If a light hot block solution is set near the top surface of bulk water, the solution may enlarge beneath the surface owing to the thermal buoyancy. The heat diffuses very faster than the solute and then the density of chilled solution becomes larger than bulk water. Therefore, the solution moves downward with fingers. Numerical analyses of fingers in an enclosure were carried out for a three-dimensional flow by using the finite difference method. Calculations were carried out at the Prandtl number Pr=6, the Lewis number Le=100, the buoyancy ratio N_O=0.5 and the Rayleigh number Ra_O=10_6. The light hot block solution enlarged beneath the surface first, especially for the large block solution. In the case of small block solution, the block solution developed to a single salt-finger with a head and tail. In the case of middle block solution, a single finger with four head fingers were formed after the diffusion of heat. However, in the case of large block solution, the solution enlarged clearly beneath the surface and many salt-fingers occurred with time.

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In the melting of high-polymer material on industrial applications, there are unsteady flow phenomena on its non-Newtonian properties. In the difficulty and lack of the experimental investigation, the unsteady interface phenomena in melt-front of high-polymer materials (PP) with several flow configurations (rectangular flow with 5mm & 1mm thickness, with/without artificial surface control) are shown as local and unsteady geographic shape of gas-liquid interface experimentally with the visualization images of high-speed CCD video. From experimental results and considerations, the gas-liquid interface changes its shape properties time-dependently, and the two-way transitions of phenomena are detected, which mean that one is from the center to wall (fountain-flow-like), another is from near-wall to center by non-uniform slipping phenomena just near-wall. These results could be made needful of building the flow and heat transfer three-dimensional mechanism models of high-polymer material flow in ejecting by rectangular flow system.

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This paper presents an experimental investigation on flow and heat transfer characteristics of surfactant solution - air two-phase flow. The test tube is 5.0mm in inner diameter, and consists of the flow developing and heating sections, which are 2000mm and 900mm in length, respectively. Two-phase flow was produced by injecting air into the in-tube flow of surfactant solution (TTAB+NaSa, the concentration is 500 and 1000 ppm). Friction factors and heat transfer coefficients were measured in the heating section (900mm in length). Heat transfer enhancement by injecting air was larger for surfactant solution flow than that for water flow. This indicates that air injection has the effects of not only mixing flow, but also breaking micelle structure for surfactant solution flow.

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In surfactant solution (TTAB+NaSal), the pipe friction factor and heat transfer coefficients were investigated. The straight circular tube of D=5.05 mm in diameter and L=2900 mm in total length was used. In the drag reduction flow, in order to break micelle structures and to promote heat transfer, the "micelle breaker (MB)" was installed in the upper stream of the testsection. The effect of MB was investigated changing surfactant solution concentration (200, 500, lOOOppm). As a result of the experiments, In the case of 1000 ppm, Re=7700, installation of the micelle breaker increased NuPr^<-1/3> at x/D=10 (x/D indicates the distance from heating section.) by 1.9 times compared with the case where it does not install. But The effect of MB mostly disappears by x/D=130. The effect of MB appears so notably that concentration is low.

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The flow drag and heat transfer reduction effects of brine flow with drag reduction surfactants have been investigated in order to conserve the energy in a district heating and cooling system. In this study, Ethylene Glycol (EG) solution with Oleyldihydroxyetyl Amine Oxide (ODEAO) was used as a drag reduction brine solution with surfactant. And the pipe friction coefficient and mean heat transfer coefficient of the EG solution flow with ODEAO were measured as parameters of EG concentration, solution temperature and ODEAO concentration. The experimental results indicated that the flow drag (heat transfer) reduction effect was lost when the wall shear stress exceeded a certain value. And the certain value of this wall shear stress (= maximum wall shear stress) increased with increasing the EG concentration, ODEAO concentration and brine temperature. On the other hand, the drag reduction mechanism of EG solution with ODEAO was investigated by comparing with the experimental results the ODEAO water solution

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A model to simulate the drag reduction by dilute addition of polymer or surfactant (Toms effect) is proposed based on the discrete element model. The dimension of the discrete element, which represents the polymer or the rod-like micelle, is very small compared to that of the velocity fluctuation of the fluid. So it is assumed that the element is in equilibrium state in the fluid and turns to the direction of an eigenvector of the velocity gradient tensor. And the macroscopic effect of the discrete elements is modeled as the stress assuming the elements are independent each other. Direct numerical simulations are carried out with this new model using the rigid dumbbell element as a discrete element model and it is shown that the drag reduction up to 48% drag reduction rate is reproduced.

