A ladder of the ladder truck with the lift mechanism often generates a vibration at the time of the lift operation. This paper describes the simulation analysis of the dynamic behavior of extension motion and elevation motion which are one of the lift mechanism in order to make clear its vibration phenomena. We make the dynamic analytical model composed of 2 sections ladder using Multibody Dynamics. An equation of motion is derived using differential algebraic equation (DAE). We investigate the validity of our proposed simulation analytical method by comparing the simulation results with the experimental ones.

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Recently, the houses and offices in which stairs elevators such as a chair-type are installed on from the 1st floor to the 2nd floor have been increasing along with the fulfillment of a welfare machine. This paper describes the preliminary investigation of the vibration control to secure the comfortability of a stairs elevator. A stairs elevator is considered as a moving body restrained on a three-dimentional orbit. Its dynamic behavior is analized by two methods of ODE and DAE. The accelerations in simulation are compared to those in experiment.

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A serial printer using a synchronous belt in the print-head carriage system sometimes generates a vertical striped pattern in the printing image. This is known as jitter and caused by vibration of the print-head carriage system. In this paper, the relation between the jitter and the carriage's vibration is analyzed experimentally. It is found the jitter does not depend on the carriage's vibration only, but also on the density of printing image. A method with which the jitter level can be estimated is proposed. The jitter level is defined with density fluctuation ratio and a commercial image scanner is used to measure the density of printing image.

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Outer Adiabatic System Using "Green Eco-Mat" is composed of the porous mats laid on the roof and housetop and the water supply equipment. It is able to conserve energy throughout the year, namely, to radiate heat by vaporization of saturated water in the summer season, and to keep the houses warm like adiabatic slabs in the winter season. This paper presents the results of performance tests and evaluation of energy conservation effects. It is expected that this system saves the electric power of 60kwh for 8 hours in the daytime to air-condition the building with 500m^2 in roof area.

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CF_4 is one of the most stable gases among semiconductor processing gases and their decomposition is extremely difficult. Influence of frequency of radio frequency (RF) power on decomposition of CF_4 using inductively coupled plasma (ICP) reactor at low pressure was investigated. The frequency of RF power supply is 2MHz or 4MHz. With each frequency, complete decomposition can be obtained with certain operately conditions of ICP such as the total flow rate, the ratio of CF_4 to O_2,and RF power. The detailed discussion is presented in this paper.

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Thermo-sensitive liquid-crystal suspension method was applied to investigations on 3-D structure of natural convection in an inclined rectangular cavity heated from below and cooled from above. This method could give relevant quantitative information of temperature and velocity distribution in the flow field by using color image processing and spatio-temporal correlation method. Then the 3-D structure of the natural convection in an inclined rectangular cavity was well identified.

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High intense pulsed neutron beams are generated by nuclear spallation reaction at the target system in JPARC project. This paper describes thermal hydraulic designs of plate and rod targets to realize the validity and safety on the solid target. The neutronic performance of each target was compared with the average densities of the designed targets. The density of the plate was highest, that of the rod was the second and that of mercury was lowest at 1MW. Moreover, considerations about the decay heat of a target were performed. Since the decay heat of tantalum is high and its attenuation rate is small, the tungsten plate target HIPed with tantalum was required special cooling methods during the target exchange. A present most realizable target is the tungsten rod array target sheathed by stainless steel or zircalloy.

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This paper describes the thermal analysis of Printed Circuit Board (PCB). Because the modeling of PCB has hitherto been very poor, the thermal simulation results cannot satisfy the required accuracy. To solve this problem, we divide into each layer that constitutes the PCB, and considers that each layer is a homogeneous material. And the thermal conductivity of every layer is computed with reference to the wiring area ratio. However, by this method, the anisotropic thermal conductivity of PCB cannot be modeled. Then we divide the PCB into a set of blocks and computed each thermal conductivity in consideration of the wiring area ratio and the wiring direction with reference to the wiring diagram, and created the analysis model reflecting the anisotropic thermal conductivity of PCB.

