Due to very strong compressibility, a fluid near critical point is compressed by its own weight under Ig. Being free from the gravity effect, microgravity conditions are necessary for conducting an experiment on near critical fluid behavior. We study heat transfer experimentally and numerically in a supercritical CO_2 under microgravity. We succeed that numerical analysis has capture the thermal diffusion layer by experiment according to take the peculiarity of the thermal properties in near critical point into consideration.

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It was considered that space environment was completely weightless. Inside spacecrafts, such as the Space Shuttle and the International Space Station, however, the existence of residual acceleration has been reported. The acceleration is called "g-jitter." In a lot of experiments carried out in space, the adverse influence of the g-jitter on their results has been found out. To extend our understanding on the g-jitter, a research group has been organized. Here, some results from researches on the g-jitter are briefly introduced.

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Thermocapillary-driven convection in a half-zone liquid bridge has been extensively examined hitherto. The dynamic free-surface deformation was often observed in the experiments. Influence of the deformation upon the flow in the bridge, however, have not been understood yet. The three-dimensional thermocapillary convection has been simulated numerically with taking the dynamic deformation of the free surface into account. The shape of the liquid bridge was determined by the stress balance over the surface.

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In this study, a novel damping system for microgravity experiments using an airplane has been proposed. This system is constructed of the Non-Linear Passive Damper (NLPD) and the shock absorber, and it does not consume any electric power. This system has been developed for making non-forced field. Because many experiment results and numerical simulations under the microgravity condition were reported that the residual acceleration and g-jitter influence the experiment using the fluid. In this research, crystal growth experiment was performed to obtain the observation about the influence of g-jitter. The results show that the effect of g-jitter was appeared in the crystal growth rate.

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Inverse solutions for one- and two-dimensional heat conduction has been explicitly derived using Laplace transform to estimate surface temperature and heat flux. These inverse solutions can be widely applied to transient heat transfer problems, for which it is usually difficult to calculate the surface condition form a measurement of temperatures in a solid. A few examples of the applications of inverse solutions are presented.

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Considering the optical characteristics of silicone wafer, the transient radiative heat transfer analyses based on gray assumption were applied to rapid-heating process. The results show that regularity and transparency of wafer surface give a slight reduction in the wafer temperature distribution in one side.

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Coke is produced by heating upto 1,000℃ for 20 hours. So heating program and dry quenching (CDQ) systems are introduced to reduce heating time. The thermal properties and heat transfer mechanism are clarified for the rational operation. This paper describes situations of measurements of the thermal conductivity during carbonization process, numerical analysis of fissure formation in the coke lump, development of thermal pyrolysis, heat transfer mechanism of CDQ and raceway of blast furnace.

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The objective of the present study is to investigate the advanced thermal energy storage/transport system with ice water slurry. Thermal energy storage systems for air conditioning has been developed actively for the purpose of saving energy and reducing the peak electrical demand in the daytime during summer. In particular, a great deal of attention has been paid to the thermal energy storage system with ice water slurry since it would be beneficial to be able to utilize the large latent heat of melting ice. It is required to clarify fundamental making/transport/melting mechanism of ice water slurry for the systems, so this paper deals with a dynamic ice making characteristics using flowing supercooled water solutions, pressure drop of flowing ice water slurry in a pipe, and melting heat transfer of ice water slurry in a heat exchanger.

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Hydrogen, which does not generate CO_2 by combustion, is considered to be an important (clean) energy source in near future. In the middle of 21st century, hydrogen energy society may be realized. In this study, several distributed hydrogen energy systems, which use hydrogen produced by water electrolysis, are dealt, and the energy costs for each system are evaluated. As a result, the energy cost using Brown's gas is greater than that of using the town gas in the case of present cost of equipment. However, in the case of 50% of the cost of equipment and cost of town gas of 100 yen/m^3, the case of Brown's gas is nearly equal to the case using town gas.

