This paper describes a method for perforating fish egg (Medaka) membrane efficiently by using a rectangular electric pulse applied between the plate electrode and the hollow needle electrode. Minimum required pulse strength to perforate egg membrane (chorion and yolk membrane) was measured under the various pulse lengths and concentrations of supporting liquid. The results ahowed that the minimum required pulse strength was decreased with increasing pulse length and electric conductivity of the solution. In addition, egg membreanes in the hypertonic solution (〜130mOsm/kg) could not be perforated because of their severe deformation. It can be concluded that appropriate high electric conductivity avoiding egg's doformation might be required to perforate fish membrane with low pulse strength.

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Interactions among water, ice, and solute in frozen organic solutions play an important role in stability during cryopreservation. The aim of this study was therefore to investigate microscopic distribution of water, ice, and organic matters after freezing at different conditions. Trehalose and albumin solutions filled in a microchannel were placed on a directional solidification stage combined with a laser raman microscope. The directional solidification stage maintained one end of the channel at -20℃ and the other end at +20℃ so that the solution could be solidified from one end to the other. The spectra of C-H and O-H bonds were respectively obtained by scanning the frozen solution with the laser raman microscope. organic matters or CH-rich regions were finely dispersed at highly supercooled areas because of the higher solidification speed. They however condensed as visible spots at lower supercooled areas since the solutes were rejected during freezing and entrapped between ices. Near the ice front, the organic matters were almost completely rejected from the ice. The results demonstrated that raman imaging is a powerful tool to visualize the distribution of organic matters depending on the degree of supercooling and thus the solidification speed.

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In this study, a numcrical simulation on the freezing and thawing processes is developed to evaluate the solution effects on the quality of frozen-fish tissues. We use a simulation model containing muscle fibers to express the micro-scale heat and mass transport phenomena inside the tissues. The calculation can show the temperature increase due to the release of latent heat at the time estimated by the IIF theory, and the cell shrinkage behavior caused by the vapor pressure difference in the unfrozen-cell region is presented. In the thawing process, we cannot confirm the re-crystallization from the present calculation.

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Numerical calculations were carried out to reveal both velocity and oxygen concentration fields around a red blood cell. It is well-known that the cell changes its shape and orientation, as it flows in a capillary. The mass and momentum conservation equations for the blood plasma were solved along with the oxygen transport equation. The effects of the shape of the red blood cell on the velocity and oxygen concentration fields are numerically investigated using a numerical model consisting of the blood plasma, red cell and capillary wall.

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An environmentally friendly and low-friction bearing for applications such as tidal power or streamflow generation is proposed using biomimetic technologies. A biomimetic bearing was successfully developed using an ultra-high molecular weight polyethylene (UHMWPE) or a hydrated material, polyvinyl formal (PVF), which mimics articular cartilage in a natural synovial joint. A non-Newtonian fluid, polyethylene glycol (PEG) dissolved in distilled water, was used as a lubricant, and the biomimetic bearing exhibited excellent frictional properties to reduce the mechanical loss.

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Comfort predictions based on biological information were performed in office environments. Subjects worked in two environments; One is the office with a conventional air conditioning, and the other is with the radiational conditioning functioning all day and night. Activation of parasympathetic nerve and deactivation of sympathetic nerve, in which the subjects might feel a comfortable environment and expect improvement of intellectual productivity, were recorded when the subjects worked in the radiational conditioning. The activation of sympathetic nerve or parasympathetic nerve was estimated through analysis of electrocardiogram. This non-invasive method has a beneficial effect on the estimation of comfortable environment.

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To obtain cooling data for high power electronic devices such as inverter in electric vehicle, subcooled pool boiling has been performed for binary mixtures of ethylene-glycol and water under atmospheric condition. Volume concentration of ethylene-glycol is 30% and 50%. Microbubble emission boiling is observed at above 40K of liquid subcooling and the heat flux increases higher than CHF. The maximum heat flux is 350W/cm^2 at about 200℃. It satisfies the requirements of maximum cooling heat flux of 300W/cm^2 for a power inverter of future electric vehicle. However, the heat flux and heat transfer coefficient are considerably lower than those of water.