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Functionally Graded Materials (FGM) have been developed as the material which can stand at high temperatures. FGM is a nonhomogeneous material and an information about distribution of thermophysical properties is demanded to evaluate its heat resistance. So we develop a new method to measure thermophysical properties using stepwise induction heating. The method uses an approximate solution by the Finite Element Method (FEM) for the data reduction on the assumption that FGM is a multiplayer material composed of various substances differing in property. A double layer materials is regarded as a multiplayer materials in fundamentals. This report describes analyses of heat conduction to verify an effect of thermophysical properties on a temperature profile at surface.

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At present, regulations of automobile exhaust gas in each country are regulated by the total mass emission (g/km) of gas compounds, such as CO, THC, and NO_x. For measurement of mass emission, the CVS(Constant Volume Sampler) method has been in general use. However, as a result of the low emission levels of new engines, the CVS method in no longer able to meet today's requirement. The reason is that the CVS method requires a high dilution to prevent water condensation, this leads to measurement of very low gas concentrations, which results in worse accuracy. In consequence, it comes to need that exhaust gas concentration is directly measured in the tail pipe without diluting. This study focused on the flowmeters (Annubar^[○!R] flowmeter, vortex flowmeter, ultrasonic flowmeter) which are now used as exhaust gas flowmeters, and certificated the basic characteristics of these flowmeters at steady flow and pulsating flow.

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For the prediction of annual mean concentration distribution of air pollutants in mesoscale area it is too expensive to accumulate instantaneous values predicted by a three-dimensional unsteady model. In this study we aimed to develop a numerical model, which uses annual mean statistics of wind, emission intensity and so on as inputs, and outputs annual mean concentration distribution. The focus was located on the estimation of horizontal diffusion coefficient. This model was applied to the prediction of annual mean concentration distribution of NOx in Kanto area. The results are compared with observations and the results estimated by an unsteady model.

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Recently vehicle exhaust gas purification systems are going to be developed to prevent air pollution near the roadways. To equip such a device effectively, it is necessary to get a clear picture of diffusion behavior of exhaust gas on the roadways. In this study, the behavior of exhaust gas diffusion from moving vehicles were numerically investigated by Large Eddy Simulation(LES). As the first step of it turbulence intensity, stream line and pressure distribution of mean-flow obtained by LES were compared with existing wind tunnel experiments to evaluate the reliability of air-flow calculation. Fluctuation and distribution of concentration were also investigated.

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A regenerative thermal oxidizer was applied to the processing of exhaust gas from a mud incinerator, and the stack CO concentration of 100 ppm or less which depends on dioxin regulating methods was attained. 92% or more of a heat recovery rate was attained through heat exchange using a regenerator. And, a dramatic reduction in fuel costs was achieved. Moreover, an examination was carried out to process tar contained in exhaust gas and a stable operation was achieved.

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For Volatile Organic Compounds (VOC) containing toluene from a paint booth, styrene, etc., a Regenerative Catalytic Oxidizer (RCO) was supplied by Babcock-Hitachi K.K., and 98% or more of the rate of VOC decomposition was attained. Moreover, 95% of the heat recovery rate in a ceramic honeycomb and 250 ppm (toluene equivalent) of self-combustible concentration were realized, and it was proved that Regenerative Catalytic Oxidizer supplied by Babcock-Hitachi K.K. was excellent in energy-saving characteristics.

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The coolant oil, which was widely used for machining various metal pieces from various industries, neads to clean before reuse it. The present study focused on the coolant oil treatment for machining aluminum using electrochemical methods. More than 90% of fine aluminum particles, grease and oil were removed.

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Sulfur dioxide emissions and depositions in East Asia are changing by a year. Long range atmospheric transport model has been used to compute yearly average values of pollutant concentrations and depositions. In the study source-receptor relationships of sulfur dioxide by a year are investigated. Sulfur dioxide emissions in China are very large for every year, and they influence acid depositions of other countries in East Asia. The sensitivity of dry deposition rates to dry depositions was also investigated. Their results weren not so much different each other. The caluculated annual averaged dry depositions of sulfur dioxide are generally within a factor of two of measured values.

