We study a surface model with a self-avoiding interaction by using the canonical Monte Carlo simulation technique on fixed-connectivity triangulated and spherical lattices. The model is a meshwork model, which is defined by a one-dimensional bending energy, the area energy, and the self-avoiding potential. The pressure term is also included in the Hamiltonian; the volume enclosed by the surface is well defined because of the self-avoidance. The meshwork model is known to have a rich variety of phases; the smooth spherical phase, the planar phase, the linear phase, and the collapsed phase, in the case without the self-avoiding interaction. The numerical results show that the planar phase appears only when the pressure is positive outside the surface in the self-avoiding model. Thus, we find that a role of self-avoiding interaction is to make the pressure positive inside the surface.

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The finite element method program becomes multifunctional as the computational mechanics technique develops, and it will be necessary to add more functions according to the progress of the research in the future. Naturally, it is not possible to correspond to the function addition of the kind of not assumed at first, though the possibility of the function addition is necessary to consider in any program. The use of the design patterns is advanced to correspond to more complex programming, though object-oriented programming approach is paid attention for more flexible programming. Here, the outline and directions of the Option pattern designed for the FEM program enhancing are demonstrated. Then execution performance is compared without the option design pattern.

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Recently probabilistic approaches in safety assessment have become more significant. Probabilistic fracture mechanics (PFM) has been applied to many fields such as nuclear power plants and airplanes. However most of PFM software were developed for specific problems, respectively. It takes much time and cost to modify an existing software for another field, or even more to develop a fully new software. To solve this problem, a new design of general purpose PFM software is proposed here by using object-oriented approach.

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Recently, the parallel processing using GPU(Graphics Processing Unit) get scientists and engineers attention. In this study, we made the CFD code based on the staggered grid and the HSMAC algorithm parallel by using GPGPU and aimed at speed-up. We checked the effectiveness on the NVIDIA Tesla C1060.

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In this paper, we estimated the applicability of an anisotropic hyperelastic model to the fabric of a competition swimwear. The fabric of a competition swimwear consists of chemical fiber. The fabric shows anisotropy that depends on fiber orientation angle. We used the model as the anisotropic hyperelastic model which was able to adjust each axial stiffness and share stiffness. The material parameters of the anisotropic hyperelastic model for the finite element method (FEM) analysis were determined by uniaxial tension test of the fabric. In order to show the applicability of the anisotropic model, we carried out FEM analysis. As a result, we clarified the mechanical characteristic of the fabric of the competition swimwear. The material consisting of a textile has orthotropy. In addition, we showed that the mechanical characteristic of the fabric of the competition swimwear could be reproduced by the anisotropic hyperelastic model.

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The purpose of this study is establishment of design methods for competitive swimwear using numerical analysis. The anisotoropic hyperelastic model is introduced into swimwear materials and the applicability of the model to swimwear is estimated. The swimwear is made of the fabric material. The materials have two mechanical properties. The one is nonlinear elasticity which is regarded as hyperelasticity like rubber. Another is anisotropic that depend on the directions of two fiber families. The properties of swimwear fabrics were estimated by uniaxial tensile tests, and anisotropic hyperelastic model is applied to the numerical modeling. The materials are plain weave and show anisotropic properties. So, Asai model which is possible to adjust stretch rigidity and shear rigidity separately is applied to them. Then, we determine the material parameters of them and verified their accuracy.

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We propose a new crack detection system based on natural frequency changes. In the previous study, we have succeeded in developing crack detection system based on genetic algorithm (GA). However, it is difficult to identity a crack in real time. In the present study, we employ the response surface method using the optimization tool Solver installed in Excel, which is less time consuming than the GA. Monitoring the minimum error between the natural frequencies obtained using the regression function and the natural frequencies obtained from the experiment, we detect the crack position and the crack length. By using both the response surface method and Excel macro program, we can identify the crack in real time.