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A parametric experiment of saturated pool boiling on a horizontal heated wire was performed, by changing parameters such as test liquid, wire material and system pressure, to make clear the dependence of critical heat flux on wire diameter. Over 1000 data are accumulated for the slender wire with various diameter and correlated in dimensionless form like Sun-Lienhard' s. It is found that the CHF data scatter is very large even if the test condition is kept to be the same. In the present report, the reasons of the data scatter is experimentally studied and discussed.

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Experiments were carried out to observe boiling behaviors of water on a vertical surface at pressures from 0.35MPa to 5MPa. The growth curves of the primary bubbles are well described by the t^<1/2> variation over the whole range of pressures. The growth rates of primary bubbles are proportional to the square root of the Jakob number, and agree with the correlation by Labuntsov with the arbitrary constant β=3. The nucleation site densities measured up to 5MPa increased in proportion to about the 1.5th power of the pressure under equivalent heat flux conditions. The dependence of the nucleation site densities on the heat flux is very similar to the results obtained near atmospheric pressure where the nucleation site density is proportional to the 1.5th power of the heat flux

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Compared to single-phase flow, nucleate boiling has high heat transfer coefficient and is widely used in heat exchangers, boilers and BWR, etc. The nucleate boiling has been studied extensively but its heat transfer mechanism is still unknown. Recently, JAEA has developed a technology for the measurements of the surface heat flux and surface temperature distributions. The technology solved inverse heat conduction problem to get the surface heat flux and surface temperature distributions, with using a measured inside wall temperature distribution data from self-developed high sensitive temperature sensors. The temperature sensors are allocated in high density (utmost 6 points in 1 mm), at a depth several micro meters beneath the heated surface. In this paper, with using the developed technology, we measured the surface heat Flux and surface temperature distributions under a nucleate pool boiling bubble at both atmospheric pressure and a lower pressure. Image information of boiling bubble was recorded with a high speed camera synchronized with the temperature measurements. To control the position of boiling bubble, we mirror processed the heated surface and formed a nucleus at the center of the surface. Temperature sensors are allocated beside the nucleus, in a density of upmost 6 points per 1mm and at a depth about 1.4μm beneath the surface. Based on the experimental data, we examined boiling heat transfer models. In the present experimental conditions, surface heat flux distribution in the boiling process shows contact line heat transfer model is correct.

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For improvement of reliability, the air cooling heat exchanger of natural convection type has been developed. Since the heat transfer coefficient was small in the case of natural convection flow, finned cylinders set was studied for increasing heat exchange area. However, the composition of finned cylinders set which has the maximum heat transfer coefficient is unknown, so heat exchanger design can't be performed. Then, the maximum heat transfer coefficient of finned cylinders set is investigated by examination with stuck and finned cylinders set. A result is that, when a vertical direction pitch is 5 times of fin diameter, a heat transfer coefficient is max, because of the effect between the stuck and the decreasing temperature of natural convection flow with expanding vertical pitch. As compared with 1 pipe in open space, it is conformed that finned cylinders set mean heat transfer coefficient increased by 1.6 times.

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Either top or bottom wall temperature of an infinite horizontal fluid layer is time-dependently and sinusoidally oscillated with the constant average temperature on the opposing horizontal wall. This is the system with no temperature difference between the top and bottom walls in a time-averaged sense, as studied by Kalabin et al. for a square channel. The fluid is Newtonian and Boussinesq approximation is made. The fluid layer of height 1 versus the horizontal width 4 is adopted and numerical computation is carried out. The time-averaged heat flux is always positive, i.e., upward, even if the time-averaged temperature difference is zero between the top and bottom walls. This holds even if the oscillating temperature is on either the top or bottom walls.

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Heat transfer and fluid flow on the heated disc during the laminar forced convection have been investigated experimentally. The gas flow in the acrylic cylindrical pipe was laminated by the plastic honeycomb and packed bed of polystyrene. The heater was set centrally apart from the exit of the pipe. When the distance between the exit of the pipe and the heater, h, was 20mm, there was the critical line for the vortex due to the natural convection on the Re-Gr map. On the other hand, for h=mm, there was no vortex in there experimental conditions. By comparing the gas flow patterns and temperature distribution, it suggested the fluid body with high temperature was traveling along the radius direction.