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In this paper, experiments are conducted to determine the heat transfer characteristics by a square or rectangular (aspect ratio = 4 or 8) nozzle jet impinging obliquely to a plane surface. The impinging angles of the jet relative to the plane surface are 60, 45 and 30 degrees. The nozzle-to-plane distance varies from 2 to 10 times the short side length of nozzle. The local temperature distribution on the impingement surface is obtained by using a liquid-crystal sheet. Furthermore, the velocity and turbulence intensity near the impingement surface are measured by using a hot wire anemometer. The results show a good agreement with the peak points of local heat transfer and turbulence intensity.

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This paper describes the heat transfer and flow characteristics of a heat exchanger tube with high porous material. Copper wire was inserted in a tube. The porosity was from 0.98 to 1.0. Working fluid was air. Hydraulic equivalent diameter was cited as the characteristic length in Nusselt number and Reynolds number. Nusselt number and friction factor were evaluated as functions of Reynolds number based on hydraulic equivalent diameter and porosity. Thermal performance was examined by the ratio of Nusselt number with and without porous material at constant pumping power. The porosity which gave the maximum thermal performance was found by extending the allowable region.

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In the present research, the effect of injection method with porous material is experimentally investigated for the high void fraction gas-liquid two-phase flow of water and steam. As well as the change of a flow pattern with the gas injection method, the effect of the non-condensable gas is experimentally investigated. And the influence on condensation heat transfer is evaluated and considered experimentally. As the results, gas phase is well fragmented by using the porous ceramics to inject the gas phase. Moreover, it is shown that the steam is condensed immediately after the gas injection point even though the gas phase include a large amount of air as the non-condensable gas.

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Dendritic crystal growth of a pure metal material in a melt convection is investigated numerically by applying the phase field model. The assumed flow field is a Couette flow, and a tiny nucleus is exposed in its middle part. The phase field, thermal and Navier-Stokes equations, are solved with a finite differential method. In order to avoid to take account of boundary conditions in a very complex shape, an external force term is added in the liquid phase. The effects of the melt convection upon the dendritic are discussed.

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Spherical silicon can be produced directly by passing molten silicon through capillary with pressurized inert gas. Molten silicon passing through capillary forms jet and the jet is split into droplets by the hydrodynamic instability. This method can produce spherical silicon at ultra-high speed (600-1000 of spherical silicon per second). Spherical silicon produced by this method are known to be generally polycrystalline. Some of spherical silicon consist of 2-4 grains. In this report, we find that the generation probability of spherical silicon with 2-4 grains increased with decreasing cooling rate of spherical silicon. In the early condition of dropping spherical silicon, the cooling rate of spherical silicon was estimated to be between 600 and 800℃/sec

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The experimental study on thermocapillary convection of low Prandtl number fluid was carried out to observe the first transition. The half-zone liquid bridge of molten tin was used as a test configuration. In order to detect very slight temperature changes, the temperature measurement system was improved. It was able to be experimentally detected that the axisymmetric steady flow changes to three-dimensional steady one with increasing the temperature difference between hot and cold disks. At higher temperature difference, oscillatory transition was also observed. Aspect ratio dependence on critical Marangoni number was compared with numerical results. The experimental result of a first critical Marangoni number agreed very well with numerical one.

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Silicon melt flow structure during the CZ crystal growth process, which seriously affects the obtained crystal quality, has been investigated numerically. In this study, effect of crucible size as well as temperature distribution along side crucible wall on the silicon natural convection has been considered extensively by using 3D flow simulation code. If the crucible size is increased, the effect of temperature distribution along the side crucible wall is neglected; the melt flow structure becomes completely three-dimensional and time dependent even if the upper wall temperature is decreased. The macroscopic temperature fluctuation can be easily observed through spoke pattern, which generated at the melt free surface.