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An interference fit is sometimes used to fasten two mating parts, e.g., a shaft and a hole, employing friction between the two parts. Inserting the shaft into the hole under interference fit, we must pay attention to the stress concentration around the hole. For example, on the near edge of the hole, high stress concentration arises on the hole, causing the plastic deformation and a misalignment of the shaft. This misalignment can also lead to abrasion of the surface of the two mating parts. Therefore, it is important to avoid this stress concentration under the interference fit. In our study, we propose a method for reducing the stresses on the contact area of the hole by cutting a groove into the side face of the hole. This cutting can release the contact stress between the two mating parts. On the other hand, this may weaken the frictional force of the contact surface. There is a trade-off between the cutting and the strong frictional force. Introducing an evaluation function of these two parameters and using the three-dimensional contact FEM analysis, we determine an optimal shape of the groove. Through the FEM simulation results, we demonstrate the validity of our method.

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If a crack exists in a material, it may cause a serious accident. To prevent the accident, the early crack detection is crucially important. In our previous study, we have succeeded in detecting a crack in a plate using the change of natural frequencies. In present study, by using the Mahalanobis distance method, we propose a new method which identify simultaneously the position and the length of the crack. Mahalanobis distance method is a useful way of determining similarity of an unknown sample set to a known one. Through the identify results, we demonstrate the validity of our approach.

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This paper proposes a single-specimen technique for determining the J-R curve of metallic materials. The stable crack extension is evaluated by two methods, such as Electric Potential Difference Method and Finite Element Method, which are applied for determining the K_<IH> (the threshold value for the onset of hydrogen enhanced crack growth for 21/4Cr-Mo steel). There is in close agreement between them in determining the K_<IH>.

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The parameter values of the extended Tersoff interatomic potential function applicable to strength analysis taking the effects of evironment into account is improved. Properties of Si, O_2, H_2, H_2O, SiH_4, and SiO_2 (α-quartz, α-crystbalite, β-quartz, and β-crystbalite) are calculated by using this parameter values. It is found that the calculated values of the properties coincide well with the experimental values.

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The method of the caustics is well known as a technique to measure the stress intensity factor. In this method, numerical simulation of the caustic image is necessary to evaluate the stress intensity factor. Since the plane stress state has been assumed in previous studies, experimental result doesn't coincide with the theoretical one when the caustic image is delivered from the vicinity of the crack tip. In such case, the caustic image becomes smaller than the theory in which plane stress is assumed. Accordingly, we developed a new simulation system of the caustic image for 3D stress field coupled with 3D FEM analysis. Our system could provide the caustic image that met experiment even the caustic image delivered from vicinity of the crack tip. Furthermore, we could obtain the image better agreed with the experiment, when we consider the stress distribution through the thickness direction in detail.

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In this paper, static and dynamic collapse characteristics of an energy absorption element, which is made of an aluminum alloy, are estimated by quasi-static compressive tests and drop weight tests, and strain rates for compressive and bending deformation mode are derived from strain history of strain gauges. The first peak force in the force-length relationship of the dynamic test is different from that of the static test. Because a compressive deformation concentrates at an end of the specimen, and high strain rate occurs at the end of the specimen. The average force in the plateau region of the dynamic test is similar to that of the static test. Because bending deformation occurs in large area of the specimen, and the strain rate is sufficiently low.

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In this study, the analysis of stress distribution generated to die automobile hub by the cornering force caused when turning had done for discuss optimum structure. The experiment used the model of automobile hub made with epoxy resin, the assumption parts of the bearing and brake plate and increased load to die automobile hub by using the assumption parts of die bearing. The analysis method was die photoelasticity. It was became clear by die analysis that die stress concentration by die cornering force became remarkable at the fillet R neighborhood in die boss root, die bolt hole, and die contact department with die brake plate. It is thought that optimum automobile hub can be made by discussing structure of die three points when designing.

