This paper reviews the present state of heat transport devices of the oscillating-flow type. First, outlines of uses, required characteristics and desirable new functions of heat transport devices are given. Next, heat transport devices are categorized into some groups based on the principles of enhanced heat transport. Finally, the present state and remaining issues of oscillating-flow heat-transport devices such as SEMOS (Self-Exciting-Mode Oscillating-Flow) and COSMOS (Counter-Stream-Mode Oscillating-Flow) heat pipes are summarized.

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Thermal characteristics of laboratory- and practical-scale latent heat thermal energy storage tanks are investigated experimentally and theoretically. Commercial paraffin wax as the thermal energy storage material is packed in the tanks. Cloths made of high conductive carbon fibers are installed in the tanks to enhance the heat transfer rate in the tanks. Experimental results show that the thermal characteristics of the tanks are improved with increasing volume fraction of carbon fibers. A numerical model is developed to predict the thermal characteristics of the tanks. Optimum volume fractions of carbon fibers added in the tanks is numerically discussed.

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In this study, the heat transfer with combined the natural convection of air around tubes with the melting of phase change material inside tubes were studied numerically and experimentally. Two horizontal elliptical tubes were arranged in-line. These tubes were immersed in air quietly. Numerical result was compared with experimental data. Results are presented as melting characteristics of phase change material, temperature distributions, flow patterns and melting fraction.

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In air-conditioning, it is desirable that liquid-solid phase change temperature of a cold energy storage material is around 10 degrees Celsius from a viewpoint of the improvement of COP. Moreover, the thermal storage material that forms slurry can realize large heat capacity of working fluids. Since the solid adhering to the heat transfer surface forms a thermal resistance layer and reduces the rate of cold storage remarkably, it is important to avoid the adhesion of thicker solid layer on the surface for realizing the efficient energy storage. Considering a harvest type cooling unit, the force required for grabbing off the solid phase from the heat transfer surface was studied. Tetra-n-butylammonium Bromide (TBAB) clathrate hydrate was used as a cold storage material, The effect of heating surface material on the adhesion of TBAB hydrate to the heating surface was examined experimentally.

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In this paper, the effect of electric field on the trapped and swept phenomena of dissolved gas due to freezing has been investigated experimentally. The ice layer including gas is strongly influenced by the existence of electric field, the freezing direction and the freezing rate. The diameter of gas bubble trapped in ice layer become larger in the case of applied electric field because the coalescence of gas bubbles was promoted by the applied electric filed.

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The amount of cold heat stored in the snow storehouse and the heat transport phenomena are studied experimentally. The results show that the amount maybe estimated by assuming the density of the stored snow 0.613 kg/m^3. And it is showed that the most of heat flow from the surrounding soil and air transfered by the radiation. So, the surface of the inside wall of the house would be courted by the low emissivity materials.

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Because of employment of highly advanced earth observation sensors and employment of superconducting devices for communication equipment, number of missions with multi-cryocoolers tends to increase. Therefore, it is necessary to establish fundamental researches for space cryocooler development of small lightweight, high performance, high reliance, and a long-life. As the cooling system which responds to such a background, thermoacoustic devices attract attention. The attempt that uses a thermoacoustic engine for the pressure wave source of a pulse tube refrigerator is suggested, and if realized, application in space field is expected. In general, thermal compressors need a long resonance tube. Therefore, the system which operates solid displacer as resonator instead of a resonance tube was proposed. Though a great miniaturization of the device was achieved by adopting displacers, power loss in a displacer part became large, and a result which causes decline in efficiency was brought. Then, in this paper, the influence of displacer piston weight was investigated using three kinds pf displacers.

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In the present report, thermal performance of a thin heat spreader composed of a COSMOS heat pipe and a dual piezo pump was experimentally investigated. The result indicated that, for temperature gradient of about 500K/m, the heat transport rate of this heat spreader was as high as 20W and the rate of pumping power to the heat transport rate was about 0.18%.