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This paper reports on the development of a model of three-dimensional global simulation in crystal growth with magnetic fields. A global model, which contains radiative, conductive and convective heat and mass transfers in a growth furnace of crystal, has been widely accepted for designing a furnace of crystal growth in actual production. Such a global model has been assumed to axisymmetric ; therefore the model imposed the furnace as an axisymmetric configuration. However, actual furnace has three-dimensional configuration, especially for a case with transverse magnetic fields applied. This paper reports the simple algorithms and calculated results of the three-dimensional global model. Such algorithm reports how to couple two-dimensional view factor to three-dimensional one. Moreover, temperature and velocity fields under transverse magnetic fields in a Cz furnace are also presented.

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This paper describes specific features of supercritical hydrothermal synthesis method of nanoparticles. In the method, metal salt aqueous solution is mixed with high temperature water to rapidly increase the temperature of the metal salt solution and thus reduce the reactions and crystallizations during the heating up period. By using this method, we succeeded in the continuous and rapid production of nano meter size single crystals. Specific features of this method is l) rapid nanoparticles production, 2) morphology control with a little change of temperature or pressure, 3) control of oxidation state by introducing oxygen or hydrogen gas, and 4) highly crystallized single crystal formation. By introducing organic reagents in the reaction atmosphere, organic-inorganic fused materials could be synthesized. For the rational design of this process, a thermo^fluid model combined with nucleation and particle growth theory has been developed.

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Site-selective deposition of polymer thin film on well-defined patterned self-assembled monolayers has been paid great attention these days. The purpose of this study is to establish the fundamental technology of site-selective deposition of polymer thin film utilizing wetting contrast of patterned fluoroalkylsilane monolayer (R_f)/silanol(Si-OH) surfaces. R_f/Si-OH patterned surface (line, square) prepared by the VUV-rays or EB lithography have liquidphobic R_f and liquidphilic Si-OH phases, respectively. Polystyrene xylene solution was deposited on the patterned surface with wetting contrast by ink-jet method. The patterned polystyrene ultrathin films were selectively formed on liquidphilic areas.

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The evaporating process of single polystyrene/xylene droplet on a substrate was experimentally studied. The effects of the initial polystyrene concentration (0-3.0 wt.%) and the initial droplet volume (pico litter and micro litter) were examined. Xylene droplet during evaporation was not so affected by the droplet volume, and the shape is nearly circle. However, that for polystyrene/xylene solution was affected both by the polystyrene fraction and the initial volume. The receding speed is apparently heterogeneous for the micro-litter droplet while that is nearly homogeneous for the pico-litter droplets.

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Spreading behavior of ink droplets in a rectangular hollow surrounded by banks were studied by using a numerical simulation. Droplets that collide with the bottom of the hollow collapse vertically within several μs. Then they extend in the radial direction at a low speed. After the outer part of the droplet reaches the nearest hydrophobic bank, it runs up on the bank and retreats, so the droplet extends in the direction of its long side, keeping the width of its short side. When the contact angle on the banked slope is smaller than the slope angle, the progressing side of the droplet becomes concave in the traveling direction.

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In the present work, we investigated experimentally the formation mechanism of the phase separation structures and convection patterns in a layer of an isobutyric acid (IBA)-water binary mixture subjected to vertical temperature and concentration gradients. As a result, the formation mechanism of the polygonal cellular patterns with one droplet formed in a certain range of temperature gradient was speculated to be due to the Marangoni effect along the droplet surface. In addition, it was found that the average diameter of the phase-separated droplets depends on initial concentration gradient.

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Effect of wet-bulb temperature on a drying rate of porous material containing water or sugar aqua solution in high-temperature (160℃) gas flow was investigated experimentally. Glass beads were used as the sample porous material. Mass and surface temperature changes of the sample during drying were measured with a test apparatus, in which wet-bulb temperature could be controlled from 48℃ to 100℃. From these results, it was shown that when the wet-bulb temperature was higher, the drying rate was smaller and the distribution of local sugar concentration was more even in this experiment. Whereas the water in the sample maintained a constant drying rate, the sucrose solution's drying rate decreased gradually after drying was commenced.