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In Japan Atomic Energy Agency (JAEA), a study on flow induced vibration in the primary cooling system of Japan Sodium cooled Fast Reactor (JSFR) consisting of large diameter pipe and pipe elbow with short curvature radius has been conducted. Flow-induced vibration in the elbow is an important issue in design study of JSFR, because it may affect to structural integrity of the pipe. In this study, applicability of the Unsteady Reynolds Averaged Navie-Stokes equations (U-RANS) approach with the Reynolds Stress Model (RSM) using a commercial CFD code to the flow through the short-elbow under high Reynolds number condition was examined for the 1/10 scaled water experiment simulating the hot-leg piping of the JSFR. As a result, the time-step dependency is observed in flow structure.

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In Japan Atomic Energy Agency (JAEA), a study on flow induced vibration in the primary cooling system of Japan Sodium cooled Fast Reactor (JSFR) consisting of large diameter pipe and pipe elbow with short curvature radius has been conducted. Flow-induced vibration in the elbow is an important issue in design study of JSFR, because it may affect to structural integrity of the pipe. In this paper, numerical simulations for turbulent flow at Re=5×10^5 through the short-elbow pipe (Rc/D=1) which curvature radius Re corresponded to pipe diameter D was conducted to validate an in-house LES code named as MUGTHES for the pipe elbow flow and to investigate pressure fluctuation generation mechanism related to unsteady flow in a short-elbow pipe.

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Our research object is a cycloidal propeller that is equipped on airship. Cycloidal propellers have ability to control its thrust and direction very rapidly at the same time, so that high-performance thrust control can be expected to give airships more agility and various utilities. In this study, we report results of wind tunnel tests and flow measurements around a rotor by the particle image velocimetry (PIV) applying to a miniature cycloidal propeller. Our results showed that thrust coefficients decreased as advance ratios increased. Furthermore, it was clarified that cycloidal propeller intakes the air from axial direction of the propeller and vortex of counter-clockwise rotation was observed in the outflow of propeller by visualizing the air flow around the rotor by PIV.

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An axial-flow fan causes anomalous phenomena such as rotating stall and surging. From past researches, it has been found that casing treatments are effective in order to avoid these anomalous phenomena. The aim of this study is to verify effect of a self-circulation on the performance of an axial-flow fan. In this paper, the correlations between discharge and pressure, discharge and efficiency for total pressure are shown in each case of casing treatments. It is found that the casing treatment with holes is effective to delay the stall point and self-circulation is effective from the viewpoint of efficiency for total pressure. It is suggested that the self-circulation is preferred as long as both delaying stall point and efficiency for total pressure should be concerned.

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Closed-type centrifugal pump with single-blade is used as a sewage pump widely. However, closed-type single-blade centrifugal pump impeller is acted on a large thrust during the pump operation because the impeller is an asymmetry geometrically. In addition, the hydrodynamic force is expected to act outside of the rear shroud and the front shroud in the closed-type impeller. Therefore when the reliability of the pump is secured, it is necessary to grasp the hydrodynamic force quantitatively and elucidate the behavior. This study investigated behavior of the radial thrust, consideration of the leakage flow outside of the rear shroud and front shroud. As a result, the effect of the leakage flow outside of the rear shroud and front shroud on the radial thrust was clarified.

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In field of microfluidics ,it is required to control die flow of liquid at micro or nanoliter volume levels accurately. By using a ferrofluid, the flow of liquid in a microchannel can be controlled by die driving power exerted on the ferro fluid. Hie purpose of study is to investigate die movement of ferrofluid and liquid slug in a capillary tube under magnetic field. The external magnetic field is used to control ferrofluid. However, the study with a ring permanent magnet is not almost done in this field. In this study, flow of ferrofluid and pulled liquid slug have been investigated in die capillary tube under magnetic field generated by die magnet As a result of observing the motion and behaviour of die ferrofluid, die magnetic field exerts an influence on movement of ferrofluid. In addition, die viscosity of liquid slug affects die variation of velocity remarkably.

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In recent years, considerable research efforts in a number of institutions have been devoted to advancing understanding of the unsteady effect, because the effect of unsteady fluid forces must be important to the flight mechanism. In the present study, the unsteady fluid forces and vortical flow field were measured during upward movement by changing the angle of attack impulsively in a wind tunnel test. In order to better understand the relationship between unsteady fluid forces and the three-dimensional vortex behavior, a PIV technique in a scanning light-sheet in the spanwise direction was also used to examine the flow field around the airfoil. The unsteady fluid forces were affected by the vortex behavior on the upper surface of the airfoil during upward movements.