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The heat transfer from the condenser of a heat pipe installed vertically in the heat storage tank which stores a natural cold heat in winter is studied experimentally. It is proved that the heat pipe doesn't transport a heat to the water of the tank and is able to transport only from the water of the tank to the condenser. The heat transportation from the condenser to the ambient mainly depends on the radiation heat transfer, so the estimation of the temperature of the sky is necessary to design the optimum heat storage tanks

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Flow and heat transfer characteristics were examined experimentally on vertical flexible channels in a heat exchanger simulating the thermal energy storage tank with PCM rod capsules. The channels were formed as the gaps, which were composed of 7 flexible circular heating rods, 34 mm OD. x 1.5 m high, packed vertically in a tubular container of 104 mm ID. One rod in the center of the container was surrounded by the other 6 rods. Difference between the water flow rates in 6 smaller channels (around the central rod) and in the other larger ones (composed of the outer 6 rods and the container wall) was much smaller than expected. This showed the existence of the cross flow between the inner and outer channels caused by the deformation of the rods. The heat transfer rate was increased by about 25 %, which might be due to the heat transportation by this cross flow.

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In Japan, effective utilization of waste heat from power and production plants has become very important to restrain output of CO_2. But it is difficult to use waste heat on site or very near by. Because waste heat from power and production plants is too many value to use for heating and cooling applications on site. We need the method to transport waste heat to heating and cooling applications of other site. Kobe Steel Ltd. is developing latent thermal energy storage equipment for this transport system. This equipment used Erythritol of phase change material (PCM) and direct contact heat transfer technology. Direct contact heat transfer technology is heat exchange method contacted heat medium to PCM. The advantage is high performances of heat input and heat output, light weight equipment by no heat exchanger. In this time, the authors estimated the performances of heat input and heat output by experimental equipment including Erythritol of 15kg. As the result, the authors succeeded high performances of thermal energy storage and stable running by this equipment. We show the performances of these systems for latent thermal energy storage.

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Heat transfer characteristics and critical heat flux of a micro grooved evaporator were examinated experimentally, and effects of liquid subcooling were mainly investigated. We used 6 kinds of grooved surfaces with different groove width (0.2mm and 0.3mm), depth (0.5mm,0.6mm and 0.7mm) and spacing (0.2mm and 0.3mm). Also, the evaporating front of thin liquid film was observed and the relations between meniscus and the heat transfer characteristics were investigated.

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For usage of relatively low temperature wasted heat, a steam-driven water piston engine was planned and simulated. This engine was driven by expansion, condensation and compression of steam with oscillation of water head in the cylinder. It was shown that continuous steam supply resulted in an unstable behavior of water piston, and that intermittent steam supply improved the stability of the engine.

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A new distillation/concentration system using heat pump is originally proposed and confirmed the actual performance of this system by using a small-scaled glass-made apparatus. The experimental results are reported here. We observed that water strongly boils even at temperatures below 40℃ by decompressing inside of the apparatus. The efficiency of distillation is superior to earlier studies. The amount of distilled water increases with decreasing temperature of cooling water, while the efficiency becomes lower. Heat balance calculation taken in consideration of temperatures of heat-source and -sink with the ambient temperature would be required as a next problem for operating it under optimum conditions.

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Subcooled flow boiling of water was performed in a horizontal rectangular channel with a small heating surface of 10 mm square placed at the bottom of the channel. Microbubble emission boiling (MEB) occurred in transition boiling region and the heat flux increased extremely higher than the ordinary critical heat flux with microbubble emission. In periodic MEB, the bubble growth and collapse were repeated periodically in the channel. The heat fluxes in periodic MEB increased proportionally to the pressure frequency in the channel. The evaporation rates were roughly same values regardless of liquid subcooling and liquid velocity. The pressure frequency was considered as the number of liquid supply for one second.

