The present paper describes a fundamental uncertainty analysis for a flowrate measurement in a pipe using an ultrasonic Doppler velocity profile method and an evaluation of the estimated uncertainty by an actual flow calibration. The uncertainties are estimated for internal factors originating from the measurement equipment; UVP provided by Met-Flow sa. and external factors depending on on-site measurements, such as the inclination angle of the ultrasonic transducer. The relative expanded uncertainty due to internal factors is estimated to be 0.34% with a coverage factor of 2. The relative external uncertainty including external factors is estimated to be from 0.42% to 2.13% depends on the inclination angle of the transducer. The results of the actual flow calibration under the same condition as the uncertainty analysis are within the range of uncertainty considering the internal factors.

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The air-coupled ultrasonic velocity profiler for steam flow measurement is developed. A new ultrasonic sensor for air-coupled ultrasonic measurement was manufactured and measurement system was developed for steam flow measurement. The air-coupled ultrasonic sensor has a matching layer to reduce the acoustic reflection between sensor and the air. In order to amplify detected signal, an external amplifier is developed, which can amplify the detected signal without noise from pulser/receiver and environment. Steam jet flow is measured to demonstrate the developed system, and the possibility of the steam flow measurement by air-coupled ultrasound is revealed.

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Ultrasonic pulsed Doppler method (UDM) can obtain velocity profile on the ultrasonic beam path. By integrating the velocity profile over the pipe, flow-rate can be derived with high accuracy. In order to measure higher velocity by using feedback method, the larger measurement volume is required. With increasing of the measurement volume, it has been reported that the measurement accuracy near-wall region becomes low. In order to improve the measurement accuracy, multi-wave ultrasonic method which employs two ultrasonic sensors with basic frequency of 2 & 8 MHz is proposed. The velocity distribution was accurately obtained over the pipe by combining velocity distributions at 8 MHz for the near-wall region and 2 MHz for the region far from the transducer. Furthermore, the accuracy of the flow-rate was also improved with the proposed method.

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A new velocity profile measurement system with ultrasonic phased array technology was developed for flow visualization. Multiple transducers are arranged in a variety of positions to obtain a flow map using the usual ultrasonic velocity profiler, and it causes the measurement system larger. Therefore, anew measurement system employs velocity vector reconstruction method by using only one array sensor and ultrasonic phased array technology. The hardware and software was developed, which is applied phased array technology and can obtain the velocity vector profiles. Two dimensional flow mapping of a Taylor-Couette flow was conducted by the developed system, and the availability of the system was confirmed.

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Taylor vortex flow with a small aspect ratio has characteristics such as the different vortex structure, because of the Ekman effect in the top and bottom boundary layers and the acceleration of the inner cylinder. This feature is expected to develop a new typed mixing bioreactor system, but this vortex flow mechanism like a chaotic flow has not been investigated much. Furthermore, the multiphase flow such as the solid-liquid flow is important to be analyzed with a measurement system. An ultrasound measurement method is a useful device for observation of the flows. In this report we mainly analyzed the vortex structure in higher Reynolds number with using the ultrasound measurement system, and compare the result with Direct Numerical Simulation.

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This paper evaluates the performance of a digital holographic particle measurement using deconvolution for measuring a three-dimensional flow. In digital holography, the measurement accuracy in depth is reduced because a reconstructed particle image is elongated along depth direction. In order to overcome this difficulty, a deconvolution technique is employed the suppressing the particle image elongation. We apply this digital holographic particle measurement using deconvolution for the detection of particle displacement. In numerical simulation, the measurement accuracies with and without deconvolution technique are evaluated for the model of cubic cavity flow. It is shown that the measurement accuracy is improved by the present method with deconvolution technique.

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By using the phenomena that the concentration of particles decreased by passing through branch pipes, a rotating filter was developed to remove particles in two phase fluid. It was found that the concentration in branch pipe decreased furthermore by adding a wall right in front of its entrance. We confirmed that it could be applied to rotating filter to remove more aluminum powder in water.