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Our aim is to clarify the propulsion mechanism of dolphins and fish and to investigate three-dimensional (3D) vortex structure in the wake of a tail fin. In this study, we replaced the pitching motion of a tail fin by an oscillating wing with a drive unit. Flow fields around the wing were measured by using stereo-PIV. To construct the 3D structure of the vortex in the wake, we determined the flow fields in cross-sectional planes spaced by an equal distance. We reconstructed the field of three components in 3D from the velocity data with three components in 2D. We visualized 3D vortex structure by calculating vorticity from this velocity data and plotting iso-vorticity surface. From the visualized result, the vortex ring was found to occur by the motion of kick-down and kick-up of the wing.

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Gas circuit breaker is the very important safety device that instantaneously intercepts the circuit and protects the instrument when an abnormal current like lightning flows to electric power transmission line of high voltage transformation installation. Recently The miniaturization needs of the instrument builds up as a high glasshouse effect of SF6 is feared and the quantity consumed reduction is requested. In this study, we analyzed the behavior of the high temperature gas in consideration of three dimensions in gas circuit breaker,using CRIMSON(Civa Riflned Multiphase SimulasiON). And we thought separation of fixed electrode and movable electrode to attempt the improvement of interception performance prediction technique.

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Compression ignition characteristics of dimethyl carbonate (DMC) and the influence of DMC addition on diesel fuel HCCI combustion were investigated using a single cylinder experimental engine. Numerical analysis based on detailed chemical reaction model was also conducted to understand the oxidation mechanism of DMC/diesel fuel HCCI combustion. As the result, it was experimentally confirmed that heat release in HCCI combustion delayed with DMC addition, but HCCI operation range was not extended. The numerical analysis showed that DMC inhibits the low temperature oxidation reactions (LTR) of diesel fuel, because OH is consumed by reaction with DMC. By adding a DMC to the diesel fuel, the LTR exothermicity is reduced, and the reaction appearance timing is retarded.

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Recently, the internal combustion engine are require to use alternative fuels and to improve the thermal efficiency because of controlling escalating prices of crude oil and reducing carbon dioxide emissions. We propose DME hybrid engine which can solve these problems at the same time. DME can be made from various resources. At the start up and low load, this engine is operated on the compression ignition using high cetane number of DME. While, at the middle and high load, it's operated on the spark ignition fueled by hydrogen and carbon monoxide reformed from DME. The latter can recover the exhaust heat using the endothermic reaction. In conclusion, this engine is improved the thermal efficiency by reducing pumping loss at the low road, increasing the compression ratio utilizing the high self ignition temperature of reformed gases, burning lean mixture by hydrogen enrichment, and recovering the exhaust heat. In this report, we researched the exergy efficiency and the output characteristics at the spark ignition operation.

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Observations of DME spray in a constant volume vessel under CI engine-like density conditions were conducted to understand the breakup and atomization behavior in the near-nozzle field. Ultra-high speed and microscopic images of DME spray were obtained using a combination of a telescopic lens and short exposure time of 18nsec with nano-flash-light. As a result, fuel droplet and breakup were not observed, unlike diesel fuel spray. The outer edge of the spray with large turbulence was break off from the main spray and rapidly evaporated. The contraction flow at injection nozzle outlet was not observed.

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To understand the lubricated condition between slipper and swash-plate, the slippers behavior was measured by the test rig. In addition, simulation model of slipper behavior was constructed. The hydrodynamic analysis of oil-film between slipper and rotational plate was coupled with multibody dynamics of piston assembly. The result of the analysis shows good correlation with experiments when we take into account the shear drop of the edge of slippers.

