The innovative thermodynamic power cycle called "Allam Cycle" can capture 100% of carbon dioxide emission with no additional efficiency reduction by CCS, and can also get high thermal efficiency equivalent to general combined cycle. The Allam Cycle is an invention of 8 Rivers Capital, which continues to provide technology development services for the program. This unique cycle consists of a closed-loop, high-pressure, low-pressure-ratio recuperated Brayton cycle using supercritical CO_2 as the working fluid. Toshiba is developing this system with NET Power, LLC, Chicago Bridge & Iron Company and Exelon Corporation for demonstrating 25MW-class pilot plant construction. Toshiba's work scope is to design and product brand-new combustor and turbine with development. Design condition at baseload specifies combustor exit temperature as 1150 degree C and pressure as 30MPa approximately. In this paper 1st step of actual pressurized combustion testing results will be introduced and be focused on "world-first" SOMPa achievement in firing with oxyfuel combustion under supercritical CO_2 fluid using natural gas as fuel.

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For the simultaneous achievement of stable electricity supply and carbon dioxide emission reduction, Tohoku Electric Power company is proceeding the construction of Sin-Sendai Thermal Power Station Unit No.3 series (Output: 490MW×2), which are large-capacity gas turbine combined-cycle (GTCC) and replace from aged Unit No. 1 and No.2. Unit No.3 series which are adopted the latest gas turbine firing 1500℃ class turbine inlet temperature (TIT) are planned to achieve the highest level of thermal efficiency in the world (more than 60%LHV). In addition, reflecting our operation and maintenance knowledge in the design stage made it possible to enhance the thermal efficiency still more, which contribute to economy and environmental impact reduction.

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Lignite (brown coal, low-rank coal) fired power plants suffer from the significant heat loss due to the high moisture content in this energy carrier. Water removal from fuel is a dispensable treatment for improving the combustion process, which will foster the efficient utilization of lignite. Superheated steam fluidised bed drying is expected for this purpose in a power generation sector. Understanding drying kinetics of lignite will greatly incorporate design process of a dryer. Physical features as well as the drying behaviour may be divergent among the lignite originated from different depths and positions in a certain main. To reveal and clarify the influence of the geological features, the drying characteristics of several grades of lignite from the Belchatow mine in Poland were investigated. The attempts to clarify the influence of the divergent properties of the investigated samples on the drying kinetics were presented in this paper.

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The thermal and nuclear power plants have been imposed a stable supply of electricity. To certainly achieve this, we built the plant condition monitoring system based on the heat and mass balance calculation. If there are some performance changes on the turbine system components of their power plants, the heat and mass balance of the turbine system will change. This system has ability to detect the abnormal signs of their components by finding the changes of the heat and mass balance. Moreover it helps operators understand problem situation.

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Thermal fatigue crack may be initiated at mixing tee where high and low temperature fluids flow in and mix. The typical frequency of fluid temperature fluctuation downstream from the mixing tee under wall jet condition was reported to be about Strouhal number of 0.2. However, some experiments observed longer-period fluctuations, which may cause severer fatigue damage to piping. Hence, this study tried to simulate this longer-period fluid temperature fluctuation numerically. The simulation conditions were set same as the WATLON experiments: wall jet condition that the jet from the branch pipe flowed along the main pipe wall. The LES dynamic modeling was carried out using the CFD software FLUENT. The distribution of the fluid temperature fluctuation intensity near the wall surface was simulated well qualitatively, while the peak value was overestimated. Frequency analysis of the fluid temperature fluctuation showed that the longer-period fluctuation appeared as well as the well-known typical frequency (St = 0.2).