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Recent trends of biomass energy were briefly reviewed, and the potential of biomass energy was discussed from view points of renewability, C02 reduction effect and applicable mass of resources. Biomass ethanol was considered to be the most attractive energy because of its well preservation and wide applicability to motor vehicles, and the technical problems in the production of fuel ethanol were also discussed. For the practical use of fuel ethanol, the new production system was proposed and the energy requirements in the concentration of a fermented ethanol to a dehydrated ethanol were studied. The results showed that the heat integrated distillation column (HIDiC) to be developed had a large potential in energy saving. It was confirmed that the energy requirement of the HIDiC was less than 55% of a conventional distillation column, and that the dehydration by membrane process also needed less than 30% of the energy required in the conventional azeotrope distillation process.

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Hydrogen that has multilateral functions as for energy performance is a possible energy carrier for the future. This paper deals with the development of a horizontally integrated energy system, which consists of a reversible fuel cell stack unitizing both functions of electrolysis and electric power generation and a metal hydride device utilizing an energy storage function. The proposed energy system here is sure to become a fruitful technical option for the load-leveling of electricity in commercial building facilities. Moreover, it is possible for this energy system to innovate the energy performance such as not only to eliminate the mismatch between energy supply and demand but also to improve the robustness for any energy shortage in multilateral and decentralized users.

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A membrane reformer equipped with palladium membranes has been developed. Palladium alloy, which allows only hydrogen to pass through, is fabricated into membranes and used in the reformer for direct production of high-purity hydrogen from city gas. The operation test of the membrane reformer have demonstrated that the hydrogen production rate of 14 Nm^3h^<-1> as had been designed, the product hydrogen purity of over 99.999%, and stable unmanned continuous operation of over 1,000 hours. These results have led us to believe that the membrane reformer can suitably be applied to fuel processor systems for polymer electrolyte fuel cells (PEFC) and hydrogen refueling stations for fuel cell electric vehicles (FCEV).

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A hydrogen storage system using hydrogen-absorbing alloy bed has the advantage of safer operation than other system using a high pressure. However, an exothermic chemical reaction during hydrogen absorption of the alloy depends on its temperature as well as hydrogen pressure. So an effective heat exchange between a coolant and the alloy bed having very poor heat conductivity is important to enhance the chemical reaction. As the results, heat conduction in the bed, is strongly coupled with the absorption or desorption process. This study has just started to develop and evaluate enhancement of the poor heat conduction in the bed. Experimental results during hydrogen absorption using LaNi_5 are shown and compared with simulation results.

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At first, in order to measure the effective thermal conductivity of MH bed, we proposed simple unsteady state method. In our measurement, the effective thermal conductivity of MH alloy bed is extremely low (under 1 W/m ・ K). And, the effective thermal conductivity of MH-2 bed is higher than that of MH-1 bed. Next, an attempt by mixing the carbon fiber into the MH bed is discussed, to enhance the heat transfer performance. The experimental parameters of heat transfer enhancement are the length and mass fraction of carbon fiber. As the best result of MH bed, the effective thermal conductivity of mixing 2-3 wt.% carbon fiber is three-four times larger than that of the pure MH bed.

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Rapidly solidified LaNi_5 alloy wires were prepared by the In-Rotating-Water Spinning Process. The spinnability and the effects of spinning conditions on the shape of prepared wire were examined using a quartz nozzle of 0.5mm diameter. About 30cm long straight wires with diameters ranging from 0.15 to 0.5mm were produced at a relatively high melt temperature of around 1500℃. However, the hydrogen absorbing capacity of the produced wires decreased by about 30% compared to ingot alloy. It was inferred that this was probably due to the reaction between the quartz nozzle and LaNi_5 during the melting process.

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Self diffusion coefficients of water in polymer electrolyte fuel cell membrane(PEM) were measured using pulsed field gradient spin echo NMR measurement. Two types of PEM sample were investigated at various water content. It is shown that measured self-diffusion coefficients increased with water content in the membane, although no distinct difference was observed among two types of PEM. Furthermore, it is demonstrated that NMR imaging technique can be applied to probe water behaviors in PEM assembled in fuel cell under operation. It is shown that PEM gradually dried after the fuel cell began to be operated, resulting in decreasing output current.