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The slippers behavior in swashplate-type axial piston motors was measured by the test rig. The operating conditions were supply pressure of up to 35 MPa and rotational speeds of 0.0-26.7rps. The displacement between a slipper and a rotational disk, tilt angle, azimuth angle of a slipper and frictional torque are reported. As the rotational speed increased, the displacement and the tilt angle increased. As the supply pressure increased, the slippers center displacement, the tilt angle and the azimuth angle decreased, and the frictional torque increased.

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This study is aimed at development of the extra-low head water turbine for an open channel from a viewpoint of using effectively unused hydropower energies, such as an irrigation channel. Then, paying attention to the cross-flow runner, authors eliminated the casing and tried the application as a water turbine for an open channel. In this paper, water turbine performance, the flow situation characteristics, and the flow in the runner were experimentally investigated about effect on the shape of water turbine. The results showed that an output and turbine efficiency of straight blade is better than curved blade.

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The hydrosphere environment has kept of good conditions naturally by biological purification. However, the natural purification system cannot be maintained anymore in accordance with a dramatic change in life style of modern human society. Therefore, we focused on a water quality depuration system with the aid of micro bubbles. In the present study, we considered the abrupt change of diameter, Ph value and dissolved oxygen value (DO) just before and after generating micro bubbles using a pressurizing dissolution method.

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This paper proposed a new method for evaluation of cavitation erosion in hydraulics based on CFD (Computational Fluid Dynamics) and experiment. A simulation model is made, which has same geometry of a submerged jet experiment system. According to the analysis of flow and pressure distribution characteristics from CFD and the erosion map in experiment, it is found that die erosion has close relationship with the distribution of cavitation number σ which is calculated from flow and pressure. The relation makes possible that with only calculating the distribution of σ on surface of specimen by CFD, the erosion risk can be evaluated. Erosion map for different jet distance are predicted with the method, and they fit well with erosion experiment results.

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Recently, the microcapsule technologies have been paid a lot of attention in various fields such as foods, printing, medical science and many other industries. On the contrary to its popularity, its production and controlling have still been a focus of study. In this research, authors used the orifice method, which has many advantages in production as well as a drawback of being difficult to make smaller sized microcapsule, and tackles the drawback with a boundary tension-applied technique. As for the controlling, authors focused on the fact that the microcapsule behavior has not been fully understood and tried to observe and analyze its behavior by way of CCD camera aiming at controlling capsule movement in a capillary tube.

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In the case of unexpected tube failure of steam generator (SG) in sodium-cooled fast breeder reactor (SFR), the exoergic reaction between liquid sodium and water/steam produce reaction field (reaction jet) with high temperature and high corrosive (sodium-water reaction). Adjacent tubes exposed to the reaction field and have possibility of wastage by erosion-corrosion action and of overheating rupture by inner pressure with reduction of material strength. It is integral for safety evaluation to predict the event with high accuracy that we understand behavior of sodium-water reaction inside SFR SG in detail. Sodium-water reaction test has been carried out using steam generator water/steam leak test facility (SWT-3R) under full-power operation condition. As the result of present study, we confirm the temperature distribution, the tube failure region and the event progress in sodium-water reaction.

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In case of the water leak into sodium in a steam generator (SG) of sodium-cooled fast breeder reactors (FBRs), exothermic reaction produces reaction fields in association with high temperature and high corrosive action (sodium-water reaction). Adjacent tubes are damaged due to erosive and corrosive environment of the reaction field. Therefore, it is integral to evaluate such sodium-water reaction phenomena with high accuracy for the safety assessment of FBRs. For the purpose of understanding the wastage mechanism, we developed the new experimental apparatus and established the test procedure in which sodium hydroxide (NaOH) collided with the tube material under high temperature conditions simulating the reaction field.

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The aim of this study is to control micro-bubble diameter. The micro-bubble is generated by means of injecting gas through spinning porous plate. In the study, we report the influences on micro-bubbles by surface tension, surfactant concentration and circumferential velocity of the micro-bubble generation area. By increasing circumferential velocity, the diameter of bubbles decrease. Also as surface tension is lower by increasing surfactant concentration, the diameter of bubbles is decrease. However, under the condition of surface tension is constant, the diameter of micro-bubble doesn't decrease with overmuch surfactant addition. It is proved that the diameter of bubble depends on the surface tension and circumferential velocity.