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We have both the national technical standards and the open standards, that is, JSME codes for power generation facilities are available for the Japanese nuclear power plants in terms of the rules on design and construction, welding and fitness-for-service. They are already established, systematized and incorporated in Japanese regulations, so that they could be referred when the design or the inspections are taken place at the stage of plant construction and the inspections, evaluations and maintenance have been carried out properly during the operations. In the meanwhile, although we have the national technical standards for the nuclear fuels reprocessing facilities, the JSME codes are not available with us yet. So Japan Society of Mechanical Engineers (JSME) who had once drawn out the codes for the Japanese nuclear power plants has started to prepare the codes for nuclear fuels reprocessing facilities with those for Rules on design and construction, welding and fitness-for-service. This report deals with the current status of the codes preparations by JSME.

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JSME Rules on Fitness-for-Service for Nuclear Power Plants provides the Z-factor (load multiplying factor) applicable to the flaw evaluation for Classes 2 and 3 piping. It has been conservatively formulated based on the material properties both for STPT410 carbon steel at 300℃ and STPG370 carbon steel at 200℃ as typical of actual plant condition. Therefore, the applicability of the Z-factor can be just verified for the specific temperatures in a narrow sense. In this paper, Z-factor was analytically calculated based on the material properties for STPT410 and STPG370 carbon steels at room temperature, and the applicability of the present Z-factor to room temperature condition was confirmed in a structured manner.

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This paper describes a high-speed steam jet flow structure, especially near core region, in the case of the pipe rupture. Small scale experiments and CFD calculations were conducted. In the experiment, PIV visualization of the supersonic steam flow was obtained, and compared to the CFD results. As both results show good agreement, validation of the CFD and PIV were clarified.

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Nuclear power plants are designed to prevent the damage of safety installations due to the jet impingement when a pipe is ruptured. We have investigated evaluation methods for the design basis of protection of plants against effects of postulated pipe rupture using computational fluid dynamics analysis (CFD). The steam jet tests using particle image velocimetly were conducted in order to verify the CFD methods. Expanding shape of steam jet, shock wave pattern and spread of steam jet could be visualized. Shapes of steam jet obtained by analysis were almost the same as those by tests. The spread angle of free jet were investigated using CFD. The angles were lower than 10 degree which was described in guidelines of American national standards institute. Results were conservative for evaluations of impact region. However, it is desirable to investigate the conservative angle in detail for evaluation of the jet fluid force.

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[in Japanese]

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Bentonite is considered as a buffer material for geological disposal because of its low water permeability and its ion exchange property. Understanding the behavior of groundwater inside bentonite is important to evaluate the radionuclides transfer for long-term safety, and a measurement system for water content in bentonite without destruction is required. Therefore, non-destructive measurement method using ultrasonic technique is focused on. In this study, transmitted waves of bentonite specimen with differential water content area were measured by two-dimensional scanning of laser vibrometer, and two-dimensional distribution of ultrasonic transit time of the bentonite specimen were obtained. As a result, ultrasonic diffraction through differential water content area was observed. Altogether, ultrasonic measurement for bentonite was validated.

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The KA facility in Rokkasho Reprocessing Plant started the active tests to solidify HAW into the glass in 2007 which was the examination of the final stage before the commercial operation, but the active test had to be discontinued due to the trouble of glass melter operation with the noble metals. After the K-melter equipment and operating conditions were improved in response to the result of the mock-up tests, a series of active tests were restarted in May, 2012 for the purpose of confirming the stable condition before having the pre-use inspection. One year later, these tests were finished with enough confirmation of stability in the state such as glass temperature and controlling the noble metals, and also confirmation of the processing capacity. This paper gives the successful situation in latest active tests of the KA facility by processing the actual waste including the implementation contents in the full scale mock-up tests using KMOC-melter.

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This paper describes the development of the advanced melter in Rokkasho Reprocessing Plant (RRP). This advanced melter is a Liquid Fed Joule heated ceramic melter, and the design of the advanced melter is largely different from the existing one. For the confirmation of the advanced melter performances, the full-scale inactive test was planned to be divided into 2 phases according to the test purposes. The phase-I test had been performed from Nov. 2013 to Feb. 2014, and it was confirmed that the advanced melter had good performances compared with the existing melter. And then, the phase-II test has been performed from Nov. 2014, and the good results are acquired in severe conditions, without periodical washing operation, with increasing glass production rate, etc.

