The purpose of this study is searching for a new method of dispersing spilled heavy oil, which has a detrimental effect on the natural environment and the ecosystem of the sea. A method ejecting a water jet vertically downward to heavy oil on the water surface was discussed. The water jet involved the heavy oil and the minute air bubbles, when it hits oil layer on water surface and passed the nozzle of a horizontal underwater guide plate. The shape of nozzles of the guide plate was three types; a conventional nozzle, a 5 times longer nozzle, and a taper nozzle. The dispersion efficiency of the taper nozzle was the best among three. The flow in the three nozzles was recorded by a high-speed camera. From the high-speed movies, the occurrence of two flows, normal and counter flow, was suspected in the taper nozzle. It seemed that the two flows (normal and counter flows) incresesed the sharing force between the minute air bubbles. It is considered that the sharing force increased the efficiency of disperse oil.

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This paper describes the numerical study of a non-stratified airflow over real complex terrain. Attention is focused on a mechanism of a local strong wind induced by a topographic effect. To reproduce the above-mentioned local strong wind, it was shown that the horizontal grid resolution from 50 to about 100m was necessary.

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Influence of incident flow conditions to tornado-like flow was investigated. In order to study the tornado resistance design for structures, it is necessary to reveal flow field of tornadoes. Because it was very difficult to evaluate tornado winds generated in real scale, a tornado simulator was developed in the laboratory and tornado-like flow was measured. The situation in which the form of the tornado-like flow changed depending on swirl ratio and surface roughness was reproduced, and the distribution of wind speeds according to this form became clear. These experiment results showed agreement with similar previous experiment results.

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The velocity and vorticity fields were measured in lower layer of a tornado-like vortex. Spiral bands converging on the tornado were found to be low speed streaks accompanied by horizontal vortices. These horizontal vortices were stretched, tilted and merged into the tornado. But, their circulation was quite small. The main contribution of the circulation to the tornado was horizontal shear occurred at the boundary of the low speed streak.

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We have tried to simulate various types of atmospheric turbulent flow with the multi-fan type wind tunnel in Miyazaki university in order to investigate wind effects on structures. This wind tunnel can easily generate low frequency fluctuation and form arbitrary mean velocity profiles through computer-controlling each fan. In this paper, we will introduce the flow-generating techniques of atmospheric boundary layers and a gust, and then show basic characteristics of the simulated flows.

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Effects of overlapped electric double layer and interfacial charge on the ionic transport in 30 nm rectangular nanochannel are numerically investigated in this study. The numerical code which can calculates the electric field and ionic distribution in nanochannel is developed based on the Poisson-Nernst-Planck equation using finite difference method. The validity of the numerical code is confirmed from the view point of electro kinetic potential and electric neutrality. At lower ionic concentrations, the numerical result deviates from the Graham equation due to the overlapped electric double layer. The ionic distribution, electric field and ionic current are analyzed at various KCl concentrations. The ionic distribution in nanochannel is strongly affected by the interfacial charge especially at lower ionic concentrations and K^+ ions increased in nanochannel due to the electric neutrality. As the result, the ionic current increases at the lower KCl concentrations from 0.10 to 0.40 mol/m^3.

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The aim of this study is to find a method to increase the interfacial area of two fluids in order to enhance mixing in a small scale channel. The investigation is carried out by an experiment as well as a numerical simulation. The matching between the results of the two methods is qualitatively good. Placing obstacles inside the cavity is found to be an effective method for mixing enhancement. It is shown that the concentration gradient at the cavity outlet can be used to predict the mixing in the downstream region. It is also shown that the technique used in the millimeter scale channel can be applied to a sub-millimeter scale.

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The Reynolds number of the flow in a micro fluidic device is low. Therefore, it is necessary to promote the mixing by some methods. This paper reports on the research to promote mixing by bubbles generated by an electric heater. We performed the visualization of mixing two fluids, colored with white and black paints respectively, in the micro fluidic device. Brightness of the fluid was observed with a CCD microscope. The image was analyzed with a personal computer, and the mixing rate was examined quantitatively. When microbubble emission boiling occurs on the heater, the mixing increased drastically. In contrast, the ordinal nucleate boiling did not enhance the mixing.