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Analysis for natural convection heat transfer between parallel flat plates was conducted to develop a thermal insulation system. The heat transfer and fluid flow were analyzed to develop an optimum thermal insulating architectural structure. The optimum vent layer size and the optimum cross-sectional shape of thermal insulation system were investigated with the numerical simulation. The vent layer size and the cross-sectional shape were considered along with developing the technique how to control the present thermal system by switching the vent.

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The thermo-physical property of Erythritol which is one of the phase change latent heat storage materials is elucidated in order to consider the temperature dependency. The heat transfer of natural convection is also investigated in a horizontal enclosed rectangular container filled up with Erythritol under the conditions of undersurface heating and upper surface cooling.

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Superheated steam is one of the most popular heating device in food processing. The drying sweet potato is specialty products in Hitachinaka area. The purpose of this study are to investigate thermophysical property of sweet potato. We compared the heat-transfer characteristics of micro-heater and superheated steam. Furthermore, we evaluated the heat transfer and thermal conductive capabilities using two heating equipments. The heat transfer coefficients and the thermal conductivity of sweet potato were determined by using heat flux sensor and thermocouples. The surface tissue configuration of heated sweet potato was observed by using electron microscope. As a result, we obtained the temperature distribution and heat property. The experimental results indicated the effectiveness of heating method for sweet potato.

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In a T-junction mixing part of two fluids without the temperature differnce, the behavior of a jet flow was examined in the case of the flow with a obstacle. The flow was visualized by dystuff and vorticity obtained base on the velocity field by PIV. There was controlling effect of the vortex in case of the main fast flow velocity when the obstacle is put on the downstream place from the branching tubule. When the obstacle is put on the upstream part of branching tuble, it is understood that the vortex is generated away from the wall.

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The adhesive strength of strontium apatite (SrAp) films and the cell attachment of human osteosarcoma cell line Saos-2 on the films were investigated. SrAp was coated onto substrates using radio frequency sputtering. The coated films were heated or subjected to hydrothermal treatment. The crystallinity and the surface of the films were observed using X-ray diffractometer (XRD) and a scanning electron microscope (SEM), respectively. The adhesive strength was measured using a pull-out test and the cell attachment was carried out with the osteoblast-like cells. From XRD patterns, as-sputtered film at gas pressure of 0.5 Pa was high crystallinity. In pull-out tests, the results indicate that the adhesive strength of the film increased after the hydrothermal method. In the cell attachment measurement, the number of cells and the cell area on the SrAp film treated with the hydrothermal treatment were higher than those on the as-sputtered SrAp film. Furthermore, the number of vinculin-positive focal adhesion plaques on the film was greater than hydroxyapatite coated films.

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We have proposed an adhesion method by using integrated low-level energy sources of heat, vibration and pressure. This adhesion method is expected to be applied to adhere biological tissue to the metal specimen such as stent-graft and blood inlet cannula of ventricular assist devices. Shear tensile tests on porcine aorta adhered to stainless steel were performed to determine the relationship between adhesive strength and adhesion conditions, such as pre heated temperature at heater tip, method for applying heat to biological tissue and stainless steel. The average adhesive strength was 0.148 MPa under the condition with pre heated temperature of 200 ℃, on adhesion time 120 seconds, on adhesion pressure of 2.5 MPa, in the heating from stainless steel. The adhesive performance was found to be improved by applying heat from metal in adhesion biological tissue to metal.

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The research and development of Left Ventricular Assist Device (LVAD) is hoped as a cure for seriously ill heart patient We developed an enclosed-impeller axial flow blood pump for a LVAD. However, this pump has serious problems of hemolysis. The factor of main hemolysis is surface characteristic of the vane which is a blood contact surface. Therefore, we paid attention to a hydrcgenated amorphous carbon (a-C:H) film. Recently, a-C:H film is expected as biomateriaL The purpose of this study, the hemolysis performance is improved by a-C:H film. a-C:H film was deposited a radio-frequency plasma Chemical Vapor Deposition (CVD) technique. The hemolysis was compared using the coating vane and pure vane. As a result of hemolytic examination, a-C:H film coating reduce the hemolysis performance. From this thing, a-C:H film coating reduce the hemolysis performance.