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This paper describes the application of electrical resistance tomography (ERT) to glass melter to monitor the accumulation of the noble metals. To minimize the modification of the melter, existing structures such as thermowells and heating electrodes are used as electrodes of ERT, and the number of electrodes is much fewer than the conventional method. Therefore, Expanding Combination Data Acquisition method (ECDA) is developed and applies to the glass melter. ECDA method uses adjacent method and opposite method as a data acquisition and current injection electrodes are used as voltage measurement electrodes to increase the number of the data. In addition, conductivity images are reconstructed only near the wall to improve the resolution. As a result of applying to the glass melter, the conductivity change inside the melter caused by temperature can be monitored. Furthermore, lower voltage is measured in case of containing the noble metals inside the melter. Therefore, the potential as a monitoring method can be confirmed.

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Supercritical water-cooled reactor (SCWR) is one of the advanced reactor concepts for generation IV nuclear reactors. Material of fuel cladding for SCWR is required long term integrity and durability at metal temperature of 700℃. Then, 15Cr-20Ni austenitic stainless steel (1520S) which has sufficient creep strength at 700℃ was proposed for the candidate materials for fuel cladding of SCWR. In this study, oxidation behavior of 1520S as candidate materials, SUS316L and SUSS 1 OS as comparison materials in supercritical water at 700℃ and 650℃ under 24MPa for 1500h were discussed in terms of: temperature, cold work (CW) and surface finish. The main objective of this work is to predict the oxide behavior of candidate materials after 50,000h which is the estimated maximum operating time of fuel cladding.

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This study investigates the flow field in a flow channel with finger-stacked structure (FSS), which was proposed as a heat transfer promoter for Flibe blanket, by means of PIV measurement matching refractive indices of the channel material and working fluid. The experimental results revealed that turbulence energy was generated in the large velocity shear regions formed behind the fingers, and transported downstream. Then, when the gap between the fingers and channel wall was adjusted to 1 mm, the stagnant region behind the fingers that appeared in the case of 0 mm gap disappeared. In addition, turbulence energy was newly generated from the tips of the fingers. From these results, high heat transfer promotion is expected in the whole heating surface area of the flow channel with FSS setting small gap.

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Wastage phenomena on adjacent tubes (target-wastage) arise from water/steam leak in steam generators of sodium-cooled fast reactors. Target-wastage is likely to be caused by liquid droplet impingement erosion (LDI) and Na-Fe composite oxidation type corrosion with flow (COCF) in an environment marked by high temperature and high-alkali (reaction jet) due to sodium-water reaction. The authors derived new wastage correlations from COCF and LDI data based on influencing factors which were formed on the periphery of an adjacent tube. In this report, the applicability of new wastage correlations were confirmed by using data of sodium-water reaction test with tube bundle under practical steam generator operation condition.

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Self-wastage comes from water/steam leak through the penetrating crack caused in the steam generator tube of sodium-cooled fast reactor. When the self-wastage proceeds to inside wall of tube, breach area and water leak rate will be larger, then, it will be likely to spread the affected area caused by sodium-water reaction. It is very important to clarify the self-wastage behavior for locally affected region and detection of the water leak in real plant. In the 1^<st> report, the authors have performed the self-wastage experiments for the pinhole type micro crack. In this report, fatigue crack type self-wastage experiments were carried out to evaluate the effect of wastage form/geometry and water leak rate, it was confirmed that initial defect geometry, such as pinhole and fatigue crack, does not strongly influence to self-wastage rate.

