A joint research team of universities and private companies in Hokkaido, Japan has been organized to develop a small-scale reusable launch system based on CAMUI hybrid rocket. The main purpose is to drastically reduce the cost of rocket experiments and thus attract potential users such as metrological and microgravity researchers. The meteorological observation model of 400-kgf class motor is under development and a launch test in 10 km altitude is planned. Anomalous combustion occurred in the last four static firing tests out of seven serial tests with a flight model motor. This anomalous combustion is a specific phenomenon in the flight model engine and is not caused by the CAMUI method itself. Development testing to overcome this problem is under way and resumption of the launch program will follow.

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Simulating hurricane storm surge requires a highly accurate representation of the physical system with high resolution where geometry, topography or even frictional characteristics change rapidly in space. In addition, all processes must be considered including winds, atmospheric pressure, wind waves, riverine flows and tides. The actual physics of the storm surge development and propagation can then be well represented in the modeling system. The ADCIRC based SL 15b model is being applied by the U.S. Army Corps of Engineers to analyze past failures, to design new protection systems for Southern Louisiana and Mississippi and to evaluate flooding risk for the region in cooperation with the Federal Emergency Management Agency.

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I give a short introduction to the Bio-Nano Electronics Research Centre, Toyo University, and show some of the bio-nano fusion research, which has been carried out at the Centre since 2003. I also focus on the collaborative work with overseas institutions and researchers and the events such as international symposia and seminars.

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A film-type pressure sensor was developed based on the Fiber Bragg Grating (FBG) technology. FGB is commonly used in optical communications and is applied to stress/strain measurement recently. One of the merits of this sensor is the easiness to use, and time-varying pressures at multi-points can be measured. Wind tunnel tests were conducted and the pressures of 4 points on the wing model surface were measured. Obtained data were compared with the CFD simulation results and the results of another experiment, and the utility of the sensor was discussed.

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Development of a portable and easy use LDV system is attempted. In order to miniaturize the system, a small Nd:YVO_4 solid laser is adopted as the laser light source. Noise performance of the laser whether to be able for the LDV system was check by the light detector measurement and a high speed analog-digital converter. The laser has strong noise in the range of 100 kHz to 3 MHz appearing nonperiodically. To avoid this noise, the laser frequency is shifted by the Bragg Cell so that the Doppler frequency is out of the high noise region. A prototype of the LDV system with the Nd:YVO_4 laser was build as one package module. This systems was tested for velocity measurements in both the rotating solid disk and a laminar two-dimensional channel flow. The tests confirm that the LDV system works well for the mean velocity measurement. This result suggests the large possibility to develop the portable LDV system.

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A new type of velocimeter using a ronchi-ruling was developed and its performance was investigated. Stripes of laser light generated by a grid illuminated the tracer particles in fluid flow. When the particles pass through the strips, the burst signal of scattered right could be detected by a photomultiplier. Frequency of the burst signal was analyzed by a FFT analyser. From the spectrum of the bust signal, flow velocity was calculated for the pipe flow. Obtained profile agreed with the theoretical profile of the pipe flow. Moreover, applicability of the velocimeter on the unsteady flow was discussed. Wavelet analysis was used for the calculation of burst frequency of unsteady flow. By using this method, it was confirmed that the unsteady flow could be measured by this velocimeter.

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An imaging interferometer with low-numerical-aperture objectives and a CCD camera is proposed and studied for application to a particle image velocimetry (PIV) system. Sectional images are obtained based on the optical coherence tomography with the lateral resolution about 40μm. The motion of tracer particles within a coherence gate are detected from difference images between video frames and vector maps are obtained by using auto-correlation PIV. Two types of particle image acquisition conditions are found according to the fringe spacing, which affects the detected motion of tracer particles.

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The micro-PIV technique has been limited in two-dimensional velocity measurement. In order to measure instantaneous three-dimensional velocity distributions in a small space, three-dimensional micro-PIV technique have to be developed. In this paper, a new imaging method that could be conveniently applied to the three-dimensional measurement is discussed. The eccentric aperture method can measure three-dimensional position of particles using a one camera. By introducing a color separation technique to the existing method, the performance of the new method can be expanded twice, and it can process dense tracer pictures. The spatial resolution of the method is about 9.6 μm in z-direction. Some experimental examples are shown as well as the theoretical explanations.

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The micro-PIV technique has been limited in two-dimensional velocity measurement. In order to measure instantaneous three-dimensional velocity distributions in a small space, three-dimensional micro-PIV technique have to be developed. In this paper, a new imaging method that could be conveniently applied to the three-dimensional measurement is discussed. The eccentric aperture method can measure three-dimensional position of particles using a one camera. By introducing a color separation technique to the existing method, the performance of the new method can be expanded twice, and it can process dense tracer pictures. The spatial resolution of the method is about 9.6 μm in z-direction. Some experimental examples are shown as well as the theoretical explanations.