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A micro-channel with laser trapping system was fabricated to measure DNA rewinding rates of the enzyme (HsKu70). The HsKu70 with EGFP (fluolescent protein) was prepared in Ecoli., and the EGFP-HsKu70 was purified after the incubation. The fusion protein EGFP-HsKu70 is necessary for the direct visualization of the enzyme motion. A streptavidin-coated fluorescent bead was attached to λ-DNA, to capture the bead-DNA complex by an optical trapping for the measurements. The DNA unwinding rate of the enzyme can be obtained by measuring the distance between the trapped fluorescent bead and EGFP-HsKu70.

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HFOV is one of the artificial ventilation methods, and it is effective for medical care of newborn baby with respiratory disorder. The ventilation mechanism in HFOV is not simple, and Pendelluft is known as one of the gas exchange mechanism in it. However the experimental analysis of the flow structure of Pendelluft has not been carried out enough because of some experimental difficulties. In this report, the flow pattern of Pendelluft generated in a micro-channel with multi-bifurcations as a model of respiratory bronchiole has been investigated experimentally by time series measurement with micro-PIV technique.

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In the present paper, a new viscous micropump using rotor with groove is proposed. Its pressure characteristics are investigated by using a theoretical analysis and a model experiment. In the theoretical analysis, the two-dimensional lubrication theory for a straight duct is adopted. In the model experiment, the low Reynolds number flow in practical micropumps is realized by using glycerin as working fluid, and a centimeter-scale (not micrometer-scale) model pump is examined. With respect to the pressure characteristics, the theoretical results show qualitative agreement with the experimental ones. The pressure at zero flow rate obtained is quite larger than that of an existing viscous micropump.

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Various micro pumps are developed recent years. We have proposed a soft actuator that performs open-close movement and micro pump using soft actuator as a driving source. We have developed an soft actuator that perform open-close movement by arranging an soft actuator in which bimorph structures with anion-driven layers and cation-driven layers are connected and cation-driven layers arranged in face to-face relation. The authors have built up a micro-pump with the conducting polymer soft actuator that performs open-close movement as a driving source. Its oscillation volume can be adjusted in the range of 4〜47[μl/min]. Moreover, micro pump which used two actuators can transport flow in the range of 4〜39[μl/min].This micro pump which authors developed can work by low energy consumption.

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The effect of channel size on the characteristics of valve-less micro-pump with diffuser shaped element was investigated. The micro-pump consists of a diffuser shaped micro-channel and a chamber with a diaphragm, the vibration of which produces on oscillating flow. The pump performance of the diffuser type valve-less micro-pump with the cross sectional dimensions of 250μm×250μm was compared with previous data on 1mm×1mm micro-pump. The micro-channel was fabricated using micro fabrication technics. The measured maximum pump head and volumetric flow rate were 13.1mmAq at zero flow rate, and 0.2ml/min at zero pump head, respectively for the driving frequency 120Hz, and diaphragm deflection of 5μm. The pump head for micro-pump of 250μm is greater than micro-pump of 1mm.

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We employ the molecular dynamics method to simulate osmotic equilibrium of ideal solution and pure solvent separated by a semi-permeable membrane in a micro vessel. The validity of van't Hoff law in the system is examined for several values of concentration of solute in the solution. After introducing the motion equations for assemblies of solvent and solute molecules, we discuss stress terms in the equations.

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This paper reports an evaluation method on dynamic characteristic of thermal micro wall shear stress sensor. The sensor used in the present study is two-element type of Micro Flow Sensor (MFS). The sensors with four different shapes and two operation modes were tested. The channel is 1 and 2 mm in height and 30 mm in width. The pulsating flow in the channel was generated by a speaker, and the wall shear stress was measured by MFS and micro manometer. Inertia force in the pulsating flow with higher frequency includes the velocity delay near the wall. By compensating the velocity delay of pulsating flow, the measurement results by MFS agreed with the theoretical model. It is confirmed that MFS has a dynamic response up to 60 Hz at least and different dynamic characteristics depending on operation mode.

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A laser 2-focus velocimeter (L2F) was used for the measurements of velocity and size of droplets in a diesel fuel spray near the spray center 15 mm downstream from the nozzle exit. The micro-scale probe of the L2F was consisted of two foci and the distance between them was 14μm. The hole diameter of the tested nozzle was 0.113 mm and the injection pressure was 40 MPa. The light scattered by droplets was detected just after the spray tip reached the measurement position. It was confirmed that the rate of data-sampling should be increased to mega-hertz order for the measurement of a narrow distance between droplets after disintegration. Velocity and size of droplets decreased with the radial distance from the spray center. It was understood that the number density of droplets increased with the radial distance from the spray center in the spray core region.