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Overheating tube rupture of adjacent tubes arises from water/steam leak in steam generators of sodium-cooled fast reactors. It is very important to predict the tube wall stress (tube wall temperature) with a high degree of accuracy on evaluation of overheating tube rupture, and is crucial to estimate quantitatively material strength standard which is one of the major influencing factor. Therefore, in present study, the authors carried out tube rupture experiments with rapidly-heating which were simulated the tube thermally-affected by sodium-water reaction jet, and evaluated quantitatively failure hoop stress and failure time. Then, the authors confirmed that existing stress strength standard was applicable to thin diameter and thick-walled single tube in case of sodium-water reaction exceeding 1300 degC under practical steam generator operation conditions.

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High cycle thermal fatigue on a structure caused by thermal striping phenomena is one of the most important issues in the design of fast breeder reactors. In development of numerical simulation codes and application of the codes to plant design and estimation, implementation of verification and validation (V&V) is indispensable. A procedure called as V2UP (Verification and Validation plus Uncertainty quantification and Prediction) has been made by referring to the existing guidelines on V&V and the methodologies of the safety assessment. Phenomena analysis with the PIRT (Phenomena Identification and Ranking Table) method based on the nine-step process used by the USNRC for the next generation nuclear plant development was employed at the first step of the V2UP. Through the first step of the V2UP with PIRT method, the conceptual model for the numerical estimation of high cycle thermal fatigue was successfully constructed.

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This study evaluated experimentally the effect of influence of the inflow condition upon the flow field in the cold leg piping, which comprises three 90° elbows, of the primary cooling system of Japan Sodium-cooled Fast Reactor by using a swirling flow generator upstream of the piping. Flow visualization experiment was conducted to reveal the velocity fields of the flow in the piping. The experiment showed that the flow separation did not appear in the intrados of the 1st elbow and velocity of the swirling flow downstream of the 2nd elbow increased compared with the case of a developed turbulent inflow. These results imply the possibility that Flow-Induced Vibration is reduced by swirling flows as the inlet condition.

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Drying process consumes great amount of energy, but, by attaching the evaporation-dehydration system called VRC (Vapor Re-Compression), energy consumption can be reduced significantly. In this study, authors take up a biomass power plant that burns empty fruit bunches (EFB) as fuel. In this paper, an original process is called P-org. Ho et.al. proposed a process (P-Ho) attached SSD (Super-heated Steam Dryer) and HAD (Hot Air Dryer) to P-org. The authors proposed a process (P-VRC) replaced with VRC instead of HAD in P-Ho. Then, P-VRC.HEN is derived by optimizing HEN (Heat Exchanger Network) in P-VRC. P-Ho and P-VRC.HEN are processes optimized in operating point. As a result, net thermal efficiency is maximized in P-VRC.HEN, 30.1%, which is 2.2 points higher than that of P-Ho.

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Energy consumption in commercial sector is rapidly increasing in Japan. In this research, the purpose is the construction of an energy saving supply system in commercial buildings. Therefore, a middle scale city in Japan with 4 facilities (hospital, hotel, office and store) was assumed. In this report, results from the office type facility in particular are shown. Standard energy supply system and the improved system were considered and the running cost in each system was estimated. Comparing running cost in standard system with that of the improved system, the optimal energy supply system was obtained. The main conclusions from this experimental analysis are as follows. When PV, gas boiler, and turbo refrigerator are introduced in office, amount of CO2 emissions become minimum. On the other hand, when PV, gas boiler or latent heat recovery type water heater, and Electric Air conditioner are introduced, lifecycle cost is minimized.

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In recent years, the importance of business continuing planning (BCP) of a building is increasing and in this context, gas engine generators and emergency generators attract attention. However, when introducing such devices, there is no guideline based on the evaluation of introductory merit from the viewpoint of both usual and emergency cases. In this paper, the guideline is proposed based on the simulation result taking account of a disaster risk, device installation cost and a running cost with hotels, hospitals, offices, collected houses as target buildings. The running cost was called for by simulation. The introductory support matrix was created using these results, and the plan for a consumer to introduce a device was shown.

