed.

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Numerical analysis technique with high speed and high accuracy for radiation problem is developed. This technique is called Top Priority method offers the efficient selection of relations between descritized surfaces as to computation of Stefan Boltzmann Equation. Several examples are discussed for showing this techinique.

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This paper deals with the numerical analysis of the interaction among gas, liquid and solid phases by the combined use of the fictitious domain and the level set methods. Fluid-solid interaction is treated by the fictitious domain method. Gaseous and liquid phases are treated by the level set method. As a numerical example, the flow of gas and liquid around a circular rigid body penetrating into a still liquid has been calculated. Encouraging results have been obtained.

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