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Dryout process appearing near critical heat flux for water boiling on an upward heating surface was investigated with conductance probes with tip diameter below 5μm. 2-D distribution of dryout void fraction was obtained by analyzing the dryout signals which were measured at 3〜5μm above the heating surface at 121 grid points in an area of 1×1[mm^2]. It was found that the dryout void fraction increased rapidly near critical heat flux and the dryout occurred in specific area of the heating surface. The liquid layer thicknesses were estimated based on the time from formation of vapor mass to start of dryout. and agreed well with the previously reported thicknesses which was determined from the height at which the vapor mass signal disappear.

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Boiling feature on a super-water-repellent(SWR) surface with a checkered coating pattern has been studied. Bubble nucleation begins at very low superheating and the overshoot of the boiling incipience is not observed. The stable film boiling occurs in very small superheating and there is no nucleate boiling region. The bubbles generated on the surface coalesce into a vapor film without departing from the surface.

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In this study, a multidiameter design according to the critical heat flux of each tube was proposed for a vertical tube boiler in order to improve its performance. Two types of multidiameter boiler were designed menufactured utilizing the calculation method for single diameter boiler. One is compact type and another is uniform heat flux type. An experiment was carried out in a wind-tunnel test bench using Fuluorinert (FC5312) as the working fluid. Experimental parameters were the velocity and the temperature of the hot air. The experimental results were compared between the multidiameter and the single diameter boiler. As a conclusion, the compact type shows larger thermal performance also larger pressure drop and smaller volume, while the uniform heat flux type shows the same thermal performance with the single diameter type and lower pressure drop. Further, it can be confirmed that the calculation method for the single diameter boiler can be utilized to the multidiameter one.

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The traditional method for drying of marine products is the warm air drying, which needs a long drying time and the quality of product is poor. Then we have developed the microwave irradiation drying under reduced pressure condition as a new drying method replaced by the warm air drying. The drying time was successfully shortened to about 1/20 of the warm air drying and low drying-temperature results in the good quality. The purpose of this study is an enhancement microwave drying by introducing external air. We found that the external air plays a role as carrier gas of water vapor and increase the drying rate.

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Drying process of porous media was analyzed by using two-dimensional numerical simulation. The results agree with the experimental characteristics reported previously. It is found that the diameter of the particle which composes porous media influences moisture distribution and drying time in falling rate period.

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Recently accurate results of Xe scattering from graphite have been obtained ; 1) the Xe angular distribution is peaked below the specular direction and becomes narrower as the incident energy increases, and 2) the direct scattering channel becomes dominant for high incident energies. Molecular scattering simulations have been employed to investigate these observations. We have employed the Brenner type intraplanar interaction potential and the Lennard-Jones potential for the interplaner interaction. Prom the numerical analyses, it becomes clear that the layered structure of graphite is responsible for the observed collision dynamics. The MD simulations reproduce the experiment for a wide range of initial conditions.

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Molecular dynamics simulation has been performed on pairs of solid walls and liquid films in between. As a shear is given to the liquid film by moving the solid walls, the Couette-like flow is generated in the liquid film and energy conversion occurs from the macroscopic flow to the thermal one, i.e., viscous heating in the macroscopic sense. In such a way, momentum transfer and thermal energy transfer are present simultaneously. At the solid-liquid interfaces, there exist large velocity and temperature jumps due to the large momentum and heat fluxes. It has been revealed in our present study that the characteristics of the energy and momentum transfer at the interfaces are greatly influenced by the crystal plane of the solid walls which contacts to the liquid film.

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Molecular dynamics simulations of heat transfer between carbon nanotubes in a bundle and between a carbon nanotube and surrounding Lennard-Jones fluid were performed. The Brenner potential with the simplified form is employed as the potential function between carbon and carbon within a nanotube. The heat transfer rate can be well expressed by employing the thermal boundary resistance (TBR). The value of thermal boundary resistance is compared for the bundle and nanotube-LJ cases.