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The sugar mill, which is the main industry in Tanegashima, recycles sugarcane bagasse as a fuel but concurrently generates a massive amounts of unused heat below 200℃. On the other hand, many factories in Tanegashima uses heavy oil-fired boilers to generate a process steam up to 100℃ all year around. In order to resolve this spatial and temporal mismatch, we propose the application of heat storage and transport system using steam adsorption and desorption cycle of zeolite. Process flow diagram of the sugar mill was developed using a commercial process simulation software. Adsorption and regeneration tests were performed to obtain the maximum adsorption amount, initial adsorption amount and regeneration rates, which were used to calculate heat storage capacity, the transport capacity of zeolite and the fuel reduction rate of the oil-fired boiler were calculated. As a results, the maximum fuel reduction rate reaches 48% while it is restricted by the operating condition of the boiler.

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In vanadium redox flow battery, energy efficiency decreases mainly because of ohmic loss IR_<cell> and concentration overpotential η_<con>. Especially capacity loss by early shutdown timing of charge and discharge process is strongly affected by η_<con>, which depends on mass transfer of active species to reaction area. In this study, we conducted charge-discharge experiments with a single cell battery in order to investigate the behavior of cell voltage around shutdown and elucidate the relationship between mass transfer coefficient k and electrolyte flow condition. It was shown that that the k is proportional to 0.5〜0.6th power of mean electrolyte flow velocity ν, and the coefficients are different for the charge and discharge processes.

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Ground source heat has recently attracted considerable attention as renewable energy. The temperature of the underground less than 150m depth is constant by geothermal energy throughout a year. Thus, a ground source heat pump (GSHP) system is one of saving energy systems. The GSHP releases heat at a cooling mode to the underground and extracts heat at a heating mode from the underground. This paper describes a characteristic of extracting and releasing heat to the underground by exchanging heat of GSHP that use direct expansion method. As a result of the experiment, the releasing heat increased the underground temperature of 16.1℃ in the cooling mode. The extracting heat decreased the underground temperature of 18.5℃ in the heating mode. It was found that, however, the underground temperature recovers to the initial state during stop of the GSHP.

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It is important for a design of an adsorber to clarify adsorbed refrigerant distribution in adsorbent bed during transient conditions with adsorption or desorption, because the adsorption and desorption process is complex phenomena with heat and mass transfer and strongly effect on the cycle performance of an adsorption refrigerating cycle. Adsorbed refrigerant distributions in an activated carbon particle bed in a metallic rectangular vessel had been quantitatively measured by a neutron radiography method. Ethanol was used as the refrigerant. An umbra method using a checked neutron absorber grid was applied for a quantitative measurement. The measured mass attenuation coefficient of ethanol was 0.386 m^2/kg. It was confirmed from the measurement for an adsorption bed in adsorption equilibrium that the adsorption amount could be quantitatively measured by the method. From the experiments of adsorption and desorption process with heat transfer, it could be clearly visualized that the adsorbed amount in the adsorption process was strongly affected by the position of the heat-transfer surface. In the desorption process, the effect was relatively small, because the heat diffusion in the adsorption bed might be enhanced by regenerated superheated vapor flow.

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As a feasibility study on waste heat recovery of exhaust gas of automobile, heat transport characteristics of Bubble Actuated Circulating Heat pipe, BACH, were experimentally measured. Maximum temperature of exhaust gas was assumed to be about 350℃. Heated section of heat pipe BACH was double-tube type, i.e. working fluid was set between inner and outer tube, and hot air flowed through inner tube. Experimental parameters were gas temperature, amount of working fluid, inclination angle and kind of working fluid, i.e. water and antifreeze solution. The obtained results show that maximum heat transport rate reached about 1400 W and heat transport rate was not strongly affected by the amount of working fluid.

