Characteristics of singular field around interface edge between elastic and elastic-plastic joint were investigated theoretically. Finite element simulations have been conducted to acomplish the quantitative examinations with the theoretical results. Elastic/linear hardening material interface edge prediction and elastic/power law hardening material interface edge prediction were considered in the analysis. The simulation results of stress distribution clearly shows that the singular fields exist around the interface edge between the elastic and elastic-plastic joint beam. A seperable form function of stress distribution are examined around the interface edge.

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When a heavy cargo undergoes a moving process by a jib crane, the cargo begins swinging motion, due to its acceleration and deceleration. If the swing suppression capability is integrated in the crane operation system, its transportation efficiency would not be disturbed. When a cargo undergoes a circular motion, the swing motion must be divided into a circumferential component and radial component. But because the initial swing motion would keep its direction, boom raising and boom rotating must be controlled simultaneously. In this paper, the simultaneous control technique of the crane rotation and cargo swinging is proposed.

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It is well known that the Busemann biplane can completely cancel the shock waves propagating to the farfield, in two dimensional linear theory with no lift. A new concept of a boomless supersonic transport, which aims for a complete cancellation of the sonic boom of a supersonic transport by applying this theory, is proposed. As a first step, thee performance of Busemann biplane is evaluated, beyond 2D(two dimensional) linear theory. Effects of the nonlinear terms are investigated using 2D Euler simulations. Optimization is carried out to investigate how close the nonlinear analysis results compare to results from linear analysis.

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A combined experimental and numerical study has been carried out in order to study the mechanism of initial failure in transversely loaded CF/epoxy composites. The failure initiation under transverse tensile loading was investigated in a scanning electron microscope (SEM). It was observed that interfacial failure was the dominating failure mechanism for both materials. The applied load that caused initial failure in the experiment was applied as a global load in a microscopic finite element (FE) calculation. The numerical calculation could explain the experimentally observed results. Furthermore an upper limit of the interfacial normal (INS) and shear (ISS) strength was determined.

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Design of strength for plastic molding of polyoxymethylene(POM) has been examined by the nonlinear finite element method with the development of voids. It was assumed that the failure of fibrils on the craze causes the brittle fracture and the ductile fracture is due to the critical strain. The analytical result for the three point bending test with U notch bars was in agreement with the experimental values.

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In the present paper, we describe numerical simulation of process which produces nanoparticles by hydrothermal synthesis in supercritical phase, where the reactants and the hot water are mixed in the reactor and consequently nanoparticles precipitate through chemical reaction, nucleation and crystal growth processes. The mathematical model of the process shown here links the kinetics of chemical reaction, nucreation and crystal growth to the thermo-fluid dynamics in a wide range of temperature below and above the critical point, at which the themophysical properties such as density change very significantly.

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A numerical method for solving not only gas but also liquid and solid in critical conditions such as supercritical high pressure and high temperature conditions is proposed. This method is based on the preconditioning method and the real gas equation of state(EOS). The Peng-Robinson EOS is employed to approximate the supercritical fluids. Thermal properties of the supercritical fluids are evaluated by theoretical and experimental approaches. Since this method allows zero velocity fields without the stiffness, the thermal conduction in solid states are also solvable using the present method. As a typical numerical example, a micro-scale near-critical carbon-dioxide flow around the NACA0012 airfoil with the solid skin in the airfoil is calculated and the calculated temperature contours around and in the airfoil are shown.

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In this study, transonic humid-air and wet-steam turbulent flows through a steam turbine cascade channel are calculated. Transonic condensate flows in turbomachinery are numerically predicted by using the high-resolution method developed by our group. Fundamental equations consist of conservation laws of mixed gas, water vapor, water liquid, and the number density of water droplets, coupled with the momentum equations and the energy equation. The classical condensation theory is employed for modeling homogeneous nucleation and non-equilibrium condensation. These equations are solved by a high-order high-resolution finite-difference method based on the fourth-order compact MUSCL TVD scheme, Roe's approximate Riemann solver, and the LU-SGS scheme. SST model is used for evaluating eddy-viscosity.

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Unsteady transonic flows and unsteady flows at very low Mach number with condensation are numerically. Investigated by using the preconditioned Roe scheme and the preconditioned LU-SGS scheme based on the preconditioning method and the condensation model. The present method is certainly applicable to the unsteady transonic flows. On the other hand, the unsteady flows at very low Mach number calculated by the preconditioning method should be carefully validated because of the artificial compressibility in the preconditioning method. In this paper, unsteady flows at very low Mach number around a circular cylinder with and without condensation are calculated and the unsteady results are compared with the existing experimental data. Finally, the extensity of the present method to the unsteady flow problems is discussed.

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Molecular dynamics analysis is executed in order to investigate the atomistic mechanism of the shape memory effect. As an interatomic potential, the embedded-atom-method potential for NJ-Al alloy is applied. A series of thermo-mechanical loading is applied to the MD. Model, and the shape memory effect, consisting of deformation by shear loding, only elastic recovery by unloading, the inverse transformation from martensite to bcc by heating, and martensitic transformation. By cooling, is successfully observed. The dependency of the model size and the initial configuration on the result is also discussed so as to explain the difference of the atomistic stress-strain curve and the macroscopic one.

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A statistical mechanics of long chain molecules has been used as an alternative to the continuum mechanics approach to develop constitutive model of the soft tissue. By this method, molecules are assembled and represented in a unit cell that is the basic element of network model. Regarding to the latest developed network model which is called eight-chain model, a unit cell consists of eight chains. Each long-chain is composed of a number of rigid links, and represents a collagen fiber. In nonlinear modeling, the Langevin function is employed as a statistical function to determine the length of chainss after deformation. There are five parameters, that is, the density of the constituent molecule chains, the bulk modulus, and the height, width, and depth of the unit cell, necessary to characterize mechanical property of material. However, wever, the relationships of parameters to constitutive equation are not fully understood. The purpose of this study is to investigate and understand the significance of these five material parameters to the constitutive law, based on simulation results.

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