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This paper describes the heat transfer enhancement mechanism on the forced convection by spraying a slight quantity of mist in a channel of a backward-facing step flow. The mist reduces temperature of a main flow by displacement of the latent heat accompanying evaporation. In this research, about the above-mentioned phenomenon was done by both of the experiment and the computer simulation. And, we compared those results and considered that about the relation of the behavior and evaporation process of the mist. Finally, about the mechanism of the heat transfer enhancement by spraying a slight quantity of mist in a recirculation region was discussed.

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The adjoint-based shape optimization is applied to a parallel channel with oblique waves, which was found to be quite promising for enhancing heat transfer in single-phase laminar flow with relatively small pressure penalty. It is found that the optimized wall geometry further increases the heat transfer rate by around 8% from that achieved by the existing oblique wave, while the pressure loss is kept unchanged. Meanwhile, the same optimization procedure is also applied to an initially random surface. The resultant optimized surface exhibits a property of oblique waves. This implies that an oblique wavy surface is optimal for achieving dissimilar heat transfer enhancement while suppressing the pressure loss.

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This study is on the numerical computation of the transport phenomena in the salinity-gradient solar pond. The pond consists of three layers of water, 10 wt% saltwater, and the intermediate region. In this computation, the dependence of the temperature and the concentration on the properties were considered. As the result, the numerical simulations of the diffusion process of mass and energy suggest the heat accumulation in the saltwater. Further, the simulation considering fluid flow was carried out. According to this calculation, it was found that the intermediate insulating layer with the salt gradient establishes a density gradient and prevents heat exchange by natural convection to some extent.

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Effect of H_2 mole fraction of H_2/N_2 mjxture on the hydrogen permeation mole flux through Pd/Ag membrane with 25μm thickness and 0.02m diameter, was discussed theoretically. The effect was investigated at various feed mole flux (0.05-0.95mol/s.m^2), for total pressure at upstream side of 0.25MPa and membrane temperature of 623K. The results show that the hydrogen permeation mole flux increases with an increase in the feed mole flux, and becomes closer to the permeation mole flux estimated by the ordinary Sieverts' equation. In addition, it is shown that the trend of the increase follows the first order lag system, regardless of the H_2 mole fractions in the feed flow.

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In this research, ion concentration sensing in the electrolyte solution was performed by CARS (coherent anti-Stokes scattering) microscopy using a femtosecond pulsed laser. CARS microscopy realizes high sensitivity, chemically specific and non-intrusive sensing. Sodium sulfate and ammonium chloride solutions are used for measurement and a calibration curve showing the relationship between concentration and CARS intensity was obtained. With the increase in concentration, sodium sulfate solution showed the non-linear increase in CARS intensity at 982 cm^<-1>

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Non-intrusive sensing technique for ions' motion in gas flow was developed using coherent anti-Stokes Raman scattering (CARS) generated by a femtoseconds pulse laser. Negative ion was injected into CO_2 flow and the concentration, measured by an ion counter, increased with increasing values of supply pressure of CO_2. It was observed that the CARS intensity of ionized CO_2 was smaller than that of CO_2. Further experiments will be required to investigate the relationship between the ion concentration and the CARS intensity.

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In this study, we pay attention to the effects of the absorption and desorption of water vapor in clothes on the retaining warmth in the steady state region and we produced a simple device (Fig.1) that is able to control the diffusion of water vapor and heat transfer in a material from the unsteady state region to the steady state region. Two samples (AKN and EKN), of which are knit fabric with and without the absorption and desorption ,respectively are used. At first in the case of heating by dry air, the temperature change of inside and outside of samples are measured. Measured temperature differences of each samples show a same value (Fig.3). And then in the case of heating by moist air, the temperature change of samples are also measured, respectively(Fig.5). But these temperature differences in the steady state show a different value. These results mean that AKN has more heat-retaining than EKN.

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Ammonia is focused on as a no carbon fuel, and the design of the fuel cell vehicle with onboard devices to generate hydrogen from ammonia is performed. The ammonia has higher hydrogen content by percentage than that of methanol or ethanol, and can be liquefied at a normal temperature and a pressure of 0.84 MPa. Therefore the ammonia has a possibility as a new energy, because it can be obtained from biomass energy such as urea.