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Behavior of an air flow around permeable porous plate placed perpendicularly on a ground plane was experimentally investigated with the aid of a laser Doppler velocimetry. The experiment was performed for three types of porous metal plates with different porosity and permeability. Prom profiles of mean streamwise velocity behind porous plate, we found that a recirculation region reduced with increasing permeability and disappeared for the highest permeability. These velocity profiles were compared to the theoretical analysis from Gortler, and agreed with the solution for values of σ = 10 except for just behind the porous plate with highest permeability. The behavior of velocity field suggested that the permeable porous plate with highest permeability led to stable windbreak effect.

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The micromixer, which has a rotor with a curved channel, is studied experimentally. The Taylor-Dean flow in a curved channel of rectangular cross-section is investigated using PIV (Particle Image Velocimetry) and LIF (Laser Induced Fluorescence) methods. Two walls of the channel (the inner and top walls) rotate around the center of curvature and a pressure gradient is imposed in the direction of the exit of the channel. The non-dimensional parameters concerned are the Dean number De and the Taylor number Tr. Photographs of the flow in a cross-section at 180° downstream from the curved channel entrance are taken by changing the flux (De) at a constant rotational speed (Tr) of the channel walls. It is found that good mixing performance is obtained in the case of De ≤ 0.1Tr. This tendency appears more strongly if aspect ratio is large. And we have confirmed the effect of aspect ratio on the mixing process.

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We study the infiltration flow in a soil-model. Our question is how the flow decides the direction under the soil. The soil model consists of glass beads between two thin glass plates. We use 2.0mm diameters of glass beads whose diameters is similar to real sand constituting a granule. The meandering is typical flow pattern of the infiltration. The precursor of the flow direction is observed of the front edges of the flow by using the image processing. It is a thin film on the plates. The influence of single bead for meandering flow is studied. The angle between the center of bead and the front edge of droplet is measured when the droplet puts on a bead gently. The angle changed with the diameter of bead.

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Recently, it is important the keeping high thermal efficiency of the development of the new type of heat exchanger when it's surface was deposited impurities. Numerical simulation of the particle behavior that likened impurities to sand and snow is developed. Specifically, the Lagrangean approach is employed the particle behavior in the complicated flow field by solving the equation of motion with gravity and drag. As for this calculation, the particle comes under an influence of the flow field to change every time, but is a calculation of one-way where influence does not give it to from the behavior of the particle in the field.

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We want to put into a diffusion flame jetted Acetone micro droplets of diameter 30μm in our study. Generation of luminous flame was observed in the case of narrowing the distance between the micro droplets at this time. We were measuring the concentration in the micro droplets around by focusing on LIF method to elucidate this cause.

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This paper presents an iterative method for accurate particle detection in digital holographic measurement, and the performance evaluation is numerically carried out for particle depth measurement. Digital holography is a powerful and monocular technique for three-dimensional measurement to be applied to quantitative measurements of small objects, such as fuel spray and cluster of bubbles, in the industrial field of fluid engineering. In the present iterative method, virtual particles are introduced to be numerically placed at the first estimate of the particle positions in order to overcome conventional problems in which measured depth position has non-negligible error and particle detection itself is done by mistake. Then, virtual particles are adjusted in such a way that observed hologram patterns match those computed for virtual particles to improve measurement accuracy by regarding the converged solution as final measurement results. In numerical simulation, the effect of particle parameters on depth measurement accuracy is investigated by using multi-particle models for particle size 10〜50μm.