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Although expanded polystyrene (EPS) is indispensable to our lives, it is not reused sufficiently. In older to solve the environmental disruption, an equipment for reduction of volume of EPS was developed in this research. Heating method using a cyclone was introduced for the simplicity of mechanism and facility of maintenance. Supplying separately EPS and heating air from different two ports and coating Teflon on inner surface of cyclone, most difficult problem on adhesion of melted EPS on the wall was solved.

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The basic experiment is performed for investigating the difference in the turbulent diffusion in neutral ambient fluid and stability stratified ambient fluid. The axial velocity compornents u and the concentration c of fluorescein sodium were measured simultaneously in turbulent buoyant jet, using laser-Doppler velocimeter (LDV) and laser-induced-fluorescence (LIF) device. Each result for neutral and stratified ambient is compared and considered.

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The operational strategy for cost saving is investigated for an existing gas turbine cogeneration plant with steam injection and inlet air cooling whose operation is difficult to be determined because of its high flexibility. An optimization approach is adopted to acquire the knowledge for the rational operational strategy. The on/off and rated/part load status for each piece of equipment, the amount of injected steam, and the on/off status for inlet air cooling are determined so as to minimize the hourly operational cost subject to the performance characteristics of equipment and energy balance relationships. This optimization problem is solved for various combinations of power and steam demands under various ambient air conditions. The operational strategy such as the on/off status of the cogeneration units, auxiliary boilers and the inlet air cooling as well as the steam injection is illustrated by operational maps, which clarify the conditions for the effective use of steam injection and inlet air cooling.

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The authors think that the wind turbine with sail wings is available for utilizing the wind blowing between buildings. This paper indicated the experimental results on the sail wing type wind turbine and the propeller type one. Because of low rotational speed, the wind turbine with sail wings could not charge the battery. But the wind turbine with sail wings is supposed to have the characteristic of large rotational torque. This characteristic may be useful for consuming the wind energy directly.

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A small wind power generator carries out the right pair of the direction to a wind direction in order to obtain a high output. However, the maximum output is not always obtained by a sudden change of wind velocity or a wind direction and by the time delay of number-of-rotations changes or change of direction of a windmill in fact. In this paper, we evaluate the influence which a wind direction and wind velocity change do to a power generation output of a small wind power generator etc. using the data which was obtained from the small wind power generator of existence.

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Recently, polymer electrolyte fuel cells (PEFC) have been developed actively in many research laboratories and companies as an environment-friendly power source. One of the important factors determining the performance of a PEFC is a membrane electrode assembly (MEA). In this study, various making processes of MEA were tested and the effect of the MEA on the performance of a PEFC was investigated experimentally. As a result, an original, easy making process (Cast Process) of a high performance MEA with three-dimensional catalyst layer was contrived.

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Fully developed turbulent flow in a rotating channel is simulated numerically using LES and DNS. Especially, prediction of re-laminarization at suction side is discussed. Our SGS model of one-equation dynamic type is compared with the conventional Smagorinsky model. The representation of subgrid scale turbulence in the vicinity of the suction side is significantly improved by our model in comparison with Smagorinsky model. Agreement with DNS database is also satisfactory.

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The Boussinesq and non-Boussinesq approximation is compared for the direct numerical simulation (DNS) of turbulent flow in a horizontal channel with thermal stratification. The low-Mach number method is applied as one of the non-Boussinesq assumptions in our study since basically the same numerical scheme can be applied for both cases. The DNS results suggests the Boussinesq assumption cannot represent the asymmetry of turbulence properties especially when the near-wall events such as sweep and ejection are within the strong temperature gradient.