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Molecular simulation, such as molecular dynamics and Monte Carlo techniques, is now widely used in research of various fields of engineering. The simulation has two essential roles, i.e., to investigate elementary processes in detail at molecular levels, and to extract information or parameters for bridging microand macro-scale modelings. In this paper, I present several examples of our recent study on thermo-fluid phenomena with molecular simulation. (1) Ion-induced nucleation in supersaturated water vapor: the sign effect can be understood only at the molecular level. (2) Dynamics of a collapsing bubble in liquid: during the shrink of the bubble, the inside vapor is compressed. The condensation and evaporation under extremely non-equilibrium conditions is relevant and is investigated with molecular simulation. (3) Flow around a rising bubble: the slip boundary exists on the bubble surface when adsorption is negligible. Relation between the adsorption-desorption dynamics and the fluid dynamic boundary conditions is the main target. (4) Shock wave propagation in liquid: shock wave is generated and propagated from highly compressed liquid region. For shock wave profiles, there is a quantitative disagreement between molecular simulation and numerical fluid dynamics.

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The gas-wall interaction is investigated for the thermal problem between two walls whose temperature is different each other. The wall consists of platinum molecules, and the gas is taken to be argon. It is found that the distribution function of the reflected molecule is close to that of Maxwellian type. The Maxwell type boundary condition describes well the distribution function of the reflected molecule if a proper accommodation coefficient is taken.

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Scattering properties of gas atoms interacting with a metal surface are calculated using a solid surface model including Phantom Particles followed by the Langevin equation. The Phantom Particle represents the statistical bulk characteristics of a metal solid, and it is applied to a gas-surface interaction for Ar-Pt(111) system. While the flux distributions, the TOP spectrum, and average energy of gas atoms scattered at the specular angle are compared with those of molecular beam experiments, the trapping probability and energy exchange rates are calculated to discuss the fundamental mechanism for gas-surface interaction.

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The supersonic expansion of a heavy gas and a light gas may result in a velocity slip and a temperature difference between light and heavy species. The purpose of this paper is to study the influence of these phenomena on the relaxation of internal degrees of freedom in the free jet expansion of N_2-He mixture. We obtain the rotational temperature distribution of a supersonic free jet experimentally by electron beam fluorescence method, and compare it with the result of the numerical simulation by DSMC method.

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In recent years, OPMS (Optical Pressure Measurement System) using PSP ( Pressure Sensitive Paint) has been developed for measuring pressure distributions on wind tunnel models. To apply the PSP to measurement of pressure distribution on a solid surface settled in the rarefied gas flows, we had examined the fundamental features, such as pressure sensitivity and luminescence intensity. In this study, PtTFPP/poly(TMSP) is selected as a PSP and applied to investigation of pressure distribution on a solid-surface impinging a rarefied gas jet by PSP.

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The flow in a plasma reactor has effects on plasma etching. It is important for the optimum design of a plasma reactor to know the gas flow in the plasma reactor. We examined the three-demensional rarefied flows in the reactor using DSMC method.Based on these DSMC data, the minimal height of the reactor, for which the gas fkow probably has no effect on etch rate distribution, is determined.

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The substrate biasing is a standard technique to control the energy of ions incident on a wafer. The effect of substrate biasing on dc discharge field is examined using the exact solution of the Poisson equation. It is found that the effect of biasing is not limited to the region near the substrate but biasing influences the whole discharge field.

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CO_2 management technology is one of the most important issues for the global environment. This paper describes the feasibility experiment that CO_2 can be reformed by direct conversion into fuel-like species with the aid of plasma reactions. Here, (CO_2+H_2+Ar) is discharged into an expansion chamber rising a plasma reaction furnace and the chemical species produced by plasma direct mass conversion are detected by a combined time-of-flight and mass spectrometer technique. As the result, fuel-like species such as CO, CH_4, and CH_3OH are gained. And the paper describes quantum chemical analysis using an ab initio Molecular Orbital method to know the microscopic mechanisms of plasma-assisted mass-conversion from (CO_2+H_2O) into CH_3OH. As a result, we have made clear great contribution of H_2O in the process.