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Chaotic mixing in a curved-rectangular channel flow is studied experimentally and numerically. Two walls of the channel (inner and top walls) rotate around the center of curvature and a pressure gradient is imposed in the direction toward the exit of the channel. This flow is a kind of Taylor-Dean flow. There are two parameters dominating the flow, the Dean number De (∝ the pressure gradient) and the Taylor number Tr (∝ the angular velocity of the wall rotation). In the present paper, we analyze the physical mechanism of chaotic mixing in the Taylor-Dean flow by comparing experimental and numerical results. It is found that good mixing performance is obtained in the case of De ≤ 0.1Tr. This tendency appears more strongly if large aspect ratio and Condition I.

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We often perceive odors of smoking at seats for non-smokers of cafes and restaurants. A new ventilation system was developed by using the knowledge that neither flow separation nor backward flow could occur in case of increasing velocity distribution near walls by using 1/10 models. In this paper, the effects of the system was examined by using an actual scale model, and it was confirmed that the system could remove smoke promptly, and that unsteady flow prevented smoke from staying in the backflow behind columns.

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Identification method of flow pattern was studied by using sound data which were taken and analyzed to flow through pipe. Sound data of two-phase flow were taken on flow through vertical pipe. Five kinds of flow pattern were made for sound data and analyzed. Frequency spectrums could show the features in each flow, almost these features existed below 250Hz. By using auditory roughness which is one of the methods of psychoacoustic sound quality evaluation, we found specific feature on containing large amount gas flow.

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Recently, shower of bath is required water saving. In conventional shower, comfortable is proportional to flow late. We have studied two phase ejector for shower that draws air into the shower. The shower is comfortable and water saving compatible. We have developed a new fluid device in two phase ejector for more comfortable shower. This device uses a deference of pressure between in vortex chamber and by driving flow. The driving flow and suction air is oscillatory by different pressure, and shower water discharge has intermittence. As a result, new shower is more comfortable than previous shower by feeling of stimulation.

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When a cylinder rotating around horizontal axis was put on the turntable rotating around vertical axis, liquids of high viscosity in the cylinder were stirred well with the effects of Coriolis force. In this paper, we tried to stir powder and powder with Coriolis force. When a device to trim the powder attached to the cylinder wall was added, it was found possible to stir powder and powder with Coriolis force. A computer program was developed to catch the positions of particle from a photograph of powder and small particles, for example, mixture of wheat flour and aluminum powder. And a method to evaluate the uniformity of mixture was established. Then the better conditions to stir powder and powder were studied. As a result, they were stirred well when a ratio of the rotation number of cylinder and that of turntable was a certain value.

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It is important to separate and collect particles from solid-liquid mixture in order to reduce in environmental load and treatment cost of waste fluid. In this study, we try to separate and collect particles from the mixture by ultrasonic waves with relatively low frequency. In present report, we use garnet as removal particles. The particles are fully stirred in test water and then ultrasonic waves are irradiated with some frequencies. The particles behavior observed by a high-speed video camera is analyzed by a time series image analysis and correlated with sound pressure distribution.

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Solution growth is used for light emitting devices. The equilibrium between the solid and liquid phases becomes an advantage and also a disadvantage. In the mass-production, the crystals have good quality and this technique will be eco-friendly. Recently, introducing fluid flows in liquid solution begins to overcome that disadvantage. As a preparation to treat the flows, we consider cases without the flows because we know an analytic solution for an ideal case as shown in 2014 JSME annual meeting. In real apparatuses, the size of liquid solution is finite. Finally, the boundary layers of mole fractions for the solutes reach the end of liquid solution. We estimate the error in applying it to the finite case, using a unique method with mass conservation. The tolerances of gradients for the mole fractions on the growth interface are guaranteed within a growth time. This method will be applicable for other transport phenomena.

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We have developed a new soundproof system which is installed additionally on existing railway concrete viaducts. This system is effective in decreasing the noise caused by the running of a train and can reduce wind load transmitted to the viaduct because of a movable soundproof plate of the system under a strong wind condition. In this system, the soundproof plate is supported on rotating shafts on the both sides of the plate. It is effective to set the axis position near the center of the plate in height direction so that the plate can return to the original position soon after the wind weakens. In this study, the influence of the axis position was investigated in a wind tunnel test. Furthermore, the drag coefficient applied to the model was determined experimentally.