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The purpose of this paper is to show the experimental results concerning with the drag reduction of square prisms due to the cutout of the rectangular shape at their front edges. The drag coefficient, the lift coefficient, the Strouhal number, and the base pressure coefficient are measured for various angles of attack from 0°to 25°and for various length and breadth ratio from 1 to 4. The velocity distribution around the square prism is measured by X-type hot wire anemometer. The present experiment shows : (1) The cutout of the edges is very effective. (2) The effect of the drag reduction due to the cutout is large near the zero angle of attack, and the drag coefficient becomes small more than that of the circular cylinder. (3) The global flow in the wake around the prism with the cutout is almost the same in the case of various length and breadth ratios

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This paper deals with an experimental study on the fluid flow around two circular cylinders in various arrangements. The surface roughness the of two cylinders was changed respectively. The experiment was carried out in a wind-tunnel with a working section 300mm×50mm×500mm, the ratio L/D of the spacing L between the two cylinders centers to outer diameter D of cylinder the was 1.75 constant. The surface-pressure distributions on the circular cylinders were measured in the range of Re=0.57×(10)^4∿6.63×(10)^4 and the drag and lift coefficients were determined from these measurements. The velocity in the wake was measured with a hot-wire anemometer. The flow patterns around the two circular cylinders were visualized by a smoke tunnel. As a result, when the two cylinders with rough surface were by compared to the two with smooth surface, it was found that the drags of both cylinders were decreased in smooth case.

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Pipe flow transition of a dilute surfactant (C_<14>TABr) water solution was investigated by pressure loss measurement, LDV measurement and flow visualization. The experiment was carried out using straight glass tubes with a inside diameter of 5.02 mm and a total length of 2712 mm. Large perturbation necessary to produce a turbulent patch was provided by a ring-shaped roughness element, installed at the entrance region of the straight pipe. It was found that surfactant additives beyond a concentration of 300 ppm clearly increased the critical Reynolds number. It was also found that the turbulent patch generated by the roughness element turned into turbulent puff at larger concentration than 300 ppm.

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Effective viscosity of bubbly two-phase flow is experimentally investigated by means of falling sphere method. The terminal falling velocity of the sphere is measured by image processing to calculate the relative viscosity of the two-phase flow to the single-phase flow. The measurement results show that the effective viscosity depends on not only void fraction but also bubble frictional Weber number. Effective viscosity decreases as void fraction increases when We number is larger than critical We number at 6.63. This fact implies that the reduction of the effective viscosity is explained by the deformation of the bubbles.

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Although the amount of nonwoven fabric produced has been increasing for the last fifty years, but the ratio of the amount of nonwoven fabric used to the total amount of fiber used does not exceed 20%. It is important to consider an application of nonwoven fabric to new industrial products. The purpose of this study is to investigate the effect on the drag reduction in a circular pipe flow by means of the inside wall coated with the nonwoven fabric. Three types of nonwoven fabric used in this experiment are an electret one made of polypropylene. The diameter of the fiber is approximately 4 to 30μm, the fiber distribution of these types is a random laying. The pressure drop was measured for various Reynolds numbers. It was proven that the inside-wall coated with the nonwoven fabric has the ability to reduce the drag in the circular pipe flow.

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When many small bubbles are injected into a liquid turbulent boundary layer, the drag on the wall is reduced noticeably. It is important to clarify the process of bubble formation from air jet because the drag reduction is strongly dependent on the bubble size. In this report, the behavior of airflow was carefully observed near a small orifice on the wall. The orifice diameter d_0 free stream velocity U_∞ and airflow velocity v_0 were varied as d_0=0.2m/s, 0.4mm, U_∞=1&acd;4m/s and v_0=10&acd60m/s, respectively. When v_0 is quite large, the airflow forms a cylindrical jet which elongates in the free stream direction. The observation by use of high-speed video camera shows that the airflow from the orifice impinges into the separated bubble and coalesces. The cylindrical jet with periodic knots on the liquid-air interface is formed by the repetition of above process.