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Hydrogen H_2 for fuel-cell power plants is commonly manufactured from hydrogen-rich materials such as hydrocarbons C_nH_m and alcohols C_oH_p(OH)_q, using steam-reforming methods with catalysts. Recently, the authors have investigated the optimum conditions for efficient and endurable steam reforming (Shinoki et al., 2011). In the present study, the authors investigate the optimum conditions as well as Shinoki et al., especially focusing on both the influences of liquid-hourly space velocity LHSV upon concentrations such as C_<H2>, C_<CO2>, C_<CO> and C_<CH4> and the influence of LHSV. As a result, all the concentrations are close to the theory of Shinoki et al. except for the case at low T_R and high LHSV. To settle the inconsistency of this exceptional case, the authors propose a new theory using some chemical reactions related with acetaldehyde. Furthermore, the authors discuss the influences of T_R in addition to LHSV based on the Arrhenius equation.

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Ammonia is a hydrogen storage material that may solve several problems related to hydrogen transportation and storage in the hydrogen economy. Catalytic thermal decomposition is a promising technique for producing hydrogen from hydrogen, however treatment of unreacted ammonia is a critical issue for fuel cell use. We investigated atmospheric plasma decomposition as a new hydrogen production device. We observed that molecular ammonia was rapidly decomposed by electron energy in the plasma and was converted into molecular hydrogen. The hydrogen production was increased by the ammonia concentration, but hydrogen conversion was only 16%. To improve these problems, a new high voltage electrode was developed, which was equipped with a hydrogen separation membrane. Hydrogen conversion was drastically increased to 0.3 L/min at a NH_3 flow rate of 1.0 L/min by the high voltage electrode with a hydrogen separation membrane.

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Femtosecond laser pulses (fs pulses) can generate hydrogen bubbles. The fs pulse leads extraordinary phenomena due to their extremely higher energy density than usual laser pulses (nano- or pico-second). We think the bubble formation by fs pulses must be different from the ordinary laser-induced cavitation. In this study, a single fs pulse was focused on water in a glass cell through several types of lens. We visualized bubble formation processes from sub-picosecond to microsecond order through time-resolved visualization. We found out a strange time-series process of refraction index changes of the media irradiated by the fs pulse: the bubble nucleation, rapid growth of bubble and interesting bubble properties. Based on these results, we will discuss a relationship between those and fs pulse peak intensity, and production method for hydrogen through the fs pulses.

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This paper describes the evaluation results on long-term stability of hydrogen gas meters in relation to the demonstration town project of pure hydrogen type fuel cells. We developed the gas meter calibration system that was traceable to the national gas-flow-rate standard in NMIJ/AIST. Four different type gas meters, which were an ultrasonic, a thermal type, a gear type, and a diaphragm type, were calibrated by the calibration system, and were evaluated at the demonstration town for three years. The results showed that an ultrasonic type and diaphragm type gas meters had good long-term stability, and that measurement uncertainties of these gas meters were small enough.

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High pressure PEECs (Polymer Electrolyte Electrolysis Cells) possibly suffer from hydrogen gas crossover driven by the large pressure difference between cathode and anode, and the crossover decreases the current efficiency. As a countermeasure of the crossover, controlling wettability of cathode porous current supplier is proposed here. Higher wettability may promote detachment of bubbles from the supplier, and reduce the retention time of the bubbles there, resulting in less crossover. This study evaluates this wettability effect on the crossover experimentally. Experiments with changing the wettability of the supplier revealed that higher wettability reduces the crossover and increases the current efficiency. However, under high pressure condition, the wettability effect does not appear clearly. In the experiments, accuracy in hydrogen crossover measurement value is important. This issue is addressed with the new measurement device which measures hydrogen concentration in oxygen evolution side.