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Drying of potato starch paste in hot air, high humid air and superheated steam was examined. Initial moisture content was 0.92kg/kg-d.b., wet bulb temperature of gas flow ranged from 48℃ to 100℃, and gas temperature was 160℃. Temperature and moisture content changes of samples during drying were measured, and cross sections of samples were observed by SEM. The property of dried starch was strongly affected by wet bulb temperature - gelatinization effectively occurred only at higher temperature with water. In addition, the initial condensation/evaporation process in high humid air treatment, based on temperature and moisture content changes, was modeled as reverse process - an important process for material properties for drying.

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Instead of the traditional theoretical thermal efficiency in a combustion chamber [CC], the improved energy conversion efficiencies have been adopted in a CC and a whole engine [WE]. They are named in "the theoretical energy conversion efficiency in a CC (η_EN= [W_<th>/E_<su>] _<cc>)", "the provisional-net energy conversion efficiency in a WE(η_<PN> = [W_<PN>/E_<su>]_<WE>)" and "the estimated net (brake) thermal efficiency (η_<e(ES)>/E_<SU>]_<WE>)". As some points for the improvement, there are the distinctions of the phenomena in a combustion chamber, the adoption of the total energy supplied instead of heat supplied, the adoption of the energy quantity basing the lowest state of a cycle and so on. As a result, some outcomes of the improvement have been able to be gotten. Especially, as a result of analyzing of the Sabathe-type engine, both targets of maximum power and maximum economy have been demonstrated.

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A new visual-oriented numerical method which applies the spreadsheet of Excel has been proposed. In the present study, a programming process on two-dimensional unsteady-state heat conduction problem in the cylindrical coordinate system is explained by way of a specific example, where a short round bar is put under sudden heating on its end and is cooled by forced convection around its side surface. The present unsteady-state numerical calculation has been realized by introducing icon cells in which difference equations concerning the inner and boundary points are embedded. Through the programming process using this specific model, the proposed method is shown to be one of the useful numerical methods.

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A non-iterative approach based on adjoint formulation of conduction heat transfer is proposed to identify the thermal boundary conditions from a transient temperature history measured in a solid body. Using a numerical solution of the adjoint problem, which can be regarded as a numerical Green's function, the temperature at the measuring point can be evaluated under arbitrary thermal boundary conditions. As a result, we can inversely predict the thermal boundary conditions from the measured temperature history by assuming the step-wise profiles of thermal boundary conditions both in time and space.

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This paper presents a method to optimize domain shapes and thermal and flow boundary conditions on mixed convection heat transfer using genetic algorithm (GA) under distributed computing environment based on grid computing. GA increases the probability of finding the global optimum solution and avoids convergence to a local optimum which is a drawback of gradient-based methods. Furthermore, it is possible briefly to reduce computational time because of implicit parallelism of GA. GA method under distributed computing environment is applied to an example optimization problem. As a result, it is found that this method is able to obtain better solution than gradient-based method in less computational time.

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The writer calls a substance ball containing about 10^6 molecules of gas a macroscopic particle. The small balls keep characteristics temperatures and pressures as continuum respectively. We find a pressure equation of gas composed of the particles by classical statistical mechanics.

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As regards the reversible changes of gas having a great number of the particles, various kinds of energy, i.e. free energy, internal energy, etc., are represented by potential flows in the thermodynamics spaces. We obtain some thermodynamic relations under the hydrodynamic condition of continuity as well as the above condition without vortex.

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Influence of Joule-Thomson's effect on thermally-developing forced-convection heat transfer in cylindrical packed beds with uniform heat flux wall was theoretically examined. The effect of non-Darcy, variable porosity, radial thermal dispersion, turbulence and viscous dissipation were taken into account in addition to Joule-Thomson's effect. It is shown that the influence of Joule-Thomson's effect on heat transfer characteristics becomes appreciable as a ratio of the bed-radius to the particle diameter, Reynolds number are increased and that as long as Reynolds number is constant, the heat transfer characteristics increases with a decrease in an inlet pressure.