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Raman scatterings from various SWNT samples were measured at a wide range of temperatures (from 4 K to about 1000 K). With increase in sample temperature, both the Raman shift and the intensity of G-band of SWNTs decreased, while the peak width increased. Through the comprehensive calibration, the temperature of SWNTs can be measured by using the temperature dependence of Raman shift and the intensity in the G-band. The temperature distribution of SWNTs induced by the Raman excitation laser was measured with this temperature measurement technique of SWNTs.

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A new rotational energy transfer model for polyatomic molecules in nonequilibrium rarefied gas flow is proposed in this paper. The model is based on dynamic molecular collision (DMC) model for diatomic molecules. The classical trajectory calculation (CTC) is conducted to simulate a large number of binary collision in various conditions. The pair potential is used for intermolecular one, and molecules are regarded as rigid rotors. The outcomes are separated into inelastic collisions and elastic ones. The inelastic collisios are analyzed statistically to represent the rotational energy transfer. We found a probability density function of energy transfer is expressed by exponential law as in the DMC model.

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The adsorption phenomena of H_2 on Pt (111) surface were simulated by the combination of accelerated Quantum Molecular Dynamics (QMD) method and classical Molecular Dynamics (MD) method. The Tight-Binding approximation and extended Huckel method are applied in order to decrease computational load. It was confirmed that the probability density function of electron obtained by this method is very consistent with the results of Density Functional Theory (DFT). About the binding energy and the structure of Pt surface, the results obtained by this method were also consistent with each other. On the viewpoint of energy conservation and temperature control, it was confirmed that this method can simulate the reaction phenomena on the catalyst well.

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We have carried out a molecular dynamics simulation for a mixture of an ice nucleus, supercooled water and a molecule of alanine tetra-peptide (A4) model. The A4 model has a herical structure which stands for a part of the antifreeze protein type I . This model has been set near the ice nucleus and had a slight fluctuating motion near the initial position. It is found that water molecules have some structures ,which are irrespective of the growth of ice crystals. This is confirmed from the angular distribution function of the water molecules in the near ice region.

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Our molecular dynamics investigation is the first one which describes the two-dimensional supercritical behavior of the ethanol monolayer spread at the air/water interface. Two-dimensional cluster analysis for the aggregation of adsorbed ethanol molecule in the monolayer shows that the state of monolayer transits from the non-percolating state to the percolating state across the percolation threshold, which is a typical behavior of supercritical fluid. The occurrence of a percolation transition is confirmed in terms of the universal quantities, the value of which only depends on the dimensionality of the system. The first example of the universal quantity is the critical space-occupation probability density ; the calculated value is about 0.5, which agrees with its universal value 0.44 in 2D system. Another example is the critical exponent for the non-percolating cluster number distribution ; the calculated value is 1.96, which agrees with its universal value 2.05 in 2D system. The cluster structure is also investigated.

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Spatial and temporal structure of electric double layer (EDL) in the vicinity of a glass wall of microchannel has been investigated by a novel nanoscale optical measurement technique using large-area evanescent wave light illumination and fluorescent dye. The fluorescent dye near the glass surface was excited by the evanescent wave, which was generated at an electrolyte-glass interface by total internal reflection of a laser beam with the characteristic penetration depth of 88 nm. As the concentration of fluorescent dye in the vicinity of the glass surface is dependent on the EDL thickness, calibration curves depicting the relationship between the fluorescent intensity and the EDL thickness were prepared to obtain the spatial and temporal distribution of EDL. It is concluded that the spatial distribution of EDL thickness is dependent on the molecular diffusion of positive ion in a buffer solution in the vicinity of the wall surface.

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Molecular dynamics simulations concerning a nano-scale liquid bridge between the solid walls are conducted. The 12-6 Lennard-Jones molecules corresponding to Argon are suspended between the platinum walls. The temperature of the wall is controlled by applying the phantom molecules. The temperature difference between the walls is applied after fully developing the system at a certain constant temperature for a long enough period. Net flow of the liquid-state molecules is observed in the bridge. The flow is almost two dimensional recirculating motion. The effect of the liquid bridge size and the temperature difference are discussed.

