Clean, excellent in quiet Stirling engine is taken up, and it aims at the development of the Stirling engine generator that uses the hot spring heat. In this study, we have confirmed power generation by the low temperature degree heat source of about 70℃ according to a small test model of the γ type. Additionally, we calculate for the design of an experimental prototype. As a result of the calculation that used the Schmidt theory, the influence of a temperature ratio and an invalid volume ratio, the optimum value of the phase angle, the value of indicated work 0.77J and the value of indicated power 1.29W were derived.

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Interferometric temperature measurement around an isolated boiling bubble was conducted for studying heat transfer from liquid phase to the bubble. Finite fringe interferogram was captured with Mach-Zehnder type interferometer and a high-speed camera. Brightness distribution in the interferogram was converted to series wrapped phase image and axisymmetric differential temperature image through wrapped phase image, differential phase image, unwrapped phase image, and differential refractive index image by the Hilbert transform and Abel inversion. The resulted differential temperature image shows that the superheated liquid layer on the heating surface is lifted up and stretched by the growing bubble, and that hot liquid flow is accompanied by departed bubble.

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Microbubbles are utilized in various engineering fields. However, measurement techniques of void fraction which is important parameter in gas-liquid two-phase flow is not establish for dispersed bubbly flow with microbubbles. In the present study, the void fraction in bubbly flow is measured with Constant Electric Current Method. This method was used for a liquid film an annular flow in previous studies. In order to measure the void fraction in bubbly flow by this method, new calculation method of void fraction from electric signals was suggested. In this experiment, the void fraction in bubbly flow with microbubbles generated on the microbubble generator with a venturi tube was measured by Constant Electric Current Method and using void calculation methods. In the comparison of new calculation method and previous methods, void fraction in bubbly flow with microbubbles can be estimated more accurately by new calculation method.

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Simultaneous measurements of micro thermal analysis and mass measurement were demonstrated with a cantilever type MEMS calorimeter. The fabricated cantilever type MEMS calorimeter having low heat capacity and high thermal resistance can conduct nano-gram level thermal analysis with high speed temperature scan. Furthermore, mass of the order of nano-gram is available using the mechanical resonance of the cantilever. Dehydration process of sub-micro-gram CuSO_4・5H_2O was simultaneously analyzed in a SEM, stepwise mass reduction and corresponding endothermic peaks were observed. Sublimation process of tiny Menthol was also analyzed in the air. In an intermittent series temperature scan, stepwise mass reductions of nano-gram order and sublimation heat peaks in the DTA curve were observed.

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In a case of complete wetting, a very thin film spreads ahead of the macroscopic edge of the droplet on a solid surface. This thin film is called precursor film. The precursor film plays a key role in many practical processes, such as micro heat pipe, thin-film coating and oil recovery. The authors carry out experimental works focusing on the spatio-temporal growth of the precursor film at an early stage of the droplet spreading on the substrate. Simultaneous observations of the macroscopic and microscopic edge of the droplet by Brewster angle microscope enable ones to detect the precursor film at a growing stage. For the film thickness, the authors employ a confocal laser displacement sensor to measure temporal variation in thickness of the precursor film at a designated point.

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Steam injector is a passive jet pump which operates without rotating power source or machinery and it has high heat transfer performance due to the direct-contact condensation of supersonic steam flow into subcooled water jet, and it has been considered to be applied to the passive safety system for the Next-generation nuclear power plant. The objective of the present study is to investigate the effect of interfacial behavior on heat and momentum transfer characteristics between the flows. In the present study, the interface of the flows was observed with high speed video camera and wavy behavior on the water jet surface was quantified with image processing technique and correlation method. It was confirmed that there were significant correlations between interfacial behavior and heat transfer characteristics, which was described with the relation between Nusselt number and nondimensional wave velocity.