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This paper suggests a new method of using ultrasound to synthesize bio-diesel fuel (BDF) from vegetable oil. Be different with the conventional method, the new method utilizes ultrasonic sonochemical effect of heating and stunning to promote ester interchange instead of using external heater and stunner. In order to verify the feasibility of the suggested method, an experiment system to produce BDF using both ultrasound and the conventional method was designed and established. Investment of the thermophysical properties of the produced BDF was carried out. Also the experiment of applying the produced BDF to a diesel-engine vehicle for actual driving was performed too. As a result of those experiments, it is confirmed that the method of synthesizing BDF by using ultrasound is reasonable and the thermophysical properties are suitable for diesel engine vehicle.

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Fuel conversion of high moisture content biomass (sludge) was conducted in middle pressure steam at 473K and 1.8MPa by stirring the reactor. In this research, components of solid and gas products were analyzed in order to clarify the mechanism of this system scientifically. As a result, it was found that the calorific value of solid products increased after the treatment. And CO_2 production was promoted during the reaction. This result suggested that an endothermic reaction involving CO_2 production with middle pressure steam was promoted. It was also found that solid product's smell and volume were reduced compared with raw material. Moisture content of solid products was also reduced to less than 30% about 3 days after putting in the desiccator filled with dry silica gel.

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The cellulose powder that was a main component of any woody biomass was successfully gasified with steam, using a sponge-like porous Ni catalyst. The powder was put on the top surface of the porous catalyst packed in a tubular reactor. The reactor was heated through an electric heater. When the powder was supplied into the porous catalyst kept at 800 deg. C, the gasification efficiency for H atom was 120% of the total amount of H including in the cellulose. It was shown that the shift reaction takes place in addition to the gasification reaction.

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A waste gasification system, which is equipped with pyrolysis rotary kiln and gas cracker, is reported. After building a pilot plant first, it advanced to construction of a demonstration plant to a commercial plant, then it became possible to realize processing stabilized as a result. Moreover, much plant data was acquired. In an incinerator, after burning waste, heat recovery is performed, combustion gas is purified after that. On the other hand, in a gasification system, energy use is carried out, after purifying the gasified gas. Since gasification is performed in a hot reduction atmosphere, a possibility that generating of high temperature corrosion and generation of dioxins are controlled is strong. Furthermore, although the amount of calories per unit capacity of the generated clean fuel gas is low, since combining with an efficient power generation system etc. is possible, the improvement in efficiency of generating electricity from waste materials is expected by using this system.

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The gasification system investigated in this research is a two-stage gasification system composed of a shaft type gasification furnace and a reforming furnace. The electric power is generated by a dual fuel type diesel engine. In the experimented, mold bed wastes are used as fuels and the attention was paid to the following three parameters; the sample form, the steam injection effect from the bottom of the gasifier, and the kind of the reforming agent. The influence of these parameters on the composition and the heating value of the generated gas was investigated. The experimental results show that suitable sample form for this system is the pellet form and the steam gasification reaction in the gasification furnace was promoted by injecting steam into the gasification furnace. The heating value of the reformed gas increase 30% or more by using oxygen instead of high temperature air as a reforming agent. The energy rate of the reforming gas supplied to the engine reached as high as 89.6% when oxygen was employed as a reforming agent.

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For soot formation elucidation of mechanism, a Monte Carlo simulation model considering the rate of particle formation and particle size growth rate was constructed. As for particle size growth reaction, sintering of the particles was considered. The relation between particle sintering rate and particle aggregation rate was obtained. In addition primary particle size distribution was predicted. In order to discuss the validity of the model, the soot formation experiment by the benzene pyrolysis was carried out. Soot primary particle size distribution was measured and compared with numerical results. As a result of the comparison, the necessity of particle sintering rate considering the particle viscosity with change of the soot structure was shown.

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An experimental study has been carried out on the synthesis of carbon nanomaterials using rice hulls in methane/air laminar, fuel-rich premixed flames under atmospheric pressure. By placing a pair of porous media on the upstream and downstream sides of the combustion space, excess enthalpy burning was realized to the methane/air mixture. Rice hulls were uniformly scattered on a Ni porous medium that was placed in the combustion space. We have investigated the effects of the equivalence ratio and the burning velocity on nanomaterials growth. As a result, carbon nanotubes were found to be synthesized in non-luminous region.