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This paper describes a novel measurement technique for three dimensional shape of micro droplet utilizing micro LIF (Laser Induced Fluorescence) technique. A measurement system consisted of microscope equipped with 10x lens, high sensitive CCD camera, CW Nd:YAG laser, optical filters and so on. Calibration curve between thickness of micro droplet and emission of fluorescence dye solution was obtained by the use of the PDMS microchip, whose depth varied from 8 to 120μm fabricated using photo lithography technique. The calibration method provides high measurement accuracy and free from photo breaching. Measurement accuracy of the present method in depth direction was about 2μm assessed using laser displace meter and the spatial resolution in the x-y plane became 6.7μm. The technique is useful to investigate a two phase flow in micro scale.

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Micro bubbles are very small bubbles with diameters of 50μm or less, and have become to attract people's concerns rapidly attracted in the past several years due to their wide potential in practical applications to a variety of advanced technologies. However, the characteristic and the behavior of the micro bubbles have not been completely clarified yet. In this study, the compact and low power micro bubble generator has been developed, and the effect of electrical property of micro bubbles on the purification technique was investigated. The ζ potential was measured by electrophoresis method in the several pH conditions. When the ζ potential is low, the bubble locally unites and grows due to the coalescent phenomenon in bubbles. On the other hand, the coalescent bubble was not observed for the high ζ potential condition. As the result, the water purification technique by using micro bubbles is affected by the ζ potential.

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The effects of void fraction and surfactant for gas-liquid two-phase jets on cleaning with a venturi tube were investigated experimentally using two kinds of air-supply methods. The two-phase flows inside the tube and jet structures were observed with a high-speed video camera. The results show that the higher the void fraction becomes, the higher the cleaning efficiency becomes. Although the proportion of surfactant contributes the fission of bubbles involved in the jet, it has minor roles on the cleaning; the intermittent bursting of jets is a significant factor for cleaning. The observation shows that the backward air flow into the tube occurs near the outlet, which contributes to the occurence of the bursting. The cleaning efficiency with the naturally aspirated air supply is almost the same as that with the compressed air supply.

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The collapse and rebound of a spherical bubble filled with a noncondensable gas or condensable gas (vapor) were investigated by combining bubble dynamics and molecular gas dynamics. The polyatomic version of Gaussian-BGK Boltzmann equation was utilized for a gases vapor inside the bubble, while Fujikawa & Akamatsu's equation was utilized for the motion of the bubble. These equations were solved numerically with the kinetic boundary condition including a condensation coefficient that is an important parameter for phase change processes. The result shows that the condensation at a vapor-liquid interface of a vapor bubble is essential for the mechanism of collapse and rebound of the bubble.

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Dissolution process of micro-bubble plays an important role in the collapse. The contraction and dissolution processes of a spherical rising micro-bubble in water were investigated experimentally and numerically. We measured the bubble diameter and the velocity of a rising bubble using microscope that can follow the rising bubble in water. The experimental results show that the velocity of the rising bubble in water obeys nearly Stokes' law and hence the bubble behaves like a rigid particle in water. We also numerically calculated the time variation of bubble diameter by supposing a spherical bubble rising straight in water and using Rayleigh-Plesset equation and Sherwood number. It was found that the dissolution time of a bubble by the experiment is about 4 times slower than that by the calculation, and therefore the experimental results don't agree well with the numerical ones.

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By past researches in this laboratory, simultaneous measurements of drag, lift, side force and aerodynamic torque on highly spinning golf ball in wind tunnel flow became possible. In this reports, more accurate measurements of these aerodynamic forces are pursued to make well balanced and stable rotation golf ball, on which were set 3-barance weights on the equator line in every 120° of the ball. As a result, stable spinning of the ball and less scattered aerodynamic data are easily obtained, which compared with formerly carefully selected ball and conducted wind tunnel experiments in this laboratory. These results implied that even if delicate difference of the aerodynamic forces by the ones of dimple patterns on the golf balls enables to detect by wind tunnel tests.