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Fine particle size measurement technique with laser interference fringes is proposed as one of the in-line measurement techniques to the diameter of several hundred nano meter particles. The objective of this study is to examine the principle of this measurement technique with laser interference fringes. First, we visualize the laser interference fringes images with a high-speed video camera. And we identify the fringes images moving through the test cell. Finally, we measure the time variation of the intensity of the laser interference fringes by using photodiodes. It is confirmed that the voltage signal depends on fine particle size. Also, correlation between the time and the voltage signal scattered with the focused laser beam is different from that of with the parallel laser beam.

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To keep a stable operation on a high level waste glass melter, it is necessary to observe the distribution of platinum group metals in molten glass. Electrical resistance tomography (ERT) has a potential to visualize the inside of the melter section because ERT can apply at the severe conditions such as high temperature and radioactive fields. As a result of applicability study, an acceptable image can be reconstructed at the cone shaped vessels, such as lower part of a glass melter. Although this method has a limitation dependent on the concentration of platinum group metals in molten glass, it is applicable at the all of the actual operating range of glass melter.

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In order to achieve increase of power outputs of a BWR, it is extremely important to evaluate coolant flow in a lower plenum. Numerical simulation is helpful to predict the coolant flow. However the simulation results considerably depends on models, thus verification experiment is needed. Hence, the objective of the present study is the construction of the benchmark of CFD code by conducting experiments and to clarify the flow structure of a lower plenum in detail. We constructed a 1/10 model of a lower plenum to measure velocity, differential pressure profiles and to visualize the flow structure. In the experiment, it turned out that flow structure of the lower plenum vary depending on Reynolds number. Therefore, it is necessary to examine the effects of complicated phenomena on such transition of the flow structure.

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Temperature is one of the concern parameters particularly in plastic injection process. This paper introduces the new application of Electrical Capacitance Tomography (ECT) as a non-intrusive, non-invasive technique in determining the temperature distribution on a polycarbonate material. The objective of this study is to tract the intensity of temperature as it's distributed during the phase change of polycarbonate resins. Polycarbonates have been placed inside the container with 12-electrodes circumferentially mounted onto it while the other ends of the electrodes are connected to ECT. The container was heated with a given period of time. The relative permittivity has been determined by ECT and out of it, temperature calculations were performed. The results of this work give emphasize the relationship of temperature and relative permittivity which was found inversely proportional to one another. ECT is suitable in measuring not only electrical properties of a certain material but also in determining temperature distribution.

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Understanding of detonation phenomena is important on physical hazard analysis of high-energetic materials. This paper describes our study on the estimation method of the thermodynamic state variables for simulating the detonation phenomena by CFD code.

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The combustion phenomena of high energetic materials, which accompany the rapid production of much amount of gases and heat, have been focused on in the fields of automobile safety application such as airbag system. This paper describes our study on the combustion characteristics and combustion model of gas generants for airbag inflators.

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To understand the consequence of accidental gas explosions in an open space, the effects of flame propagation behavior on the blast wave were examined experimentally. The spherically propagating flames in the mixtures of methane and hydrogen with air were focused. The results show that the flames at equivalence ratios of 0.7, 1.0, and 1.3 were intensively wrinkled and accelerated with the increases of hydrogen addition in methane/air mixtures. The overpressure of the blast wave tends to increase acceleratingly by the flame wrinkling. The flame winkling is considered to be generated by diffusive-thermal instability according to the analysis of the Effective Lewis number. The overpressure can be predicted by the acoustic theory which indicates that the intensity of blast wave is affected, in particular, by burning velocity, volumetric expansion ratio and the flame acceleration. Especially, the intensity of the blast wave is strongly affected by the acceleration of the burning velocity.

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The interaction between the shock waves and particulate materials was numerically investigated using the gas/particles two-phase flow simulation codes, in order to predict the performance of the blast mitigation method with particles. Simulations of the shock tube containing the glass/water particles were carried out, and the simulated results showed that the water-like particles provide the larger shock pressure mitigation effects than the glass particles. In the spherical burst, the blast pressure mitigation effect varies largely with the diameter of particles surrounding the explosion center.