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Pressure in molecular dynamics system is obtained through forces acted on molecules in a region defining pressure by molecules outside of it However, in a very small system such asrequiredin nano scale technology, especially at fluid phase, many particles move across the boundary of the region. Therefore it is important how we should take averages with respect to time and volume to obtain the pressure. In this paper, three types of definition of pressure are calculated. As a result the relation between pressure and the system volume (the number of particles) is clarified in such a nano scale sm all system.

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In this study, stationary mutual diffusion of two kinds of liquid through a nano-porous thin film was simulated by means of two-dimensional molecular dynamics method. It was investigated whether the diameter of nanopore would affect diffusion phenomena. Lennard-Jones (L-J) potential was used for the two kinds of liquid and the thin film. As a result, the diameter of nanopore influences quantity of molar flow and concentration gradient, although it does not do diffusion velocity and molar flux.

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The disposal of captured fossil fuel CO_2 in the deep ocean, has been suggested as one means of ameliorating the global warming. We describe designed to study OACE (Ocean Abyssal Carbon Experiments). Observations from small scale (20 - 90 liters) CO_2 experiments conducted off the coast of California at 684 m depth and at 3942 m depth are discussed. In both experiments, when the seawater velocity was sufficiently strong, parcels of liquid CO_2 were torn off and transported away as discrete units by the turbulent water current. In the deep experiment, newly formed frazil hydrate was observed at the interface, occasionally including sediment particles. Hydrate furthermore collected and created a floating consolidated solid in the downstream end of the trough used to simulate the dented ocean floor in the 3942 m experiment, dissolving slowly from one day to the next. These observations have important implications for understanding of larger scale disposal at the seafloor.

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The depth where CO_2 can be stably stored is an important factor to select the storage site and has been thought 3000 m. However this depth was found to be not enough because the seawater above stored CO_2 is eventually saturated with CO_2 hydrate or CO_2 gas. Using newly obtained density data, the required depths where the density of CO_2 is equivalent to that of seawater saturated with CO_2 hydrate and CO_2 gas are evaluated as 3400 m and 3800 m, respectively. In order to prevent the so-called overflow phenomenon discovered by Brewer et al. of Monterey Bay Aquarium Research Institute, the latter depth is required for the stable CO_2 storage. The authors confirmed this conclusion through an in situ experiment conducted at 3941 m depth off California in October 2003.

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CO_2 sequestration in the ocean would be a highly advanced counter-measure to global warming if biological impact induced by CO_2 dissolution into ocean water is sufficiently small. Releasing liquid CO_2 droplets from a pipe towed by a ship is effective because of dilution due to the moving release point. If liquid CO_2 droplet sizes are controlled, dissolution into ocean water while rising up due to buoyancy, would take a long distance, which leads to vertical dilution. Dilution could be enhanced by a multi-nozzle array placed in the direction of ship width. Here we show that CO_2 dilution could be effectively further promoted by dispersing liquid CO_2 droplets horizontally by a turbulent wake formed by bodies placed at upper part of the multi-nozzle array. Turbulence formed at the downstream of the bodies could enlarge the width of rising liquid CO_2 droplets by turbulent mixing between sea water and droplets. We made a measurement of flow and statistical turbulent properties needed for numerical simulation behind a body. Based on the measured data, CO_2 enhanced dilution was simulated. Increase of partial CO_2 pressureand acidification are drastically decreased as compared with the case without dilution.

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The effectiveness of CO_2 injection in the sea off Japan was examined based on the calculation of the mean circulation in the Pacific Ocean. The diffusion calculation of CO_2 was carried out to predict the increasing of CO_2 concentration in the water body and to explore the effective CO_2 injection sea area near Japan, which suggests that CO_2 injection into the ocean abyss offshore of Japan on shifting the sea area by moving ship is more effective measure of CO_2 disposal than that of fixed sea area disposal.