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It is known that turbulent drag is reduced at algae planted wall. We think that algae interact with turbulent flow in specific wave number domain. The drag reduction effect by means of Direct Numerical Simulation (DNS) with simplified model for algae in fully developed turbulence flow field, we increase the resistance force of transverse direction near the wall in specific wave number domain. Our results suggest that the spanwise damping in lower wave-number domain is more effective for drag reduction, but also that the operation at very restricted scale is not satisfactory.

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A method is described to solve the time dependent incompressible flow with finite difference method on curvilinear moving grid in three dimensions. The scheme is fourth-order accurate in space and uses the momentum equations for the velocity coupled to a Poisson equation for the pressure. The fourth-order consistent scheme is applied to the convective terms in the Navier-Stokes equation. In this investigation, the flow around periodic bending flat plate is computed. As the results of this investigation, drag and lift force around deformating plate can be estimate. It is also demonstrated that fractional step method are required to advance the solution from n to n+1 instead of the rezoning method.

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Numerical simulations are performed using a deformation grid to investigate a propulsion mechanism of deformed hydrofoil profile. The shape of the hydrofoil profile was chosen by NACA04 type hydrofoil. Hermit and transfinite interpolations are used to generate internal grid points. This method can eliminate the overlaid grids at large amplitude. A fractional step method using implicit numerical viscosity is adopted for computational efficiency. We compared six kinds of thickness about difference of propulsion power. And it is clear that the non-dimensional thrust power increases with decreasing thickness.

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In this paper, the drag of a highly water-repellent wall sphere were studied by applying the flow visualization technique and measuring the fall velocity in Newtonian fluids. The terminal velocity of the highly water-repellent wall sphere decreased in comparison with that of the normal smooth sphere and the maximum drag reduction ratio was 14.6% for the highly water-repellent surface at Re=93.2.

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Solid particle may be a possible device for controlling the turbulence transfer of momentum and heat. We applied the direct numerical simulation (DNS) to investigate the particle-laden turbulence in fully-developed upward flow in a vertical channel. In this report, particular attention is focused on the influence of particle rotation. Rotating particles are distributed more uniformly in the channel in comparison with irrotational ones. Flow separation from irrotational spheres develops to hairpin vortices in near-wall region, while flow around rotational ones increases small scale turbulence in the mainstream region.

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A particle cluster formed in a riser of the circulation fluidized bed or duct line of an air transportation device gives big influence to both a Gas-Solid phase and correlation of various kinds of transportation phenomena. Therefore we investigated flow structure of a cluster numerically. In case the inter-particle collision is calculated, the deterministic method has the fault that calculation load becomes large. Then, some probability methods are proposed. The DSMC method was in one of them, the DSMC method is a method used for the molecule collision simulation in dilute gas, and there was no study about calculation accuracy of DSMC method applied to dilute Gas-Solid flow. This study examines the problem and validity of application of the DSMC method to dilute Gas-Solid flow.

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The purpose of this study is to develop phase separation equipment using a simple impacting T or Y-junction for gas-liquid two-phase flow under microgravity. In order to clarify the effect of tube diameter on the phase separation performance, phase separation experiments in the T (θ=90°) and Y (θ=60°, 30°) junctions of 4 mm ID set in a horizontal plane were carried out using air and water as the working fluids. Moreover, the effect of the flow direction of the inlet flow was evaluated. The phase separation performance was also improved by decreasing of the angle θ between the inlet and the side branch as well as our previous results on junction of 10 mm ID. However, phase separation was not performed for the high gas velocity condition in which the inlet flow regime was an annular flow.

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Fundamental forms of regression functions are proposed for large bubble lengths, liquid slug lengths, distances between a large bubble and the following large bubble and large bubble period of gas-liquid-solid three-phase slug flow in vertical pipes. They are composed of ratios of volumetric flux, viscosity ratio, density ratio, the Froude number, the Reynolds number, and the Weber number. Empirical regression functions were obtained using the experimental data of air-water-ceramic spherical particles three-phase slug flow in the vertical pipes with their diameter 20.9-50.4 mm. Diameters of solid particles are 1.14-24.8 mm and their densities are 2370-2400 kg/m^3. The values of coefficient of determination of their regression functions are larger than 0.95 and the estimated values agree well with the experimental results.