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On nuclear fuel recycle, recycling solution is heated. Because of heating, flow instabilities that rapid evaporation and reflux of water could happen. It could scatter radioactive substance. Therefore we should prevent rapid evaporation of water. In this study, it is investigated occurrence condition and the action on experiment. Working fluid is water. Vertical tube,ID=6mm, 1500mm length. Working fluid is heated under the vertical tube by sheathe heater. The influence of condition of heat and temperature of water on the vertical tube is evaluated on condition of the phenomenon occur. As a result, difference of the phenomenon occur, periodicity and pressure in vertical tube were observed.

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Initiation and propagation characteristics of a detonation in an extremely narrow gap were experimentally studied using a soot-foil-pattern technique. In the experiments, we used stoichiometric propane-oxygen-nitrogen gas mixtures, where dilution ratio was varied as a governing parameter. A narrow gap, whose height was varied as another governing parameter, was installed inside a large reaction chamber. The reaction chamber was filled with a premixed gas mixture at the ambient conditions of temperature and pressure, and the gas mixture was ignited on an inner wall of the reaction chamber. When a flame went into the narrow gap, a detonation was initiated in the narrow gap in some conditions. Especially, in some highly-diluted conditions, a detonation was initiated in the narrow gap whereas no detonation was initiated outside the narrow gap in the reaction chamber.

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The detonation propagation phenomenon in a bend has not yet been sufficiently understood due to its complexity. In order to examine the detonation propagation in a bend, the detonation waves of a stoichiometric ethylene/oxygen mixture gas propagating through rectangular cross-section bends with different inner radii are visualized. The cell structure and wave front shape of the detonation are observed simultaneously using a new visualization technique developed in the present study. The ratio of inner radius of bend (r_i) to detonation cell width (λ) is an important factor determining the detonation propagation characteristics in the bends. The detonation propagation mode transitions from unstable to stable in the range 20 ≤ r_i/λ ≤ 33. The cell structure and smooth wave front of the detonation can be sustained in the stable propagation, however large-scale collapse of the cell structure and fluctuation of the detonation wave front shape are observed in the unstable propagation.

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The detonation propagation in 180deg and 360deg bend tube was numerically investigated using two-dimensional Euler equations with a one-step chemical reaction model governed by Arrhenius kinetics. This paper describes the effect of curvature radius of inner diameter (R=37.5L_<1/2>, 200L_<1/2>, 450L_<1/2>) and activation energy (Ea=15, 20, 25, 30, 38.2, 45) on the detonation configuration in the bend tube (the tube width fixed W=150L_<1/2>). At the low activation energy, the detonation propagated with constant configuration, and the high pressure belt was generated near the outer side at R=200L_<1/2>,. The higher activation energy induced unsteady features due to the irregular collision of the triple points and the expansion effect. At the small curvature radius, the detonation propagated on the outer side and fell on the inner side. In the failure configuration, the curved shock wave and combustion wave propagated connecting to the outer detonation.

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We have developed a design support system, "Design Support Navigator", for young mechanical engineers. This system supports a design of machine elements at a planning phase. We have educated them about design of screw fastening by using this system. The lecture contents are (1) How to use this system, (2) Outline of design flow, and (3) Selective exercise of important points. Remaining contents studied by oneself after the education. By this means, they make better use of their time. According to course evaluation, the contents of this education were appropriate basically. This system will be utilized to an elementary design at a planning phase.

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Educational method of industrial subject is one of the subject to aquire a teacher certification of technical high school. I've been taking charge of this class in Keio University faculty of science and technology since 2004. The historical transition of the course of study, and a curriculum of industrial subject are treated in the class. Moreover, the teaching practice concerning the machine cource is mainly treated in the class. Students are evaluated with the report that relates to the course content. This paper describes these educational practices and educational meanings of this subject.