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An optical measurement technique to investigate the characteristics of spray in swirl nozzle flow was developed with PTV and digital holography method. The purpose of the present experiment is to verify the accuracy of measurement of droplet size, size distribution and velocity measurement. This technique aims to obtain these properties and velocity profile simultaneously with simple optical setup. The digital holography technique is two optical path observation with Gabor type optical system. In the present system, the two interference patterns and glare point images were recorded on a hologram. The hologram was reconstructed to obtained the focused image of the droplets, so the particle size was obtained from the reconstructed images and interference fringe analytically. These data was compared and the measurement error was estimated for silica particles as a calibration standard. The experimental results showed that the simultaneous measurement was possible in a good accuracy.

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A digital holography is a technique that obtains the reconstruction image by recording of the holograms with the image sensor such as CCD electrically, and processing the holograms with the computer. A high-speed measurement became possible because it was able to do all processing digitally compared with the holography that used a past photographic plate. However, the improvement of the spatial resolution becomes a problem by the problem of the low resolutions of the image sensor compared with the photographic plate. In this report, it has aimed to attempt the improvement of the spatial resolution by using the phase and amplitude information on the wave field recorded as digital data.

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This paper presents a technique for the measurement of size and position for the particles distributed in three-dimensional space, based on digital holography. In this technique, the phase distribution relative to background phase is computed in the measuring volume behind an observed digital hologram to detect the position and diameter of each small particle. The present technique is robust to the holograms with higher number density of particles as compared with a conventional technique using the information of reconstructed light intensity. The measurement accuracy of the present method is evaluated in numerical simulations and the influence of some measuring parameters on it is shown for artificial particle models.

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In this study, a digital holographic technique has been developed for measuring 3D unsteady velocity distribution from a time series digital hologram, and the performance is examined by numerical simulation and experiment with a high speed camera. For the method using the phase that is relative to that on the background, the measurement accuracy has been improved as compared with our previous method using light intensity information. In numerical simulation, it is shown that RMS error in depth is 65μm for particle size 25μm. If this technique is applied to the measurement of the bubbly flow in 3D space, 3D velocity vectors are going to be successfully obtained to confirm the feasibility of this technique in real flow measurements.

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In this study, a digital holographic technique has been developed for measuring 3D unsteady velocity distribution from a time series digital hologram, and the performance is examined by numerical simulation and experiment with a high speed camera. For the method using the phase that is relative to that on the background, the measurement accuracy has been improved as compared with our previous method using light intensity information. In numerical simulation, it is shown that RMS error in depth is 65μm for particle size 25μm. If this technique is applied to the measurement of the bubbly flow in 3D space, 3D velocity vectors are going to be successfully obtained to confirm the feasibility of this technique in real flow measurements.

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A multi-functional minute ER device of liquid crystal has been developed and examined. Divided electrodes were utilized in order to control total ER effect of the device. Moreover, the flow rate of the liquid crystal in the device was estimated from optical signal obtained with polarizing LED light and a photo-IC attached to the ER device. The flow rate estimation method developed here was useful in low shear rate region. Apparent ER effect of the device was easily controlled changing the area of the electric field applied. Then, we had developed a total control system using the flow rate estimation and ER effect control mentioned above, and the flow rate was automatically controlled with good accuracy.

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The ER suspension behaves like a Bingham fluid having yield stress, which can be rapidly changed in a reversible manner by applying electric field. The advantages are a simple and compact construction, and the response time of several m sec order. In this research, at first, the pressure response and flow behavior of ER suspension across a micro gap channel of ER valve have been investigated. Based on the results, three ports micro-bellows-actuator driven by a pair of micro ER valve has been designed and fabricated by photolithography for the use of controlling one unit of tactile-pin for Braille display system. The relationship between the ER fluid supply pressure and the actuator force is discussed to determine enough force to push up the Braille tactile-pin.

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The electrorheological fluid (ERF) is a fluid which show the non-Newtonian fluid characteristics when the electric field is applied. Owning to the electrorheological effect, ERF has been regarded as promising substance for engineering applications. In this study, a basic experiment of the gap flow in a closed piston - cylinder system of ER fluid was carried out with regard to an engineering application to dampers. The purpose of this study is to elucidate flow behaviors of ER fluid in the piston - cylinder system by experiment and visualization. From the results, it is confirmed that it is possible to control a damping effect by a change of an electric field. Also, it was observed that flow field in a cylinder is largely affected by a variation of a piston velocity.