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The formation and dissolution mechanism of methane hydrate is investigated at a molecular level using molecular dynamics method. The key of whether or not methane hydrate can be formed is the stability of the hydrate structure. Computer simulation results show that very stable methane hydrate type I can be formed below 275K. The stability of the hydrates increasingly degrades logarithmically as a power function above 275K up to 300K.

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Advanced clathrate hydrate slurry (CHS) has been developed using tetra-n-butyl-ammonium bromide by NKK. The CHS has latent heat over the temperature range of 5〜12℃ which are the common temperature range for the conventional water-cooling air-conditioning system. The CHS has advantages as a cold transportaion medium compared with water due to a greater cooling capacity. The characteristics of the CHS obtained by a series of experiments, operation results of a CHS system under an actual cooling load, and results of feasibility study are reported in this paper.

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Supercritical Water Oxidation (SCWO) employs water which exceeds supercritical conditions (374℃ at 22MPa). This method utilizes the strong reactive solvent characteristics of supercritical water and can completely decompose organic materials in supercritical water. As a hazardous and refractory chemicals, decomposition of PCBs by SCWO was demonstrated using the continuous reactor with pressure balancing. This reactor has been successfully operated to decompose both PCBs and dioxins completely under the conditions of 630℃ and 23.5MPa.

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Experimental and numerical analysis of methanol steam reforming for fuel cell has been done. The reforming catalyst was supported by metal honeycomb to decrease the heat capacity. Conversion performances were improved by segmenting the catalyst into several blocks due to the enhancement of mixture of gases and heat transfer at the front edges of the segmenting catalyst. Numerical simulation model for methanol steam reforming catalyst was developed by changing chemical reactions in the model for exhaust catalyst of internal combustion engine and using a smaller mass transfer coefficient for methanol steam reforming.

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This paper describes a consideration on coal gasification in the blast furnace for combined with power generation and hot metal production. This system has a lot of benefit for large capacity and high efficiency power generation and great reduction of coke by using large amount of fuel coal for injection into the blast furnace. Consideration on gasification deals a process simulation of reaction and heat transfer takes place in the blast furnace to predict the performance prior to actual test at commercial plant, and over views the total performance of the system.

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A feasible experiment and quantum calculation are performed on plasma direct mass conversion of CO2 into fuel-like species such as CO, CH4, CH3OH, etc. Test mixture gases of (CO2+H2+Ar) and (CO2+H2O+Ar) are discharged into a evacuated chamber in which a plasma reaction furnace is equipped, and directly mass conversed species produced by the plasma are detected by a combined time -of-flight and mass spectrometer technique. We confirm the mass conversion of the mixtures into CO, CH4 and CH3OH with fairly good yields. The molecular orbital method is also found to be a attractive to know the microscopic mechanism, chemical potentials,

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The problem of present study and the development are described on simulation of combustion characteristics by l)large eddy simulation and 2)emissivity based on non-gray gas model of CO_2, H_2O and methane fuel in the case of high air temperature combustion process, and sub-models such as 3)ash softening and adhesion model to the wall in the pulverized coal combustion, 4)soot formation and agglomeration models, and 5)the simplified reaction model for the NOx formation rate.

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The use of waste to energy has attracted interest as an important way to the effective utilization of not used domestic energy resources. 4.2t/h steam generation capacity demonstration thermal power plant using RDF has been operated from Oct. 1997 until today more than 13,200hrs at Wakamatsu Coal Utilization Research Center, Electric Power Development Co.,LTD, supported by the METI (Ministry of Economy, Trade and Industry) Agency of Natural Resources and Energy. This paper is described about outline of the test facility and classification of the used RDF, and history of the development and operation results of the Wakamatsu RDF thermal power plant.