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Promise rates of employment of students (High school, University, College, College of Technology and Specialized Training College) at Oct. 2010 are introduced. It is found from these data that the promise rate of College of Technology is most high among various colleges and university. The characteristics of College of Technology are introduced and discussed by using an OECD report etc..

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International rankings of universities, institutes and colleges are offered by various institutions around the world. The current paper mainly discusses the assessment of Japanese universities made by THE QS World University Rankings.

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Homogeneous Charge Compression Ignition (HCCI) combustion offers the advantages of high efficiency and low emissions of pollutants. However, the characteristics of HCCI combustion can prevent suitable engine operation owing to the rapid combustion process that occurs accompanied by a steep pressure rise when the amount of fuel injected is increased. In this study, we analyzed effects of engine speed on combustion characteristics in an HCCI engine based on experimentation with actual engine. In addition, we analyzed the details of combustion characteristics by using numerical analysis of elementally reactions. As a result, cool flame reaction was moderated by increasing the engine speed.

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The homogeneous charge compression ignition (HCCI) combustion has attracted much interest because it can simultaneously achieve high efficiency and low emissions. However, it is difficult to control the ignition timing with this type of combustion. The HCCI combustion process also has the problem that combustion proceeds too rapidly under high load operation. Supercharging the intake air is one of the effective methods for increase the operating load of HCCI combustion. In our previous studies, the heat release rate of hot flame can be moderated by using supercharged HCCI combustion. In the present study, a blended fuel of dimethyl ether (DME) and methane, with each component having different ignition characteristics, a supercharged HCCI combustion were used to investigate the effects of the mixing fuel ratio and injected heat value on the heat release characteristics of the hot flame

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In this study, we experimentally investigated the effects of burnt gas jet ignition on ethanol spray combustion using a constant volume combustion vessel with a sub chamber. The ignition and combustion phenomena were observed by using a high-speed video camera, and combustion pressure history was measured as well. In case of burnt gas jet ignition, compared with a conventional spark plug ignition, stronger luminous flames were observed, and rate of pressure rise and maximum overpressure much increased. Moreover, it was confirmed that measured HCHO concentration of the burnt gas in the combustion vessel remained at low level although the amount of ethanol related to combustion reaction increased. It is mainly due to the strong turbulent mixing effects of the hot burnt gas jet and the spray flows.

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As a new method to improve the capability of flame holding of jet diffusion flame, a coaxial double-injector burner, in which small amount of rich premixed gas is injected from the gap between the injector tubes, was developed. By using this method, a jet diffusion flame of pseudo biogas (methane diluted with nitrogen by 70%), which cannot be stabilized on an ordinary injector because of its weakness of reactivity, was easily stabilized against a considerably high injection velocity of fuel. It was found that the addition of premixed gas at the flame base forms a premixed flame "wing" connected to an ordinary reaction kernel, which stands a high flow velocity because of its high propagation velocity.

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Stabilized three-stage oxidation and its pressure dependence of stoichiometric n-heptane/air mixture were examined using a micro flow reactor with a controlled temperature profile. Especially at low velocity condition, three weak flames were observed as spatially separated flames in the different temperature ranges, and these flames correspond to low-temperature reaction and separated high-temperature reactions. As increasing pressure, the first and second flames got stronger whereas the third flame got relatively weakened. Reaction path analysis and sensitivity analysis were conducted to get a better comprehension of such pressure dependence. The results showed that the reaction rate of the third flame depends on that of CO and H_2/O_2 reactions, thus second explosion limit of H_2/O_2 plays a key role in the pressure dependence of the third flame.

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Influence of the excess air for the methanol auto-thermal reforming was investigated experimentally. Catalyst temperature and H_2 flow rate of reforming gas were measured for φ<1.0. When φ is changed from φ=1.0, the catalyst temperature gradually increases until φ=0.6. It indicates that POX selectively occurs with methanol. At φ=0.5, all methanol reacts with excess air by POX. When φ is decreased from φ=0.6, catalyst temperature keeps constant because no methanol is left, with further decrease in φ, the catalyst temperature increases once again because the excess air reacts with reformed H_2 as a combustion.