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Since fossil fuels such as petroleum, coal, and natural gas are limited resources, renewable energy such as solar, wind, and biomass will be needed as substitute fuels. A new type of engine system that uses biomass fuel such as sawdust and rice husk was proposed in this report. A Stirling engine, an external combustion engine, is introduced. The pistons are moved by heating and cooling air in the cylinder. A burner using the biomass fuel heats the air in the expansion room to about 650℃ and a cooling system cools the air in the compression room to about 60℃. The cylinder motion revolves the crankshaft at a rate of 650rpm. The new engine features a traction force of 5HP and a power generation efficiency of 3kW.

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This paper presents a study on the performance of heat exchanger equipped within the APT (Atmospheric Pressure Turbine) system that has been operated on the Inverted Brayton Cycle. The working temperature range is rather low to arise condensation of water vapor at the exhaust gas side. The performance of compact plate-fin type heat exchanger has been examined under the negative pressure region. It has been found that the temperature efficiency more than 95% at the cooling water side can be attained. The pressure drops on both side can also be evaluated.

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This paper reports on numerical assessment of cooling performance of internal ribbed channels in a rotor blade installed in a power generation gas turbine. Roughness functions of heat and mass transfer for fully developed flow in a rectangular cooling channel with two opposite angle-ribbed walls were estimated by using Large-Eddy Simulation (LES). In order to predict temperature profile of the rotor blade, derived correlations of the roughness functions from the LES were applied to the conjugate heat transfer calculation of the blade. As a result, predicted temperature profile on the blade is in agreement with local temperature estimated from material of the spent blade and numerical results presented characteristic variations of the local temperature depending upon mass flow rate of the internal cooling air.

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Electric equipment requires continued miniaturization and ability to dissipate enough heat from these very closely-spaced devices. Heat sink module is popular to achieve additional thermal enhancement. Most heat sink module is designed in two-dimensional shape. In this paper, we propose to design heat sink module in three-dimensional shape.

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A large number of lithium-ion batteries are used inside cell phones, lap-top computers and many electronic devices. Lithium-ion battery is being improved continuously to increase energy density and prolong service life. In this paper, we have examined the effects of ambient temperature on service life of lithium-ion batteries. The maximum service duration is achieved at the temperature of 45℃. To extend the service time of portable devices, keep its lithium-ion battery at warmer condition by using the waste heat from electronic circuit.

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This paper deal with the film cooling effectiveness of round and shaped hole on the suction side of the airfoil under transonic condition. The measurement with heat - mass transfer analogy has been conducted at linear turbine cascade facility to investigate the effect on film cooling effectiveness due to varying exit Mach number and blowing ratio. Shock boundary layer interaction scarcely has influence on the film cooling effectiveness, and film flow is hard to diffuse in the lateral direction under transonic condition. In addition, the comparison between these experimental data and the results with CFD (Computational Fluid Dynamics) is reported.

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This paper presents an experimental study of film cooling on a flat surface using swirling jets through a row of discrete holes of 45° along streamwise direction. Experiments were conducted in a low speed wind tunnel and swirling jet was made by a twisted tape set in the injectant path. A thermal probe with thermo-couples was used to measure both film cooling effectiveness and dimensionless temperature. Three pairs of swirling jets were used, i.e., "clockwise-counterclockwise", "counterclockwise-clockwise" and "counterclockwise-counterclockwise". Furthermore, the pitches of swirling tape in the injectant path were also changed. The results show that the swirling jets for film cooling improve both distributions of film cooling effectiveness and dimensionless temperature on a flat surface.

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In order to elucidate the mechanism and characteristics of boiling heat transfer in a micro-channel vaporizer, the experimental investigation of the micro-layer thickness that formed between the heating surface and vapor generated was essentially needed. In this report, the micro-layer thickness was measured applying the laser extinction method for the channel gap sizes of 0.5, 0.3 and 0.15 mm. The process of bubble growth was recorded with a high-speed camera simultaneously. It was confirmed that the gap size, the rate of bubble growth and the distance from the incipient bubble site have an effect on the micro-layer thickness in a micro-channel boiling system. The initial micro-layer thickness increased with increase of the velocity of bubble forefront to moderate value of the velocity. In the region of larger velocity, the thickness was constant for each gap. The distributions of the initial thickness of micro-layer were shown.