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In order to develop a flight control technique of a hovering type flying object with three rotors, simulations were conducted by means of the Verlet algorithm, which enables us to analyze the behavior of the flying object under a variety of conditions. Specifically, we here discuss how the shape and weight of the flying object affect the stability of the hovering flight, and also the possibility of attitude control in terms of the angle of the slope of the flying object, the angular velocity and the angular acceleration. As a result, for the case of the present unstable flying structure where the recovering force does not significantly function, the inclination angle and the angular velocity of the flying object are not sufficient for controlling the attitude, and therefore the incorporation of the angular acceleration is indispensable to successfully controlling the flying object in the stable situation of the hovering mode.

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Computing flows around an object with large deformation is important and interesting. In this study, to calculate such flows in a short time without crushing computational elements, we proposed new approach called 'biaxial sliding mesh approach', which has multi sliding planes. Furthermore, this approach was applied to flows around the tilt rotor aircraft which has advantages of both of a helicopter and a fixed wing aircraft by tilt rotors. After checking the approach on simple test problems, a flight what it takes off and changes from helicopter mode to airplane mode was simulated.

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In running Aero-Train, it doesn't have enough levitation stability. This study is intended to clarify the aerodynamic properties with control surface to enhance stability. When the flap angle is in the range from -10 to 10 degrees, lift coefficient is sensitive to the angle of control surface. Drag coefficient has a minimum value when the angle of control surface -10 degrees, and the gradient of the drag coefficient change at the same angle. Moment coefficient become 0 around the angle of -10 degrees. Lift-drag ratio is almost constant when the flap angle is in the range from 0 to 10 degrees.

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We investigated the aerodynamic characteristics of the concentrated photovoltaic system (CPV) of two-divided-panel type. Since the acceptance side of the conventional type of CPVs always faces upside in the night, the accumulated sands or dusts on it impede power generation. For the CPV of two-divided-panel type, the panels can be rotated upside down, and it is easy to clean up the acceptance side. Attention was focused on the effects of the slit between the two panel. It was found that for symmetric attitudes with no yaw angle and small angles of incidence, there exists bi-stable mode in the moment around the shaft.

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There have been about thirty wind-induced accidents of train have been occurred in Japan since railways were opened. To investigate aerodynamic characteristics of a train under a natural wind, a full-scale model test was performed, and wind velocities and aerodynamic forces on the vehicle models were measured. The values of aerodynamic coefficients calculated from these data were scattered widely but, the causes of scattering have not been clear. In this study, we discussed the influence of wind fluctuation on the scattering of side force coefficients. Both wind fluctuation and side force fluctuation are modeled using a statistical model, and then side force coefficient is evaluated by these fluctuation models. Comparing with experimental results, we found that side force coefficients from these models are in good agreement with experimental ones.

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Many experiments were done to study hydrofoil's characteristics near the free surface. But, Reynolds number has been transition zone in examination cases of hydrofoil. Reynolds number and turbulence effect are important for foil characteristics. For the reason, a NACA4412 hydrofoil section was computed by CFD to research effect of Reynolds number near the free surface. Used CFD solver is SURF developed by NMRI. First, computational and experimental results were compared to discuss turbulence effect in experimental cases. After that, Computational results were compared with other Reynolds number (A) to discuss turbulence effect in turbulent flow range.

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The practical use of the exhaust heat has a great potential in saving energy. Uprating the absorption refrigerator is one of the options. For the optimum equipment design, two or three-dimensional thermometry is important. Laser induced fluorescence (LIF) is often used to measure the temperature of water. In the absorber of absorption refrigerator, the water amount varies momently. The change of dye concentration affects the LIF signal, therefore, there are few techniques to measure temperature applicable to absorption refrigerator. In this study, authors propose a new technique that combines the LIF and particle tracking velocimetry (PTV). We developed a new hollow microcapsule tracer by doping temperature sensitive fluorescent dye. This method does not need to dissolve the fluorescent dye to the working fluid and quantitative measurement would be possible regardless of the change of concentration. Results showed that the functional particles of this study have a high sensitivity.