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At cold startup of a polymer electrolyte fuel cell PEFC at -10 ℃, the produced water remains as supercooled water before it freezes, and then the shutdown occurs with ice layer formation between the cathode catalyst layer (CL) and micro-porous layer (MPL). This study investigated ice formation behavior during the cold startup with supercooled water in PEFC by measurements of cold start characteristic and observations of the cathode CL using a Cryo-SEM. The ice layer observed at the interface became thicker gradually during the startup, and this suggested that the produced water moves through ionomer in the CL. Basic investigation of the water transport through the ionomer and its driving force was conducted, and introduction of a hydrophilic MPL was tested to improve the cold start characteristics, longer startup period.

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In this study, ECA(Electrochemical area), performance, CV(cyclic coltammetry) and STEM-EDS (Energy Dispersive Spectroscopy) were measured in order to improve the ionomer coverge rate of inside of secondary aggregates in PEFC (Polymer Electrolyte Fuel Cell) and investigate its mechanism through varying the addition proportion of IPA (ispropyl alcohol) and Nafion. As results, the followings were understood. In the case of increasing addition proportion of IPA, EGA were increased, activation polarization and diffusion polarization were decreased and performace was improved. The addition proportion of Nafion had little influence on EGA as it was higher than optimized value, but as it was lower than optimized value, the mechanism of the influence of addition proportion of Nafion on EGA was different from former. In addition, the existence of secondary aggregates inside the layer of catalyst was confirmed, and it was clarified that low content of Nifion inside secondary aggregates was one of the reasons of low utilization rate of Pt in PEFC.

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If the flow channel in the PEFC separator is plugged with the PEFC separator is plugged with the liquid product water, pressure loss increases and the flow is destabilized to cause serious deterioration of the power generation performance. It may be probable that occurrence of the channel plugging can be avoided if the surface wettability of the channel wall is circumferentially non-uniform. In this work, systematic pressure drop measurements were carried out for the gas-liquid two-phase flow in small rectangular channels of various wettability distributions. It was found that the fluctuation of pressure loss that is frequently encountered in uniform wettability channels can dramatically be mitigated by the use of the flow channel of circumferentially non-uniform wettability.

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A one-dimensional numerical model of a nickel-infiltrated gadolinium-doped ceria (Ni-GDC) electrode has been developed to investigate the effects of electrode microstructure on performance. Electrode microstructural information was obtained with focused-ion beam tomography and microstructural parameters were quantified, such as tortuosity factor, surface information and phase sizes. These have been used to estimate the effective transport coefficients and the electrochemical reaction rate in the electrode. GDC was considered as a mixed ionic and electronic conductor and hence the electrochemical reaction is assumed to occur on the GDC-pore contact surface, i.e. double-phase boundaries (DPBs). Sensitivity analysis was conducted to investigate the effect of electrode microstructure on both transport properties and electrochemical activity. The developed model offers a basis to understand the electrode-microstructure performance and to further optimize the electrode microstructures.

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Rechargeable batteries for energy storage are receiving remarkable attention due to the spread of renewable energy. Solid oxide Fe-air rechargeable batteries are among the most novel concept and expected to be high-performance and cost-effective energy storage systems. Despite their capability to store and provide electric energy, they are not ready for practical application because of the lack of knowledge on the reduction process within the porous iron during charge process. In this study, prous iron oxide pellets were reduced and their submicron-scale microstructures before and after the reduction were analyzed in 3D, based on which a practical model taking into account the gas diffusion in porous media and the reduction reaction on the reaction interface was developed. This offers a basis to understand the rate-determining process during charging and further improve the battery performance.

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Experiments using a 1 kW tubular-type SOFC with an AGR system driven by a variable flow ejector were conducted without externally steam feed at part-load conditions to evaluate effects of recirculation ratio on the AGR-SOFC performance. The mole fractions of chemical species were measured using a quadrupole mass spectrometer and an optical dew point transmitter, thus the recirculation ratio could be identified from the anode gas composition. The recirculation ratio could be controlled from 0.59 to 0.69, because the nozzle exit opening area can be changed corresponding to the needle position inside the nozzle. The mole fractions of H_2O and CO_2 at SOFC inlet increase with recirculation ratio, and thus the mole fractions of the fuel components (i.e., CH_4 and H_2) decrease. However, almost no effect of recirculation ratio on the SOFC output power was observed.