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The unsteady measurement of liquid film thickness is essential to investigate liquid film structure in the two phase annular-mist flow and especially to establish the dry out mechanism of liquid film on fuel rod around spacer in the new fuel assembly of BWR. The basic experiment is conducted to multi-points resistance probe to measure liquid film thickness profile in flow single channel with same cross-sectional configurations. Influences of spacer in rod gap on the liquid film thickness were clarified experimentally.

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For making clear the phenomena on the unsteady heat transfer with liquid film in two phase flow, the measurements are needed about unsteady velocity profiles and film thickness in the liquid film adding time-averaged values. It would be important especially to estimate the dry out mechanism of liquid film experimentally on fuel rod around the spacer in the new fuel assembly of BWR. In this study, the unsteady velocity profiles would be estimated by the surface and flow velocity profiles, which were detected experimentally by the tracking of the visualizing particles with image processing. In addition, for estimating of liquid film thickness, we have tried to measure 3D representative velocity profile by main & sub cameras.

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From a viewpoint of software side, the snow is one of the mysterious materials for almost passengers visiting snowy country from hardly snowfall area. When they encounter with the snow, they may be felt the impulse to touch the snow, to realize coldness and to be charmed by the snow. There are many voices that they would like to have this mysterious experience even during midsummer. In order to respond to those needs, the authors planed to construct a small space enclosed by snow walls, and developed a technique that prevents snowy dissolution under hot condition with the aid of refrigerator. With this technology, a project that makes a small space enclosed with snow walls in midsummer was carried out with the member of the Sapporo Commerce-and-Industry Meeting in this summer, and we also have been enjoyed.

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The execution example of snow-melting system using ground heat was introduced. As a TRT result, the effective thermal conductivities of soil were 1.92W/m・K in A-district, 1.79W/m・K in B-district. The heat extraction from thermal exchange bore hole with single U-single-tube type of depth 100m was 69.5w/m. The heat extraction from thermal exchange bore hole with duble-tube type of depth 150m was 59.2w/m. It guessed this difference by nature of soil and ground water.

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Geo Power System is a natural air-conditioning system for residential and commercial premises, using geothermal energy available beneath the ground surface at a depth of 5 meters. Geothermal energy can be explained in simple terms as the thermal energy available at a depth of 5 meters below the ground where the temperature remains stable all round the year between 15-18 degrees Centigrade i.e. 59-65 degrees Fahrenheit. It is intelligently designed to ventilate the interiors to all corners and to effectively enhance the internal conditions by removal of formaldehyde which is harmful to ones health. This system provides natural environment-like conditions to oneself, increases house life and protects the environment.

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An original thermal solar-panel is studied as a useful device for effectively utilizing solar thermal energy. Decompression-boiling system can perform as an efficient heat-transport device with almost no heat loss because of the compound heat transfer process of boiling water at low pressure and latent-heat transport with small temperature difference. This system is expected to be applied not only for solar system but also in wider application using low temperature or small temperature difference resources. The indoor experiment proved that its high heat-transport performance of higher than 85 % even at high thermal-input of 1 kW/m^2 and its stable heat-transport performance by adding a surface-active agent into water.

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The instability of hydrogen-air premixed flames propagating in a narrow space is investigated using two-dimensional numerical simulations with the heat loss of Newtonian type. The numerical model contains detailed hydrogen-oxygen combustion with 17 elementary reactions of 8 reactive species and a nitrogen diluent, compressibility, viscosity, heat conduction, and molecular diffusion. A sufficiently small disturbance is superimposed on a planar flame to obtain the linearly most unstable wave number, i.e., the critical wave number. To investigate the characteristics of a cellular flame, a small disturbance with the critical wave number is superimposed. Owing to intrinsic instability, a cellular-flame front is formed. With an increase in the heat loss, the cell depth and burning velocity of a cellular flame becomes smaller, which is due to the decrease in thermal expansion.

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