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If we can control the actuator by light, wide application of that is considered in optical micro-machine. Fluidic device controlled by light have investigated by many investigators. However these devices are driven by means of heat generated by light. In this experiment preceding investigations are carried out to apply radiation pressure of light as inputs to the fluidic actuator. So we select very small fluctuating pressure as input for the fluidic actuator and basic investigations are performed by laser beam radiation pressure.

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The integrated model of thermofluid, splat formation and coating formation for the cold spray process has been established. In-flight behavior of nano-micro particles and the interaction between shockwave and particles in supersonic jet flow impinging onto the substrate and further effect of electrostatic force on the particle acceleration are clarified in detail by carrying out a real-time computational simulation. The optimal particle diameter for impinging particle velocity exists and the maximum impact velocity of 732 m/s is obtained for the particle diameter of 1.3μm. Particles with the diameter of submicron interacts with shockwave and particles are decelerated prior to the impact. However, the particle can be accelerated considerably by utilizing electrostatic force even in the presence of shockwave. Finally, based on the integrated model, coating thickness in an electrostatic assisted cold spray process is successfully evaluated.

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The thermofluid characteristics, input power and various kinds of radical productions of the air plasma flow are clarified experimentally. Moreover, the heat vortex behavior generated by the pulsed arc discharge in the torch is clarified numerically by introducing the real operating conditions. The production and recombination processes of the some kinds of the radicals in the air plasma flow are clarified numerically under the applied high electrical field.

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A numerical method for simulating supercritical fluids of arbitrary substance is presented. The preconditioning method developed by the authors is coupled with the PROPATH, which is a database for thermo-physical properties developed by Kyushu University. The present method enables us to calculate an arbitrary substance at arbitrary pressure and temperature conditions, such as CO_2, H_2O, N_2, and CH_4 programmed in the PROPATH, accurately. Therefore, the present method can apply to simulate a number of practical problems for supercritical fluids especially in near-critical conditions. As numerical examples, Rayleigh-Benard convections assuming a near-critical fluid of CO_2, H_2O, and N_2 are calculated and the calculated results are compared with each other and the calculated results assuming an ideal gas.

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This paper presents the capability of the supercritical-fluids simulator developed by us to simulate flows at atmospheric conditions. This simulator uses a numerical method based on the preconditioning method coupled with the PROPATH database. Supercritical fluids of arbitrary substance can be calculated using the simulator. Also flows of arbitrary gas and liquid such as water vapor and water liquid can be simulated considering their compressibility. As numerical examples, carbon-dioxide, water, and nitrogen in a square cavity at several pressure and temperature conditions are calculated using the simulator and the calculated results are compared with each other.

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Magnetorheological suspensions (MRS) behave like a Bingham fluid having yield stress which can be rapidly changed in a reversible manner by applying magnetic field, and are anticipated some applications of industrial devices such as damper, a valve, a clutch, a brake, and so on. In these applications, one of serious problems is the sedimentation of dispersed particles in the MR suspension in an off-working state. In this research, for the purpose of preventing the particles from settling, an MR composite made of the sponge containing the MR suspension has been developed and the dynamic nonlinear viscoelastic properties of the MR composite in oscillatory shear mode under magnetic flux normal to the shear direction have been investigated by using a newly developed oscillatory shear type rheometer.

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In this research, an MR brake using magneto-rheological (MR) fluid has been developed to be applied to an induction motor as a high-performance braking device, instead of conventional electromagnetic mechanical brakes. The conventional brakes have some problems such as the fall of braking performance and the generation of acoustic noise in long time use. These problems will be resolved by using the MR brake. There are two types of motor brakes. Excitation-operation type MR brake has the advantage that the braking torque can be changed in proportional to the applied electric current, but the electric power consumption for holding the motor for a long time increases. Therefore, non-excitation-operation type MR brake that has a holding function in the state of non-excitation has been developed in this study. The characteristics of the generated torque, temperature, and braking performances of the developed non-excitation-operation type brake utilizing MR fluid have been investigated to examine the feasibility to apply it as an induction motor braking device.

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Experimental analysis on the cluster formation of MR fluid and rheological properties under the magnetic field are carried out. Through the measurement of ultrasonic propagation velocity in MR fluid, the cluster behavior in pressure-driven flow is clarified in detail. Finally, the flow control characteristics of MR fluid in a rectangular channel are evaluated to provide the fundamental data for the design of the advanced MR valve system.

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Magnetic fluid's behavior under progressive magnetic field is investigated numerically. Numerical simulations are performed using the ALE type of the GSMAC finite element method. The velocity profiles and pressure distributions of magnetic fluid are shown. The magnetic fluid may not always flow through the progress direction of magnetic field. The fluid is transported with motion of coming and going to the progress direction of magnetic field. The effects of the depth of magnetic fluid layer and frequencies of the progressive magnetic field on the surface velocity are examined.

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