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We have ivestigated numerically the effect of thermal insulation on the thermal environment of vehicle cabin to reduce the air conditioning load of vehicle in summer time. Double insulation structure is considered using thin insulator (phenolic foam) at the roof of the vehicle in the present study. Thickness of the insulator we have investigated is 10 to 50 mm. At the insulation thickness of 30 mm, temperature increase in vehicle cabin is reduced by 85.7% compared with normal case (no insulation). In addition, at the insulation thickness of 10mm, temperature increase compared with normal case is reduced by 78.3% when thermal conductivity of the insulator is reduced by 5%.

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Currently, there is an increasing demand to reduce greenhouse gas C02 is also in relation to the field of automotive transportation equipment from global environmental issues. There is an increasing demand for systems with less load on the engine more efficient and to automotive air conditioning systems therein. EV car of the future, such as HEV car will be an even greater challenge in particular. To consider how heating to maintain comfort and to reduce the power load larger during heating from this background, by thermal manikin, which is one of the metrics thermal environment based on the heat balance of the human body I We report was evaluated using the equivalent temperature.

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This paper describes the temperature dependence of up-conversion photoluminescence properties of co-doped Y_2O_3:Yb^<3+>/Er^<3+> phosphors. Y_2O_3:Yb^<3+>/Er^<3+> phosphors with various dopant concentrations were prepared by flame spray synthesis, and the photoluminescence spectra of prepared phosphors were examined in the temperature range from 300 K to 1100 K under the infrared excitation light. As a result, the intensity ratio between two emission lines was significantly changed with the temperature, and intensity ratios of all prepared phosphors coincided. regardless of the dopant concentration. Consequently, it is concluded that up-conversion Y_2O_3:Yb^<3+>/Er^<3+> phosphors can be useful for the phosphor thermometry.

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The Great East Japan Earthquake occurred on March 11, 2011, and the huge tsunami that followed brought with it great suffering in areas along the east coast of the Tohoku region. In this region, the process of recovery and reconstructing is still ongoing, but piles of wasted woody biomass have been stacked up everywhere. We have been considering and attempting to determine a productive use of such waste wood biomass. In this background, we focus on a free piston Stirling engine in which high-efficient power generation is possible in the low temperature heat source such as the wood stove. We tried to recover the waste heat by using the small free piston Stirling engine in this study. In this report, the results of the basic performance tests of the free piston Stirling engine are reported.

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Kalina cycle is a power generation system for waste heat source of low temperature. This cycle is mainly used to a single heat source. It is researched how to give the heat for raising the power output of system to the heat source of two or more heat sources. As the result, the power output of system which warming the separator former and latter part of a cycle directly by an exhaust gas, when evaluate for waste water(70℃) and exhaust gas(300℃) as heat source.

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A Low-grade Thermal Energy Conversion (LTEC) is refocused as one of the renewable energy. For the LTEC and Refrigerator/Heat Pump, it is very important to enhance the heat transfer on heat exchanger though the available temperature deference is smaller than conventional thermal system. In the paper, the micro fabrication surface on plate heat exchanger is proposed as one method for enhanced heat transfer coefficient. The manufacture for micro fabrication surface on plate heat exchanger is introduced using surface configuration. The experimental performance test as evaporator is evaluated on comparison with normal surface heat exchanger using HFC245fa. The results show the boiling heat transfer coefficient of micro fabrication surface was larger than that of normal surface.

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Energy harvesting is the process of extracting small amount of energy from environment. Various techniques are being developed to gain electric power from available sources such as wind, vibration, solar, biological, chemical etc. This paper reports the experimental results of unique boiling energy harvester (BEH) which gain the power from kinetic energy of boiling bubbles by means of piezoelectric films. The experimental results indicated that frequency band was broaden with the increase of boiling heat transfer area; and installation of multiple independent piezoelectric films can improve the power generation of BEH.