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An innovative small-scale gasification system for solid wastes is proposed which is known as STAR-MEET system. In this system, a fixed-bed pyrolyzer combined with a high temperature reformer using high temperature steam/air mixture is employed. From the experimental results using rubber chips as a fuel, it has been found that injection of high temperature air into the pyrolyzer significantly increases the heating value of the pyrolysis gas. It has been also demonstrated that injection of high temperature steam/air mixture into the pyrolysis gas effectively decomposes tar and soot components in the pyrolysis gas into CO and H_2, and almost dust and tar free clean reformed gas can be generated. This gasification system generates low BTU gas from solid wastes. Thus power generation experiments using a small spark ignition engine were done employing low BTU gas as a fuel. Compared with natural gas driven, low BTU gas driven engine shows similar thermal efficiency while significantly low NOx and hydrocarbon emissions.

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This paper deals with the molecular mechanism of muscle contraction. The changes of thermodynamic parameters of motor protein myosin during ATP hydrolysis reaction have been examined based on hydration study. The changes of protein hydration were measured by using microwave dielectric method. The hydrophobic hydration was also examined with solutions of hydrophobic amino acids and found to be proportional to the accessible surface area of hydrophobic moieties. It is consistent with the reported values of heat capacity change and entropy change of transfer from hydrocarbon to water. By this study the. ATP hydrolysis in myosin motor domain SI was successfully explained by conjugation between the interaction of hydrophobic moieties at the protein surface and the enthalpy increasing reaction such as hydrogen bond breaking inside protein. This mechanismof △H-△S conpensation can be applied to develop a linear motor system by a hydrophobicity gradient force. The enginerring model is also discussed.

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The permeability of PC-3 cells to water was measured by using a perfusion technique. Permeability was lower for endosmotic flow during shrinking than for exosmotic flow during swelling by about 30%. When cells swelled in a hypotonic solution, more than half of the cell population showed unusual behavior that could not be characterized by the classic analysis for osmotic volume change. The rest behaved as an osmometer while the final volume in the hypotonic solution with the osmolarity of about half of isotonic was slightly lower than the linear correlation between the cell volume and the reciprocal of osmolarity that was determined in the hypertonic solution.

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Behavior of ice crystals and cells in the biological tissues during the slow-warming after rapid-cooling was investigated microscopically on real time using a confocal laser scanning microscope with a fluorescent dye. Attention was paid on the recrystallization of intracellular ice crystals. The recrystallization could increase the mechanical damage of the tissues due to ice crystals. Size and number of the ice crystals were measured from the image-data of ice crystals. The size of ice crystals was statistically analyzed. Frequency, average, standard deviation, sum of amount of ice crystals, etc. were made clear in time-series during the slow-warming.

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About various kinds of water solution and its solid (frozen water solution), their dielectric absorption properties are measured with an impedance analyzer in the frequency region from about 10M to about 200MHz. It was found that some kinds of water solution showed unique phenomena that is 'dielectric loss factor of the solid is larger than the liquid within limited frequency range'. The component in the water solution is succharines (sucrose and so on) or polyhydric alcohol and its polymer (polyethylen glycol and so on). The unique phenomena showed that it was possible to thaw frozen substance made up of water with dielectric heating uniformly.

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It is known that the growth mode and patterns of microorganic colonies are altered depending on the growth conditions such as the nutrient concentration and the viscosity of the culture medium. The purpose of this study is to develop a simple numerical model of microorganic colonies' growth, which mimics the actual growth mode and patterns. The control parameters are the nutrient concentration, the critical nutrient concentration for the cell division and the diffusion coefficient of the nutrient molecules which is related to the viscosity of the culture medium. The model realises the actual growth mode and patterns very well.