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Currently, magnetic/fluorescent composite materials are attracting a great deal of interest for the imaging modality in-vivo because they have many excellent features for luminescence phenomenon and magnetic response for external applied magnetic field. However, they have prepared by mixing magnetic particle and fluorescent particle. Therefore, it has problems such as increasing of particle size and shape. We succeeded in fabricating magnetofluorescent silicon nanoparticles including the magnetic components into the particles which can be controlled transport by external applied magnetic field. The magnetofluorescent silicon nanoparticles not only showed green fluorescence by controlling the particle size less than 3.0 nm but also provided efficacious biocompatibility.

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Nitrogenated diamond-like carbon (N-DLC) films have more attention for biomaterials because they have excellent biocompatibility. It is not enough to apply them to the biomedical device to their inadequate adhesion property between the films and polymer substrates. To solve the problem, we have proposed the multi-layer of DLC and N-DLC films on the substrate. The films were evaluated by Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and contact angle measured. The cytocompatibility has been investigate under cell culture using NIH-3T3. It was found that the multi-layer of N-DLC/DLC was able to improve both adhesion property and biocompatibility.

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Metals such as titanium materials and stainless steel are widely using in orthopedic implant devices. In this work, the authors examined the application of thermoelastic stress analysis for fatigue properties of implantable metals. The fatigue test with Ti-6Al-4V alloy and stainless steel was conducted with sine wave at stress ratio (minimum stress/maximum stress) =0.1. The effects of wave frequency and materials on the difference of surface temperature (ΔT) obtained by thermoelastic stress measuring method were examined at various applied stress using Ti-6Al-4V alloy and stainless steel. The AT for Ti-6Al-4V alloy and stainless steel increased with increasing applied stress. Effect of frequency on AT was also small for Ti-6Al-4V alloy and stainless steel. Surface stress calculated with thermoelastic parameter was also close to applied stress. It was clear that thermoelastic stress measuring method is useful for estimation of surface stress of orthopedic implant devices.

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A 5-DOF self-bearing motor has been proposed to achieve a compact active magnetic bearing (AMB) system. The 5-DOF self-bearing motor possesses the functions of a motor, two radial AMBs, and an axial AMB. Therefore, it is possible to downsize the AMB system with maintaining high performance. In this paper, interior permanent magnet (IPM) type 5-DOF self-bearing motor is proposed. It is analyzed to realize the further downsize for the application of an artificial heart using 3 dimensional finite element method. The analytic condition is set that the motor torque is 30mNm, the control force is quintuple of the rotor gravity (5G). The optimization result shows the sufficient miniaturization for an application of the artificial heart pump.

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Active magnetic bearing (AMB) system can support the rotary object by magnetic attractive force without any contact. This paper introduces a new 5-axis controlled magnetic bearing system with permanent magnet biased radial and axial hybrid magnetic bearings applicable to wide gap and ultra low temperature fluid pump. The fundamental characteristics of the radial and axial magnetic bearings are analyzed by magnetic field analysis using finite element method. The experimental setup is fabricated and the characteristics are measured. The results of the proposed magnetic bearing system show good control capability.

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Many groups in the world are trying to develop many kinds of artificial heart for severe heart failure patients. We adopted a magnetically suspended motor which contributes device durability and better blood compatibility for the ventricular assist device (VAD). The influence that the size of permanents into the magnetic bearing system gave to the bearing performance was examined in detail by using the numerical magnetic field analysis. The double-bias hybrid magnetic bearing consists of four electromagnets located 90 deg intervals, three ring-shaped permanent magnets and a yoke. The results of numerical analysis show that the size of permanents in the same direction as flux path affects the bearing performance greatly. The comparison between numerical analysis and experiment results indicates to establish design parameter of double-bias hybrid magnetic bearing.

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