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Less spinning soccer ball aerodynamics are studied by wind tunnel experiments. Aerodynamic forces of unsteady lift and side ones acting on the ball at rest are measured and estimated flight trajectory. Well agreements of flight shift magnitude in lateral direction between observed and calculated ones are obtained. As a result, in this stage the cause of this strange behavior of less spinning soccer ball is clarified by self-excited buffeting phenomenon of irregular behaviors of horseshoe-shaped vortex and longitudinal twin one, which already discovered with supper critical Re number region of smooth sphere by Taneda(1976).

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Style of ski jumping has been changed from a parallel one to a present V-style. Lift-drag ratio changes with the style of jumping. Flow field also changes with it. The difference of flow field was observed with smoke wind tunnel, cotton ball and tuft method. While strong but narrow band down wash was appeared in a wake of the parallel style, Wide band down but weaker wash was seen in that of V-style.

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In order to investigate the mechanism of propulsion in front crawl swimming, we measured flow around a disc-type wing. The structure of flow around the pitching and heaving wing is measured using particle image velocimetry (PIV) at Reynolds number of 1.25 × 10^4. The reduced frequency (K) is qualitatively shown to affect of the flow structure. At high reduced frequency (K=1.88), the leading edge vortex and tip vortex are formed in the wake of the wing and are shed when the circumferential velocity of wing reaches maximum. From two orthogonal views, it is possible that these vortexes are two section of a vortex ring. As a result we confirmed the earlier observation that high speed swimming cause sharp changes in direction with shedding of a ring vortex.

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Recently, much attention is paid to fin-swimming. Many researches have been conducted on the fin itself and swimming with fin, but many of them did not consider unsteady flow effect. Monofin moves intensively and hence the unsteady fluid force should be taken into account. The fluid force is closely related to the generation of vortices. It is widely known that the monofin itself has the thrust from the fluid by shedding vortices. However, the relation between the thrust and the generation of vortices has not been clarified in detail. In this study, we visualize the flow field around a monofin in pitching motion using the Particle Image Velocimetry (PIV) and also measure the thrust generated by the fin. We clarify the relation between the thrust and the generation of vortices in detail. When the propulsion is large, vortices of high intensity were generated in the wake of the monofin. It was found that the propulsion is larger for higher pitching frequency of mnofin and also the non-dimensional time at the peak of propulsion is delayed.

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A new method for measuring aerodynamic forces and moments is presented. In this method only a single image stream by a single video camera is required to measure forces and moments of a full 6 DOF motion of flying object. To minimize the error from the geometric distortion in images which is from the optical system, we applied the correction using the distortion model represented by polynomials of angles from the center of image. By estimating the distortion error in aerodynamic forces the importance of correction is found and the basic feasibility of the present method is suggested.

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The classical molecular dynamics was applied to a liquid molecular system confined by two solid layers controlled at different temperatures in order to investigate effects of structural clearances in nanometer scale to thermal resistance between a solid wall and a liquid molecular region. Clearance between surface structures on a solid layers, temperature gradients and molecular density in a liquid region were varied as calculation parameters in the present study. The calculation results showed that there was an optimal surface structural clearance in nanometer scale to reduce the thermal resistance at liquid-solid interface and that the optimal clearance corresponded to 6 - 10 times as large as the mean free path of fluid molecules.

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The dissociation phenomena of hydrogen molecule on platinum surface was analyzed by the Molecular Dynamics (MD) Method. The Embedded Atom Method (EAM) was used as the interaction between atoms in order to express the dependence of electron density on the interaction. The parameters were determined so that the results obtained by EAM method were consistent with that obained by Density Functional Theory (DFT). First the Potential Energy Surface (PES) obtained by the EAM were compared with that obtained by DFT to verify the validity of the potential. Next, the collision of a hydrogen molecule with a platinum surface was simulated by MD method and the dissociation probability was obtained.

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The Couette flow of a rarefied argon gas between two platinum walls is considered to investigate the characteristics of the reflected gas molecule at physically H_2O adsorbed surfaces. The analysis is based on the molecular dynamics (MD) method for the interaction of gas molecules with the adsorbed wall surfaces together with the direct simulation Monte-Carlo (DSMC) method for the motion of gas molecules. The tangential momentum accommodation coefficients are obtained at the wall whose temperature is 300K. The flow velocity between two walls and the distribution function of the reflected molecule are also obtained. It is found that the accommodation coefficient varies with the number of adsorbed molecules.