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In order to investigate the characteristics of intense radiation around Si-based heat-resistant materials in air plasma freejets, radiation measurements were performed around ablating silicon carbide test piece in the air plasma freejets. In previous study, by using a spectrometer, characteristic continuum radiation, atomic Si lines, OH molecular bands, and CN molecular bands were observed in common. In this study, radiation measurements were spatially conducted with two kinds of band-pass filters corresponding to 520 and 650nm in wavelength and video cameras. It was found that the relative intensity distributions were different with each other, the intensity distribution corresponding to 650nm was higher than that to 520nm, and estimated temperature around ablating the test piece was about 2,600K at 7.0mm position from nozzle exit on flow axis.

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To use liquid fuel efficiently, atomization is important. Atomization consists of many small droplet so we have to measure temperature and density with appropriate spatial resolution to understand combustion and evaporation. In this research, we tried to measure temperature distribution around flat heating wire with Mach Zehnder Interferometer and investigate temperature and spatial resolution.

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Pressure sensitive paint (PSP) is a useful noncontact measurement technique to obtain continuous pressure distribution on solid surfaces. The application of PSP to low speed flows in mechanical engineering fields, including unsteady flow measurement related to analysis of aerodynamic noise, is highly demanded. Polymer-based PSP has high pressure sensitivity for low-speed flow field, but the unsteady response of the polymer-based PSP is not examined enough. In this study, we investigate the unsteady response of the polymer-based PSP, to evaluate the feasibility of the polymer-based PSP as a measurement tool for unsteady low-speed flows. We have applied the polymer-based PSP in low-speed flow to measurement of unsteady pressure distribution around a circular cylinder, and compared the amplitude spectra of PSP and that of pressure probe, which are obtained by FFT analysis. Furthermore we have visualized the distribution of the integrated intensity of the PSP amplitude spectrum around the peak, to visualize the area with large pressure fluctuation on the cylinder.

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We carried out the EFD/CFD study on characteristics of critical nozzle flow meter. The test conditions are from 1.6×10^4 to 1.2×10^5 at Reynolds number. The evaluated characteristics are the discharge coefficient of the critical nozzles. The significant differences were not able to confirm between EFD and CFD. These results show that CFD can reproduce the EFD results well.

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The present study discusses thermal nano-scale flows by the lattice Boltzmann method(LBM). Although recent LBMs discuss nano-flows, reports on nano-thermal flows are rare. Our group showed that the regularization procedure was needed for complex nano-scale flows. However our preliminary study also showed that the common thermal model did not capture thermal jumps on a wall when the regularization was coupled with. In this study, the model is improved to capture thermal jumps with the regularization. To verify the present model, Fourie, Poiseuille and square cylinder flows are simulated. It is confirmed that the results of the present model correspond well with the reference data.

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We verify the effectiveness of the two-relaxation-time (TRT) collision operator in reducing boundary slip computed by the immersed boundary-lattice Boltzmann method (IB-LBM). Rigorous analysis of the symmetric Poiseuille flows reveals that the relaxation time for the antisymmetric part controls the boundary velocity and the boundary slip velocity computed by the IB-LBM. In the simulation of the cylindrical Couette flows, the boundary slip caused by the use of the single relaxation time (SRT) model in the IB-LBM impairs the accuracy that the LBM intrinsically possesses. The IB-LBMs with the TRT exhibit second-order accuracy in space for both the direct forcing method and the implicit correction method.