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Hydrogen formation and purification by methanol steam reforming and the Pd/Ag hydrogen separation membrane were investigated experimentally. Hydrogen permeation rate increases with increasing total pressure of the reformed gas, while it is independent from methanol flow rate. When the methanol flow rate is increased, the hydrogen concentration boundary layer over a separation membrane become thinner and the permeation rate of hydrogen increases, which recovers the decrease in the permeation rate of hydrogen due to a decrease in the hydrogen partial pressure in the reformed gas. These tendencies are estimated well by taking into account of the decrease in the partial pressure of hydrogen at the separation membrane due to the hydrogen permeation.

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Although semiconductor device has been developed by design rule scaling and wafer size enlarging, there are still many difficult challenges such as new material introduction, 3D integration etc. Problems and developments in 45nm device are introduced herein as Paradigm Shift 45. Now is the time to challenge 20nm devices. There are many new challenges in 20nm device such as thin and conformal liner integration. Etc. Those problems are introduced as Paradigm Shift 20.

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The three dimensional cross-sectional particle concentrations of particle-liquid two phase flows in the two cross-section of microchannel has been reconstructed using process electrical capacitance tomography (ECT) method. The capacitances between 12 multilayer electrodes in the two cross-section of the microchannel are measured by a high speed multiplexer and a capacitance measurement system. The comparison between the qualitative result of 3D reconstruction image and the quantitative result of particle concentration in flow direction transition is that the particle is reasonably distributed in the particle injected area of the cross-section. Also, cross-sectional images of the particle distribution of particle-liquid two phase flow are compared to results obtained from computer numerical simulations. The cross-sectional particle concentration calculated by the Eular-Lagrangina numerical simulation reasonably agrees with that from the 3D reconstruction image by ECT.

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The ultrashort pulsed laser has widespread applications in fields such as biomedical research, micro machining, ultrafast optical communications, and so on. Among the various ultrashort pulsed lasers that have been developed, ultrafast pulsed laser with single-wall carbon nanotube (SWCNT) saturable absorbers (SA) have recently received considerable attention. However, the effect accompanies heatup of SA materials because the absorbed light energy is converted into thermal energy; thus, SA devices could suffer from damage due to heatup. Therefore we have proposed the concept of attaching a nanostructured heat sink to the SWCNT saturable absorber. In this experiment, SWCNTs were embedded into nanopores of a porous alumina matrix (PAM) that could provide excellent thermal conductivity and optical transparency. Furthermore, we demonstrated the mode-locked operation of an Er fiber laser with the developed saturable absorber.

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This experimental study aims at measurement concentration of jet diffusion. The hot wire concentration sensor to measure the concentration of components in binary mixture of gases is described. The concentration sensor consists of a concentration probe, a vacuum pump, a hot wire amplifier. And the concentration probe consists a brass sonic nozzle, a brass tube, tungsten hot wire to measure gas thermal conductivity of gas mixture. Now, this concentration sensor is produced by using the MEMS technology. This sensor is a composition on the chip such as a sonic nozzle, the micro channels, and the hot film sensors.

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In this study, tensile tests of transparent conductive oxide (TCO) deposited on polyerhylene naphthalate (PEN) films (TCO + PEN films) used in dye-sensitized solar cells (DSCs) were carried out. In order to discriminate AE signals in TCO from PEN films, PEN film specimens (TCO was removed by 17.5% acidum hydrechloricum) were also prepared. It was found from tensile tests that many AE signals were detected in TCO + PEN films, while few AE signals were detected in PEN films. On the other hand, the electric resistance of TCO was also measured during tensile tests. These results suggested that the critical damage in TCO was detected by the measurement of AE signals more sensitively than the electric resistance measurement. To identify AE sources, in-situ observation of specimen during tensile test with AE measurement was carried out. It was emphasized that AE behavior shows good agreement with the cracking behavior in TCO. Damages in TCO under mechanical strain were successfully monitored by AE technique in the present study. Consequently, it was suggested that AE technique could be a powerful technique for evaluating the damage accumulation process in DSCs.