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The rotationally inelastic collision cross sections for the statistical inelastic cross section (SICS) model were estimated from the rotational collision number of experimental data and the rotational collision number calculated using the Wang-Chang-Uhlenbeck theory with the classical trajectory calculation (CTC). The SICS model with rotationally inelastic collision cross sections, presented in this study, were applied to the simulation of nitrogen normal shock wave structure and compared with experimental results. The density structures of SICS based on the rotational collision number of CTC and experiment in the shock wave were in reasonable agreement with those of experimental results. The structures of rotational temperature of SICS based on the rotational collision number of experiment were in good agreement with those of experimental results, however the structures of rotational temperature of SICS based on the rotational collision number of CTC in the highly non-equilibrium state were in poor agreement with those of experimental data.

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A new numerical scheme to solve the Boltzmann equation (the BGK equation) in phase space for the computations of rarefied gas is described on the basis of the Cubic Interpolated Propagation (CIP) method. The CIP procedure is extended to adaptive unstructured grid system by the Soroban grid. The grid points in velocity space can move dynamically following the spread of velocity space in a spatially localized manner. Such adaptively moving points in velocity space are similar to the particle codes but can provide higher-order-accurate solutions. Numerical solutions obtained by the Soroban-grid CIP are examined and the validity in various Knudsen numbers is proved.

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Recently, molecular gas film lubrication (MGL) has aroused the industrial interest. For example, flying head slider in hard disk drive (HDD) is suspended slightly above a rotating magnetic disk by molecular gas film. The flying head is lifted by molecular gas flow in the spacing. On the other hand, diamond-coated sliding surface is promising for gas bearing because it produces very low friction in the boundary lubrication. Nakamori et al. [Diamond Relat. Mater., 13 (2004) 2122] found experimentally that the friction between a diamond-coated surface and a metal surface was drastically reduced to zero as relative speed increased. But the mechanism of this phenomenon is still unsolved. In the present work, we investigate the floating mechanism by performing numerical simulations.

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For the development of high-vacuum technology and micro/nano-devices, interactions of gas molecules and solid surfaces must be analyzed. Molecular beams have been widely used for experiments of gas-surface interactions, but there are very few reports analyzing the internal energy (e.g. rotational energy) of diatomic or polyatomic molecular beams experimentally. Resonantly-enhanced multiphoton ionization (REMPI) method is a spectroscopic measurement technique, which is able to measure molecular internal energy. Moreover, REMPI has very high detection sensitivity, and it can be applied to analyses of very low density gas flows. In this study, we have tried to detect a nitrogen molecular beam by 2R+2 N_2-REMPI, and analyzed the rotational energy distribution of nitrogen molecules in the molecular beam.

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The object of this study is development of an ultra small shock tube for a high energy molecular beam source. First we evaluated a current loop valve for non diaphragm shock tube. As a result, we achieved the sufficient performance. Then we manufactured a shock tube using the current loop valve and evaluated it. The shock speed reached to mach number 5.1. From this mach number, we can estimate the translational energy becomes 1.1 eV. Finally, we evaluated the shock tube for molecular beam source by measuring the time-of-flight distribution. The translational energy of the shock-heated beam exceeded that of non heated molecular beam.

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We studied the interaction between He molecules and vertically aligned single wall carbon nanotubes (VA-SWNTs) using molecular beam scattering experiments. The time-of-fight (TOF) distributions of the scattered He molecules were measured at various angles of reflection. The angle-resolved flux distributions and energy accommodation coefficients were calculated from the TOF distributions. The angle-resolved flux distributions are all cosine distributions independent of the angles of incidence. The accommodation coefficients are very high and these are near the perfect accommodation. This is because He molecules go inside of the VA-SWNTs and collide with carbon nanotubes many times. The accommodation coefficients depend on angles of both incidence and reflection. This tendency suggests that VA-SWNTs have 'disturbed layer' at the surface.

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Pressure sensitive paints are widely used in many applications. The pressure distribution on surfaces obtained by the paint shows good agreement with that by other methods, like a pressure tap. Recently, the paint has been adopted to high Knudsen number flows, such as rarefied gas flows and micro/nano flows. The mechanism of the paint is based on the oxygen quenching of luminescent molecules in the paint. Usually the static pressure is inversely proportional to the luminescent intensity of the paint, because of the static gas condition. In high Knudesen number flows, it is not clear whether this relation holds or not. Here, in this study, we tried to relate the number flux of oxygen molecules and the pressures to the luminescence intensity, and clarify the limit of application in high Knudsen number flows.