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This research discusses flows inside a carbon nano tube(CNT) by molecular dynamics simulation. For the fluid molecules, oxygen molecules and virtual monoatomic molecules whose size and weight are similar to those of O_2 are considered. When the diameter of the CNT is very narrow, the flow rate of the oxygen flow becomes larger than that of the virtual monoatomic molecules, though generally the flow rate of the oxygen molecules is similar to that of the virtual monoatomic molecules. From this result, when the diameter of the CNT is very narrow, it is found that the effects of rotation and difference of the molecular structure cause the different flow characteristics.

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Capillary gravity waves excited by an obstacle are investigated numerically. Navier-Stokes (or Euler) equations are solved under the resonant condition for which the large-amplitude solitary waves are generated. It is found that the large-amplitude nonlinear waves often generate short waves both in the upstream and downstream of the obstacle under the action of capillary effects. These short waves interact with another nonlinear wave in a long time. Comparison of the results with the weakly nonlinear theories reveals that the theories are applicable to the cases with strong capillary effects.

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The interactions between bubbles and ultrasound in a blood vessel are investigated numerically by using the boundary element method (BEM). The blood vessel is modeled by an elastic tube with spring-mass system. The dynamics of two bubbles in the tube are simulated successfully by considering the three-dimensional deformations of the bubbles. It is shown that when one bubble is initially located on the axis of the tube and the other is not on the axis, the translation toward the side wall of the tube causes the inclined liquid jet formation on the bubble surfaces. A heavier mass of the side wall leads to a longer period of bubble oscillations because the natural frequency decreases with increase in the mass. A simple bubble model for investing bubble oscillations in the tube is also introduced and is combined with the spring-mass system of the tube: the bubble is represented by the point source for the bubble volume oscillation and the dipole for the translational motion. The result using the bubble model is in good agreement with that obtained from the fully three-dimensional BEM calculation.

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Three-dimensional numerical simulation is carried out to investigate the onset of turbulence in a bypass transition. Short duration jet is ejected into a low-speed streak and their growth is simulated. As a result, it is shown that the onset of turbulence appears as a when the number of strong vortices start to increase, which is a little later than when the effective vortex stretching starts to increase.

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In this study, the direct numerical simulation for homogeneous shear turbulence in the system rotating along the streamwise direction with three shear rates is performed. Owing to the rotation effect, the turbulence energy becomes small during the initial short time, and the anisotropy of the Reynolds normal stresses and that of the kinetic power spectra are strengthened. In the case of the strong shear rate, the small vortex structures are activated and stand in a line along the rotating axis.

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The aim of this investigation is to develop an open type cross-flow runner for eco-friendly pico-hydraulic turbine utilizing an extra-low head waterfall. We use a flow direction control method with a convex shaped channel to adjust precisely the position of the runner every time when flow rate changes. But this method has disadvantage that water surface deforms and fluctuates. These water fluctuation disturbs high performance. So, we investigated experimentally the characteristics of water flowing over convex surface. As a result, there are three patterns in the growing rate of waving defer motion of the water.

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Numerical simulations are carried out to find out the optimum operating mode of a piezo-ceramic actuator attached to a flat-plate surface. The goal is to generate a strong velocity fluctuation waves in a boundary layer. As a result, it is shown that strong waves can be generated when the actuator is operated concentrating the production of vorticity fluctuations to smaller region. It is also shown that making the actuators to travel downstream at the speed of the target T-S waves can generate even stronger waves.

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Large-eddy simulation of flow around a train was conducted to investigate unsteady under body flows. The results of this study showed that large lateral velocity fluctuations were generated by two vortex streets along the train and that they propagated along the streamwise direction under the train.

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It is supposed that the pressure drop might become large when the heat exchanger headers are designed small in order to make the heat exchanger compact. This study discusses the test results on the pressure loss in the sudden contraction and expansion of the air and the water flow, when their elbow angles show 45 and 90 degrees in the rectangular pipe. This study also reports the new correlations among the concerning elements in the pressure drop coefficient.