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The interrelation between the liquid motion in the vicinity of a zigzag rising bubble and the interfacial motion of it in rest water has been investigated experimentally. The interfacial motion and surrounding liquid motion were measured by illumination imaging technique and PIV measurement, respectively. We discussed the asymmetric vorticity field of surrounding liquid and bubble shape deformation. As a result, it was confirmed that the curvature of outside at the inversion point was larger than that of inside, the vorticity of outside at the inversion point was also larger than that of inside, and these two parameters periodically fluctuate and have close correlation.

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The influence of buoyancy of an isolated air bubble is limited to the narrow region of about 3 times bubble radius from the center of the bubble. However, from the viewpoint of mass transfer, the interaction between the liquid-phase motion and the bubble interface motion is important to control the mass transfer across the interface. In the present study, we discuss the interaction between the interface motion of a bubble of about 3mm diameter and its surrounding liquid motion using LDA.

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This study was experimental investigation of the process of development of a bubble swarm and tries to clarify its relation to motion of liquid phase. The bubble swarm and its surrounding liquid motion were measured via high-speed CCD cameras and LDA system, respectively. As the bubble swarm progress, following bubbles are accelerated by the wake of preceding bubbles, and it caught up with preceding bubbles. Furthermore the members of the bubble swarm were dispersed. On the basis of the frequency analysis of the bubble motion in the bubble swarm and that of the liquid phase motion, a characteristic frequency has been found owing to the center of gravity motion of the bubbles.

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The dissolution of Carbon Dioxide (CO_2) drops covered with CO_2 hydrate films under a deep-sea condition has been investigated with a large high-pressure tank to evaluate environmental impacts of CO_2 ocean storage. Observation of CO_2 drops showed the dissolution of CO_2 drops was enhanced by disturbance around the drops, and pH measurement suggested dissolving CO_2 provided a CO_2-rich water layer above CO_2 drops. The drop diameter change was calculated by Ranz-Marshall's equation for a drop in flow with slow velocities and compared with the experimental result, which showed considerable dissolution rate would be provided by flow and increased with an increase in flow velocity.

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The thickness of CO_2 hydrate membrane formed at the interface between liquid CO_2 and water has not been measured directly yet since the pressure of hydrate forming region is over 4.5 MPa. The purpose of the present study is to evaluate its thickness by high-pressure experiments at 40〜50MPa, pressures equivalent to the deep ocean where CO_2 can stably be stored. We examined the method to measure its thickness using the laser light interfering method. As a result, its thickness was estimated to be the order of a few microns although it changes with the temperature.

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Sequestration of CO_2 to geological formations such as aquifers is considered to be one of possible strategies for the abatement of CO_2 emissions to the atmosphere. Because CO_2 rises upward in underground, one of options to ensure safety is to inject CO_2 into the layer under the seabed. In this case, it is essential to understand CO_2 leakage behavior that leads to whether CO_2 leaked gas could be sequestrated in seawater or not. CO_2 gasifies and leaks from the seabed with hydrate under the high-pressure and low-temperature condition. As injection behaviors of CO_2 gas with hydrate hasn't been researched, we observed injection behaviors of CO_2 gas with hydrate from single-hole nozzle including propagation velocity.

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CO_2 hydrate sequestration in sub-seabed sediments has been proposed as a novel option for greenhouse gas control, where liquid CO_2 is injected in seabed sediments, reacts with pore water and forms hydrates. The hydrate-filled sediments (hydrate sealing) are expected to serve as artificial cap rock, enabling a large volume liquid CO_2 to be stored in the underlying sediments. One of major concerns is whether hydrate formation can retard CO2 flow and prevent it from floating to the seabed. Model tests have been conducted to observe CO_2 flow behavior during hydrate formation when injected, at a constant rate, into an initially water-saturated porous glass model. The results shown that hydrate formation can efficiently retard the CO2 flow.