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Non-uniformity of surface potential affects the generation of various defects such as particle adhesion, residues, and corrosion, during CMP process. The surface potential is caused from many factors like work function differences, electrostatic charges, and charged particles. We evaluate the surface potential change during CMP process by using EFM (Electrostatic Force Microscope) technique. The surface potential change was observed on contaminated insulators by polishing with a Si probe. The potential shift was different from the kinds of insulators, which indicates that contamination layer exhibits different properties. The potential shift was also observed on cleaned (without contamination) insulators; this result indicates that mechanical deformation arises surface potential shift like the piezoelectric effect of ferroelectric materials such as PZT.

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We focused on the fine particles motion being close to polishing surface in the CMP process of SiO_2 film, and then the fine particles motion was observed by evanescent field. In the case of ceria fine particles, the motion close to SiO_2 surface was observed. In the case of silica fine particles, the motion being close to SiO_2 surface was not identified. The cause was in the formation of the hydration layer on the surface by confirming the observation by use of the slurry of Wet/Dry state including the silica fine particles. Next, in the case of ceria fine particles and silica fine particles, the adhesion phenomena of fine particles to the surface were confirmed by FE-SEM observation. It is considered that the adhesion of fine particles to the polishing surface occurs in the CMP process of SiO_2 film.

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We used the atomic force microscope (AFM) technique to study fundamentals of Chemical mechanical polishing (CMP) as a polishing and monitoring apparatus. The AFM tip that spattered to mimic a single abrasive silica particle was used to evaluate the polishing rate in aqueous solutions. During the AFM scanning, such a spattered silica tip removed smoothly the organometallic complex layer of the copper surface formed in aqueous solutions and adsorbed the organometallic complex of the copper. The dynamic imaging method suggests a model for the copper CMP, in which the removal rate of the copper surface in the controlled oxidation process in BTA and Succinic solutions is faster than the process in Benzotriazole (BTA) solution only. The removal rate depends the thickness of the copper oxidation layer under the organometallic complex of the copper.

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The generating mechanism of micro scale local countercurrent flows and movements of dielectric particles in insulating fluid is investigated with a particle image analyzing and a particle tracking method. These flows and movements of particles are induced under an alternating electric field between parallel electrodes. And these particles movement generate some valuable flow structures. These flow structures are formed under high-electric-field intensity and low-frequency conditions, and are generated after the electric field inversion. This phenomenon has enormous advantages for a free abrasive polishing and a nanoscale green processing. In this study, the generating conditions of the electric field are classified and the generating process is revealed. As a result, it is important to generate the flow and the movement of particles that dispersed particles concentrate near both electrodes before the electric field inversion under high-electric-field intensity and low-frequency conditions.

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Influence of wafer notch on removal rate profile in chemical mechanical polishing process was investigated experimentally. As a result, removal rate close to the notch was larger than that far from the notch. Effective range of the notch was about 2.5mm from edge exclusion area in radial direction and was about 5mm from notch center in circumferential direction when the edge exclusion was 2mm. Therefore, the number of chips affected by the notch in CMP process is around 1 or 2 at most.

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The water flow was supplied from a nozzle on a rotating disk and the droplet formation process on the disk was investigated experimentally for the fundamental study of the water mark formation in CMP process. The rotating disk was made by an acrylic resin. The droplet formation process was observed by using a high speed video camera. Diameters of droplets remained on the disk were measured at various conditions of rotation speed and supplying water flow rate. As the results, it was found that the mean diameter of remained droplets became small with the increasing of disc rotation speed.

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