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Experimental and numerical studies were made to investigate the effects of liquid film to gas-phase turbulence modification on annular flow. By using the hot-wire anemometer, time averaged axial velocity profile, turbulence fluctuation profile, energy spectrum, and auto-correlation coefficient of gas-phase axial velocity component are measured. By using the point-electrode prove, the time-averaged liquid film thickness is also measured. Considering the effect of wavy interface of liquid film, numerical simulations for gas-phase turbulence structures in annular flow are carried out. Liquid film is assumed and modeled to be the surface roughness of the wall moving with the velocity of liquid film.

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Simultaneous visualization is carried out for settling fine copper particles and fluorescent tracer particles in turbulent water flow in an open channel. PIV and PTV techniques are applied to the images of the scattered light from the copper particles and those of the fluorescent light of the tracer particles, respectively. In order to determine the hairpin vortices from the images, the motion of tracer particles around the hairpin vortices has been predicted by using the database obtained by direct numerical simulation (DNS) for turbulent channel flow. It is found that the life-up of hairpin vortices is attenuated by the depositing copper particles. The clusters of copper particles are found to be sustained in convergence-dominant regions of main flow.

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In the present study effects of pressure drop of a distributor on particle motion in fluidized beds are studied empirically and numerically. The Discrete Element Method (DEM) is employed to calculate the motion of individual particle. The predicted pressure drop of the disributor reguired to achieve uniform flows agreed well with previous empirical findings.

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We have studied motion of plugs in a standpipe by a DEM simulation. We developed a simpler one-dimensional granular flow model than DEM from the detailed information about the plug motion predicted by the DEM simulation. It is shown that the proposed flow model can express coalescence and brakeup of plugs qualitatively. It can reduce drastically the computational load.

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The flow nearby a suction-pipe intake used for a manganese mining system is very complicated. we have to suck up particles efficiently, over wider range around a suction pipe. In this research, on purpose to clarify the sucking characteristics and the flow near the suction-pipe intake, the authors investigate experimentally about the case where a coarse particle sucks up. First, in order to clarify the mechanism of a particle behavior, the authors measured suction force acting on the particle. Furthermore, in order to clarify the influential range and the characteristics of the suction force, the authors measured the critical condition to attract a particle. Finally, in order to know the flow near the suction-pipe intake, the visualization by the smoke-wire method was conducted. As a result, (i) the suction force becomes maximum at r_s/D&cong;0.2,(ii) density ratio influences the critical condition to attract a particle, (iii) near the suction-pipe intake, the flow is nearby potential flow.

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A large side load was observed in the supersonic nozzle of the LE-7A rocket engine during startup and shutdown transients. In the present paper, the subscale test and the three-dimensional numerical simulation are carried out to investigate the flow field in the compressed truncated perfect nozzle. The experimental and numerical results show good agreement. The numerical results show that the interaction between the internal shock and the Mach disk cause the cap shock pattern. The separation pattern in the testing nozzle is a free shock separation (FSS). The numerical result predicts the side load does not become large under the FSS condition.

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A large side thrust was observed during start up and shut down transients in the nozzle of the LE-7A rocket engine. The objective of the present paper is to clarify the mechanism producing the large side thrust. In this paper, two-dimensional simulations are performed. Several types of nozzle are simulated and the flow fields are compared. Furthermore, the nozzles with step are simulated to investigate the effects of the film cooling injection step.

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We consider line sink flow in a reservoir of finite depth. When the fluid is stratified in the vertical direction, only a layer of fluid adjacent to the sink level is withdrawn. This phenomenon is called selective withdrawal, and there exists wide application to water quality management. We here describe the effect of selective withdrawal when the line sink moves in a horizontal direction.

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