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In the new century, energy and environmental problems are becoming more critical, the development of natural energy is desired. Low-grade Thermal Energy Conversion (LTEC) is refocused as one of the renewable energy. The aim of this study is to improve the system performance with Double Stage-Rankine cycle. The irreversible loss in heat exchanger can be decreased at this cycle. As a result, the maximum output power of Double Stage-Rankine cycle is larger than that of Kalina cycle. Double Stage-Rankine cycle using ammonia in cycle-No.1 is larger than that using HFC245fa. On the other hand, evaporation pressure of ammonia is 2MPa or more in this calculation conditions.

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In the new century, a Low-grade Thermal Energy Conversion (LTEC) which is Geothermal, Wasted Energy, Ocean Thermal Energy, is refocused on as one of the renewable energy to solve the global warming and the energy problem. This paper investigates on the maximum power and thermal efficiency of Rankine cycle in LTEC condition. The system performance of Rankine cycle is compared among working fluids of different properties. The maximum power with ammonia is largest of that with working fluids. The entropy generation rate with ammonia is smallest of that with working fluids.

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Removal effect of humidity-swing air cleaning method, where sample air is consecutively humidified with heating and dehumidified by cooling, on suspended particulate matter, SPM, is studied. And its possibility for utilizing low temperature heat source was discussed. The removal effect increased with increasing temperature and humidity difference between the humidification and dehumidification. 80% reduction of the total SPM was shown with the heating t0 66℃ and this condition demands a heat source of about 74℃. Thus, it is expected that this method can utilize low temperature difference such as waste heat.

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In this paper, we report dynamic responses of small organic Rankine cycle (ORC) system with latent heat thermal storage to varying heat sources such as waste heat from industries and automobiles. The PCM used in this study was assumed to be a mixture of Li(NO_3)and Mg(NO_3)_2 ・ 6H_2O with melting point and latent heat of 66℃ and 142.6J/kg (to solid), 70.5℃ and 143.4 J/kg (to liquid), respectively and the spherical capsule was made by Ni-plating of 1mm thickness. Numerical analysis of the small ORC system showed that the system efficiency of averaged 10〜11% obtained (considering pump power) and the mean system output power of 260 to 310W using the almost 3kg PCM.

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In order to reuse an exhaust heat from a low temperature heat source, we propose the exhaust heat recovery device which works based on the magnetocaloric effect of a magnetic material. In this paper, the characteristic of the device is studied computationally. The device is constituted of the magnetic material and a magnetic circuit. A numerical simulation is conducted under the parameter such as the temperature of energy source. As a result of the evaluation, it is found that the characteristic of the device is affected by the magnetic flux density and temperature of energy sources.

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Thermoacousitic engines are one of promising devices for utilization of unused thermal energy. However, they need large temperature difference to induce thermoacoustic gas oscillation. In order to solve this inconvenience, the thermoacoustic engine utilizing evaporation and condensation of fluid have been studied. Experiments are carried out by using water as working fluid. The condition of continuous generation of sound wave was clarified in relation to the input amount of heat and cooling condition of stack. The optimum operating condition for heat-sound conversion was also indicated. Based on analysis of sound frequency, the mechanism of thermoacoustic phenomenon in this system was discussed.

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The role of nucleation temperature of constituents used in the synthesis processes of metal boride nanoparticles by RF thermal plasma was investigated. In titanium and boron system, boron is nucleated first due to the high nucleation temperature, then titanium and boron vapors co-condense on the boron nuclei. In aluminum and boron, and yttrium and boron systems, boron cluster is formed after the boron nucleation. The formation of boron cluster is the key process for the boron-rich compound.

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Plasma nitriding for hardening steel surface is achieved by spraying thermal pulsed-arc plasma jet under atmospheric-pressure N_2/H_2 mixture. The quality of nitriding is found to depend on the H_2 flow rate, which has an optimal value. We propose a simple mechanism of this dependence. Moreover, the amount of H_2 necessary for best nitriding can be decreased to 1/20 by changing the way of H_2 addition.