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This paper deals with the effect of vapor flow on heat transfer in bread during baking. Temperature, pressure and water content distributions were measured within a dough during the baking process, and enthalpy flow due to vapor flow estimated from the measured results was compared to the conductive heat transfer within the dough. The results showed that; (1) the vapor flow markedly affects the temperature distribution in the dough during baking process, (2) the enthalpy flow due to vapor flow is in the same order of magnitude as the conductive heat transfer, but the direction is opposite to each other, and (3) in the eary stage of the baking process, the outward vapor flow is weakend due to evaporation occuring in the surface region of the dough, and the convective heat transfer within the dough might be enhanced by the vapor flow during the stage.

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The warmed-air drying process of laver was observed experimentally and transient behaviors of moisture content, temperature and survival ratio were examined. The process consists of two characteristic periods, i.e. a constant rate period and a falling rate period. At a critical moisture content being a changing point from the constant rate period to the falling rate period, the temperature of laver cellular starts increasing rapidly. The experimental observation indicates that the temperature rise is a dominant factor to determine the survival ratio. Based on the results a best method for drying is presented.

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We have developed a coupled system of a human thermal model and .CFD to predict physiological response and indoor thermal environment simultaneously by solving energy equations regarding the human.body and indoor environment as one thermal problem. This coupled system takes into consideration convective and radiative heat transfer and moisture mass transfer at the skin surface and simulates the heat exchange between the thermoregulated human body and its surroundings. The coupled system was applied to a uniform thermal environment at ambient temperature of 22 and 28℃. The heat transfer and moisture mass transfer rates from the human body and the surrounding environment were predicted using the model based on thermoregulatory response in each condition.

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Experimental and calculated investigation on heat transfer in a low temperature sauna was made. Low temperature sauna was usually heated up by a radiation panel heater at the ceiling to 50 degree C. In order to examine how heat transfers from the radiation heater to a human body in a sauna room, temperature and velocity distribution air were examined by the experiment and calculation of indoor air flow. It was found that heat flowed from the radiation heater to the human body mainly through air convection and wall radiation, not direct radiation from the heater.

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A non-contact method was used to measure the thermal conductivity and thermal diffusivity of biological tissues. The method is based on the fact that the time variation of the heated surface temperature depends mainly on the thermal properties of the material when its surface is heated locally. A CO_2 laser and an infrared thermometer were used for heating and surface temperature measurements. The measured temperature variation was compared with that obtained numerically in advance, then the thermal conductivity and thermal diffusivity were evaluated simultaneously. Uncertainty analysis showed that the present method could measure the thermal conductivity and thermal diffusivity of biological tissues within uncertainties of 5 and 10 %, respectively.

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This paper deals with the integrated energy service system for an specific area that is supposed to deliver electric and thermal energy in an integrated manner for the purpose of reducing cost, primary energy consumption and CO2 emission. A brief description of the multi-objective programming model that consists of three sub-models is given. First sub-model is to determine the optimal share of energy system options including District Heating & Cooling (DHC) system and distributed power generation systems. The second is to determine the optimal piping network for the DHC system and the third is to determine an optimal electric distribution network. Numerical results obtained for a specific area will be shown.

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The authors has shown general characteristics of cogeneration system (CHP) on economic benefit and carbon dioxide reduction by simplifying the conditions without losing its basic features. The previous research indicated large economic improvement by networking heat supply among different building types. The present paper analyses the optimum distribution of building types as a CHP network, together with pipeline roots. Heat loss and necessary pipeline diameter, which affects cost significantly, are taken into the analysis. The result shows optimum size of the network and ratios of floor areas of building types as an example.

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This paper presents a study of the performance of the solar thermal power generation system that has been working on the Inverted Brayton cycle. The temperature rise of the HTS (Heat Transfer Salt) is measured by experimentally. The HTS used as heat storage material in heated by focusing and solar energy through the convex lens. The heat storage and heat transport characteristics are investigated by using the experimental model heated by electric heater. It is shown that if the high temperature HTS of more than 300 degree centigrade was realized, this solar thermal power generation system has revealed more than 30% of thermal efficiency.

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