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An experimental study is carried out for dividing flow through 90° T-junction of square cross-section. The Reynolds number based on the mean velocity at the main channel and the hydraulic diameter ranges from 1.3×10^3 to 2.0×10^4. The flow rate ratio (ratios between the flow rates in branch and main channel) is set at 0.2, 0.4, 0.6 and 0.8. The loss coefficient and wall static pressure are measured to quantify the energy loss. The velocity profiles are measured by a PIV system. At laminar flow, the loss coefficient of branch channel increases rapidly with increasing the flow rate ratio. This is because the reverse flow from the main channel flows into the branch channel. In turbulent flow, the recirculation region of the main channel becomes narrow as compared with laminar flow.

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In this study, a flow meter using multipath ultrasonic shift is proposed for the internal airflow. The experiment was conducted between 2.0m/s and 9.0m/s using a pipe with diameter of 160 mm. The frequency of ultrasonic was 40kHz and ultrasonic was sent as burst signal of 20 cycles at interval of 50ms by function generator. Flow rate was calculated as the average of each measurement path. The resultant error of straight pipe and 2 types bended pipe measurement were lower than 4%, 16% and 25% respectively against reference flow rate measured by orifis flow meter.

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The phenomena with relation to fluid mechanics are often taken up in scientific books for popular readers. However, the explanations on principle of them have been described under misunderstood knowledge on fluid mechanics in many books. It was said for a long time that siphons worked by the atmospheric pressure over an upper surface. But this model is wrong as many persons state. Also there are many ideas on the principle of a siphon. We discuss about the reason in this report.

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Nasal continuous positive airway pressure (Nasal-CPAP) is frequently used in the care for the preterm neonates to recruit its sustain and maintain the lung volume. The authors have developed Nasal-CPAP device with a bypath (B-NCPAP) of horizontal mounting type which reduces the breathing work for the neonates. In the last report, we have obtained device properties of B-NCPAP with prong for the several diameters. As the results, it was shown that pressure decreased at the expiration. In this report, we added HFO function to the calculation model of the B-CPAP device and report the numerical result, when CPAP pressure amplitude reduce during respiration phase.

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In this study, we have investigated the fluidity responses after flow reversal of carbon nanotube (CNT) suspensions with Newtonian carrier liquids in stress-sweep tests. The suspensions have showed transient decrease in viscosity, i.e., increase in fluidity, after flow reversal in shearing direction. Moreover, precipitous recoveries in viscosity were appeared at a certain shear rate. In order to quantitatively clarify the viscosity recovery, a typical strain γ_p corresponding to the peak of viscosity recovery was estimated. Dependence on viscosity of the carrier liquid was mainly examined and it is clarified that there is almost no influence of the viscosity on γ_p in the cases with higher viscosity of the carriers. But the smaller transient response and lower γ_p was obtained with light carrier liquids.

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A technique to evaluate the orientation of director of liquid crystal on the surface of thin liquid film is developed in order to examine its drying process. The drying process is quick and then the high-speed data acquisition is required. We apply the reflection polarimetry technique with the high-speed polarization state modulator. The modulated laser beam is irradiated on the surface at a certain incident angle, and the light intensity of the reflection beam is measured. The transient behaviors of the reflection rate of the S and P polarized light are evaluated simultaneously. A dried chromatic dye thin film is used as a test surface and the orientation angle is detected by the difference of the reflection rate. The change of the optical anisotropy in the drying process of a polymer liquid crystal of HPC is also evaluated using this technique.

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The motion of a sphere sedimenting through a viscoelastic worm-like micelle solution (cetyltrimethylammonium bromide and sodium salicylate in deionized water) in a square duct is experimentally investigated using a PIV (Particle Image Velocimetry). Abrupt changes in sedimenting velocity of a sphere are attributed to the onsets of strong downward flow behind a sphere which generates shear waves in the fluid. Subsequent oscillations in sphere velocity have the same frequency of the standing waves propagating along the square duct which forms a waveguide.

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