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Adsorption cooling systems are considered as an attractive alternative of vapor compression cycles as they have the ability to operate by low-temperature waste heat or renewable energy sources. However, the main drawback of these systems is their low performance. To improve the system performance it is essential to understand adsorption phenomenon and to have an accurate measurements of adsorption characteristics of adsorbent/refrigerant pair. Among these characteristics, adsorption kinetics plays a crucial rule on the system performance. Therefore, the aim of this study is to investigate the effect of isostatic heat of adsorption on adsorption kinetics of activated carbon powder/R32 pair. Experiments have been conducted using volumetric method within adsorption temperature ranging from 30 to 70℃ and pressure up to IMPa. Data extracted from this study are useful for designing and evaluation of adsorption cooling systems.

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In order to achieve maximum performance, it is important to understand how many factors influence the performance and how much of an impact can a factor has. Therefore, in this study the cooling effect and the coefficient of performance, COP of an adsorption cooling cycle using activated carbon powder/ethanol pair has been experimentally investigated by changing the heat source temperatures ranging from 70 to 90℃ and evaporator inlet water temperatures ranging from 15 to 25℃. Moreover, we compared the experiment result with theoretical calculations, it was shown that increasing the heating source temperature and evaporating temperature can give significant results on the COP and cooling effect.

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The objective of this study is to investigate the performance of double effect adsorption cycles with various adsorbents. Double effect cycles have higher COP than conventional single stage adsorption cycles. Two types of double effect cycle were examined by means of static cycle simulation assuming equilibrium states where the cooling effect is dominated by driving heat source temperature, cooling water temperature, evaporator pressure and condenser pressure. Because double effect cycles consist of two adsorption reactors, there exists freedom to select adsorbent for them. This study estimated the performance with conventional silica-gel, AQSOA-Z01 and Z02. The results suggest that the combination of Z01 and Z02 will be effective for the double effect cycle to utilize adsorption heat.

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A novel incineration power generation system, in which are appended with bottoming power generation system and solar collector apparatus, has been investigated from view point of energy saving and heat island problem. At first, both the input heat amount to power generation system and the steam conditions at turbine inlet were investigated by using waste incineration plant annual operation data. Next, optimum working fluid was examined by calculation results of Rankine cycles about several organic or inorganic working fluids. Ammonia was selected as an optimum working fluid of low temperature waste heat driven power generation system. Furthermore, performances of the proposed power generation system were estimated in cases for standard operation condition and severe summer condition.

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The linear generators are the systems primarily used to convert the acoustic power output of a thermoacoustic engine into electrical power. Here, we performed an experiment on the output characteristics of an impulse turbine, which is a technique used to produce an electric power from an oscillatory flow. Argon (1 MPa) was used as the working fluid and the impulse turbine was embedded in an acoustic field. In this study, we measured the dependence of the acoustic to the electric power conversion efficiency on displacement amplitude.

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The discharge coefficients of the flow nozzles based on ASME PTC 6 are measured in wide Reynolds number range from Re_d=5.8×10^4 to Re_d=1.4×10^7 and the equations of the discharge coefficients are developed for the laminar, the transitional and the turbulent flow ranges. The equation of the discharge coefficient consists of a nominal discharge coefficient and the tap effect. The nominal discharge coefficient is the discharge coefficient without tap, which is experimentally determined from the discharge coefficients measured for different tap diameters. The tap effects are correctly obtained by subtracting the nominal discharge coefficient from the discharge coefficient measured. The deviation of the present experimental results from the equations developed is from -0.06% to 0.04% for 3.0×10^6<Re_d<1.4×10^7 and from -0.11% to 0.16% for overall Reynolds number range examined.

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