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Generation and collapse of micro-bubbles were investigated by the results obtained by simplified experimental setup. The mechanism of bubbles generated by shear flow was first observed by a high-speed microscope. Collapse of a bubble is then studied based on the time variation of bubble diameter. The decay obeys a power rule whose power is 2/5. The rule expresses also a similarity solution. The gas pressure and its mass were also obtained as a function of time. The relation of the collapse time with the several bubble properties such as the initial diameter, temperature, Henry's constant and the diffusion coefficient is derived and the validity is discussed. It was found that the relation expresses the experimental evidence qualitatively.

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An optical fibre has interesting and useful characteristics, which are able to be applied to scientific measurement. Its Phase detection characteristic based on refraction difference between two phases was applied to bubbles/droplets measurement. Recently, demands for measurement of tiny bubbles/droplets increase in research fields of spray, automotive engine, fine chemistry, and so on. Meanwhile, laser science and engineering has made remarkable advances lately. Since femtosecond lasers spread in industry fields, their unique properties can be easily utilized for processing and measurement. In the present paper, a newly developed single-tip optical fiber probe processed using femtosecond laser is described, and its capability for simultaneous measurement of velocities and diameters of bubbles/droplets is discussed in consideration of surface tension and wettability of gas-liquid two-phase system.

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A laser trapping method was applied to trap microbubbles. An empty laser cone that was generated by focusing a laser ring was utilized in this method. Bubbles of the order of 10 micron in diameter were trapped and manipulated successfully using a dry objective lens with large working distance. The optical force acting on a bubble were also evaluated both experimentally and theoretically. It is shown that the axial force is about 90 pN when the net laser power is about 110 mW. The trajectory of a rising bubble was calculated by taking the optical force into account. The predicted trajectory was in good agreement with experimental data. Also, the growth or shrinkage of a laser-trapped microbubble was observed with a high-speed camera. The observation shows that two kinds of equilibrium radii exist for a shrinking microbubble. The first one is related to the equilibrium surface concentration of surfactant. The other is related to the decrease of the surface tension due to the compression of the surface area at the maximum surfactant concentration. The experimental results were compared with numerical solutions by taking the adsorption and desorption of surfactant and the dynamics surface tension. The simulations agreed with the experimental results.

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A variety of frictional drag reductions achieved by from microbubbles to large film-like bubbles are presented. The most curious fact found from their experiments is that the friction is so sensitively reduced by bubbles when the bubbles are smaller than the fundamental eddies in turbulence. This situation was, in the past, understood to be explained by homogenous model such as by Rheological expression because of less relative velocities between two phases. However the measurement results are unmatched with such a simplified theory. The discussion for the fluid dynamics mechanism is now advancing to extremely complicated model because of inevitable non-homogenous two-phase high-sheared turbulence. Despite to the knowledge accumulated to date, the key process hidden in the drag reduction still must be extracted to utilize the phenomenon as engineering technology that has already begun in maritime innovation. This report mentions how much the original bubbles have such potential to alter the boundary layer as well as the key phenomenon that triggers the effective drag reduction.

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From the first petrol vehicle on 1885, research of vehicle aerodynamics has been done. And currently, the importance of vehicle aerodynamics is getting up more and more. The flow phenomenon around the vehicle is related with fuel consumption, driving stability on high speed and driving comfort closely, so the development of vehicle aerodynamics should be done from the early stage carefully. In this paper, current situation of development of aerodynamics is explained with concrete example, mainly from the standpoint of experimental approach.

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[in Japanese]

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The world's largest class unsteady turbulence simulations of flow around vehicles were conducted using Large Eddy Simulation (LES) on the Earth Simulator in Japan. The main objective of our study is to investigate the validity of LES, as an alternative to a conventional wind tunnel measurement or the Reynolds Averaged Navier-Stokes method, for the assessment of vehicle aerodynamics, especially in the context of its possibility for capturing transient aerodynamic forces. As a result, we have demonstrated that LES using high performance computing technique will be a dominant method for improving the total vehicle aerodynamic performance.

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The steam turbines for ethylene plants are main model of our turbo machinery. In late years capacity tendency of ethylene plant to increase, and the steam turbine should be upsized in proportion to the plant capacity. This paper is introduced about the example of the high efficiency large size steam turbine for conventional ethylene plant, and high promotion of efficiency and reliability by our developed technologies corresponding to upsizing.

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