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In order to realize the sequestration of carbon dioxide (CO2) as a measure of global warming, we propose a new CO2 separation technology, GHS (Gas Hydrate Separation), which utilizes gas hydrate formation of CO2 gas mixture and separate CO2 efficiently and economically from reformed fuel gas. The objective of this research is to obtain engineering data of the GHS system including fundamental physical characteristics of CO2 hydrate and verify experimentally whether the system works (i) continuously and (ii) effectively, especially hydrate formation reacts at reasonable cost for industrial use.

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O_2/CO_2 combustion technique is suitable for CO_2 capture. A cryogenic air separation using single rectification column was proposed for O_2 production. In the present paper, feasibility study of simplified natural gas combined cycle, NGCC, utilized CO_2 recovery system was deliberated. Power plant consists of three units: ASU (Air Separation Unit), NGCC, and captured-gas compression unit. These units are built on present technologies of conventional plants. Simulation software, HYSYS.Process, was used to simulate and calculate the net thermal efficiency. We have considered two cases; case 1 is 200-300MW output gas turbine, and case 2 is 50MW output gas turbine. As a result, thermal efficiencies achieve 45.4% in case 1 and 43.3% in case 2. In addition, cases have possibilities to increase thermal efficiencies by using of regenerative technique.

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We developed a new model for the dissociation rate of methane hydrate (MH) at its surface. It was incorporated to our numerical flow simulation code, which features a finite volume method, unstructured mesh and very thin layer (VTL) cells at the surface. The VTL is aimed to predict the mass transfer of methane for high Schmidt number. For solving the unknown intrinsic dissociation rates in our model, we conducted the laboratory experiments of MH decomposition and obtained the bulk flux of methane into water. By applying the numerical code, the intrinsic dissociation rates were determined under various flow conditions of ambient water, such as pressure, temperature, and flow rate.

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In this paper we present an experiment on the behavior of COz hydrate formation in sand layer. The equilibrium condition and growth kinetics of CO_2 hydrate formation were examined by using a small-scale pressure cell filled with porous media in unsaturated condition of water and gas. The mechanism of CO_2 hydrate formation in porous media and the rate of crystal growth were clarified on the basis of the method of in-situ observation and measurement.

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This paper describes experimental research on two-phase flow of supercritical CO_2 and water in a porous medium. We used a magnetic resonance imaging (MRI) technique to directly visualize the distribution of supercritical CO_2 injected into a packed bed of glass beads containing water. In-situ saturation distributions were successfully visualized under the temperature and pressure conditions corresponding to the aquifers at the depth of about 800m. A new coreflood interpretation method proposed by Goodfield et al. was applied to in-situ saturation data to evaluate two-phase flows in porous media directly. We calculate darcy velocity of two-phase flows of super critical CO_2 and water in porous media.

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Carbon dioxide is considered to be the greenhouse gas which most contributes to global warming on the earth. Sequestration of CO_2 to geological formations such as aquifers is considered as one of the possible options for the abatement of CO_2 emission to the atmosphere. One of the crucial problems about geological sequestration is the leakage of CO2 from reservoirs. This paper describes numerical research on the mechanism of leakage from the reservoir through the cap-rock. Not absolute permeability of cap-rock but the difference of capillary pressure characteristics between cap-rock and reservoir governs the saturation of sequestered CO_2.

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The condensate liquid movement by applying bulk temperature gradient on the heat transfer surface in solutal Marangoni condensation was investigated, considering the application to the heat transfer devices. In solutal Marangoni condensation process, the removal of condensate on the heat transfer surface is important to keep good heat transfer. It may be useful for the heat transfer device in which the liquid movement occurs without external forces such as gravity, vapor shear force and so forth. As a result of the experiment using water - ethanol vapor mixture, the movement of the droplets from low temperature-side to high temperature-side could be observed on the heat transfer surface arranged horizontally. Furthermore, the relation between the velocity of drop movement and the gradient of surface tension was studied for different concentration.

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