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Non-catalytic hydrogen production from ammonia gas using a pulsed atmospheric plasma have been developed to solve the problems of hydrogen transportation and storages. Ammonia is easily decomposed by electron energy generated by plasma, which is converted to molecular hydrogen and nitrogen by global reaction; NH_3 + e→ 0.5 N_2+ 1.5 H_2. A hydrogen yield attained 100% at an applied voltage of 15kV and an ammonia flow rate of 0.2 L/min. To improve the energy efficiency of hydrogen production, a plasma reactor with a hydrogen separator was proposed. As the hydrogen separator was inhibited the reverse reaction for ammonia formation (N+3H→NH_3), the hydrogen yield attained 100% at an applied voltage of 9 kV and an ammonia flow rate of 0.8 L/min.

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The purpose of this research is the industrialization of hydrogen production using a commercial microwave oven by generating plasma in waste oil. N-dodecane, engine oil and cooking oil were used as a liquid. N-dodecane can be circulated in the experimental device to assume continuous production of hydrogen. The gas production rate was measured, the content of the produced gas was analyzed. The energy efficiency which was expressed as the ratio of the consumed power for the chemical reaction to the microwave power was calculated. The energy efficiency increased with decrease of the microwave power, and reached 14% at the maximum. To improve the energy efficiency the reaction vessel was decompressed. The gas production rate became approximately 2 times larger and the ratio of hydrogen in the produced gas.

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Erosion mechanism of multi-phase AC arc was investigated for the innovative in-flight glass melting technology. The combination of the high-speed video camera and the band-pass filters was used to measure the temperature of the tungsten electrode during the arc generation. Increase of the number of the phases leads to larger molten surface area of the electrode. The dynamic behavior of tungsten vapor in the arc was investigated by using the same system with the high-speed video camera. The strong emission from tungsten was observed. Results indicated that the tungsten mainly evaporated at anodic period.

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In this study, the combustion temperature under non-equilibrium plasma-assisted combustion was measured by spectroscopic measurement. CH rotational temperature was calculated from emission intensity of CH radical using the Boltzmann plot method, and combustion temperature was equal to the CH rotational temperature. In an experiment, it was shown that thermocouple measurement temperature was in reasonably agreement with CH rotational temperature, and the non-equilibrium plasma-assisted combustion temperature was evaluated by CH rotational temperature. In the result, the non-equilibrium plasma raised the temperature of combustion, and it was shown that combustion is promoted by non-equilibrium plasma.

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This study is concerned with the flow around a circular cylinder when a dielectric barrier discharge (DBD) plasma actuator is mounted on the cylinder surface. Velocity fields around the cylinder are measured for the on and off modes of the plasma (pulse modulated drive). As a result, when the actuator is driven at a frequency that the drag force reduces (St=1.0), Karman vortex shedding is suppressed and its location shifts downstream compared to the Base case. On the other hand, at the frequency that the drag increases (St=0.18), the vortex shedding is enhanced.

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The purpose of this experiment is conversion of cellulose dispersed in water as fuel using in-liquid plasma. 27.12 MHz high-frequency plasma was generated in aqueous suspension of cellulose powder or aqueous solution of glucose which is monosaccharide. The gas production rate was measured and the components of the gas production were analyzed. When the concentration of cellulose was 40wt% or higher, the production rate became remarkably high because the ball-like aggregation of hydrous cellulose fell into the plasma and the cellulose was decomposed directly by plasma. On the other hand, the glucose and cellulose with 27wt% or lower was decomposed indirectly by plasma, because the emission spectrum from the species which comprises carbon atom was not detected by spectroscopic analysis.

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To broaden and lower the temperature window of the selective non catalytic reduction (SNCR) of nitric oxide (NO), the use of activated ammonia as the reduction agent was examined. An intermittent dielectric barrier discharge (DBD) was employed as the excitation source for molecular ammonia. The effects of reaction temperatures, length between a DBD and a reactor on NO removal, and addition of Hydrogen were investigated in a lab-scale plug flow reactor.

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This paper describes Tar Decomposition by Activated Cokes-Induced Microwave Plasma. In the study group, we have found that non-equilibrium plasma is generated in a low output at atmospheric pressure by applying a microwave activated coke so far. I tried to decompose tar decomposition retardant is a substance with the plasma. I was able to disassemble the hexane and benzene by using the plasma, it was simulated with tar. I also tried to material and synthetic carbon soot deposited by the reaction. I was able to impart a change in the shape of the soot by using the catalyst.

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