This work is aimed at investigating how the solutions adopted for the SRF (short rotational forestry) can be applied to oleaginous cultures for bioenergy production with a dual fuel diesel engine. The method is based on four sub-systems: a seed press for oil production, a downdraft gasifier, a biodiesel conversion plant and a dual fuel biodiesel IC engine for CHP (combined heat and power) production. The plant is analytically modeled except for the IC engine that was tested via experimental analysis. Results showed that, in the hypothesis of 8000 hours/year of power plant run, a surface of 27 hectares can supply enough syngas and biodiesel to run a CHP unit with nominal electrical power of 13.61 kW. Moreover, the experimental analysis outlined how the engine running with dual fuel is not almost affected by significant losses in its performance. Besides, the use of syngas yields strong benefits in terms of soot emissions (measured by an opacimeter), as well as in terms of brake fuel conversion efficiency.

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This work is aimed at demonstrating by modeling and simulation how a synergy of state-of-the-art technologies can boost of about 50% the maximum power output that can be obtained from maize silage biogas power plants. The starting point is the subdivision of the maize plant into grains and stover (that is composed of cobs, stalks and leaves). Grains are rich of starch, soluble sugars, fat and protein suitable for the anaerobic digestion, instead the stover is rich of hemicellulose and lignin which are characterized by a slow and incomplete degradability. This consideration brings to the core of the paper: grains are used as fuel in an anaerobic digester, while stover is converted into syngas in a fixed bed downdraft gasifier reactor. The biological degradation of grains is based on equilibrium kinetic models obtained from literature review, the stover gasification is modeled with an equilibrium model implemented in Python^<TM> language. Biogas and syngas streams are used together as fuel in a Solid Oxide Fuel Cell (SOFC) conversion unit modeled through a Matlab^<TM> script. Simulations were done considering a conventional maize silage biogas power plant with 100 kW electrical nominal power. Results outlined that the SOFC has a higher conversion rate than the conventional IC engine, in fact the replacement of the generator with a SOFC increases the power output of the plant to about 118 kW. Finally, the combined effects of coupling digestion of grains with the gasification of the stover and the use of a SOFC boost the peaks power output to 150 kW.

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Steam turbine vanes are usually manufactured in sectors (grouped vanes) consisting of several airfoils. As a consequence, the vane structure exhibits closely spaced natural frequencies of Toop (Tangential out-of-phase) modes, in which each vane in a sector vibrates like a fixed-fixed beam in a different phase. In such a steam turbine vane, the forced vibration and the self-excited vibration of Toop modes may become a serious issue. Therefore, in the design of the steam turbine vane, it becomes indispensable to evaluate the resonant response and the stability of Toop modes under the high loading condition. In this study, first, the vibration characteristics of steam turbine vane with grouped vane structure are studied by use of the results of FE (Finite Element) analysis. Especially, the vibration characteristics of Toop modes are examined in detail. Second, the reduced order model (the equivalent spring-mass model) of the whole vane structure is assembled, based on the results of FE analysis. Finally, the forced response analysis of the mistuned whole vane structure is carried out, using the reduced order model and the Monte Carlo simulation. From these results, the vibration response characteristics of Toop modes of the whole vane structure are clarified.

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This paper reports output increase of combined cycle power plants by cooling their suction air using water spray nozzles, in order to deal with tight supply-demand situation of electricity and to save fuel consumption. The splay nozzles installed previously are pointing to downstream of air flow or downward. We tried to improve its cooling efficiency by optimize the spray nozzle angle. Laboratory experiments were conducted for that purpose. Suction air area was 2 meter square, and air flow velocity was set to approximately 2 meter/sec.by a blower. Temperature and related humidity were set to 33 centigrade and 60 percent respectively by air-conditioning units. As a result, a method that the splay nozzles are pointing upstream of air flow showed the best performance. The same tendency was also observed by finite element analysis using a CFD program. This method was applied at both a working combined cycle power plant of 380 MW and that of 500 MW on trial. Temperature of cooled air was measured using a number of thermocouples in suction air room at each plant. Consequently, it was observed that the cooling efficiency was improved by ten percent and several percent respectively, and plant output was increased by approximately 2 MW at the 380 MW plant.

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Energy generation in isolated areas is to this day a challenge for many regions. In islands, power generation is mainly done with diesel generators, but the high costs and energy spent on transporting fuel and the CO_2 emissions generated from its operation have been raising concerns lately. In this study, a hydrogen fueled micro-grid using solar photovoltaics and heat collectors is proposed for power generation in isolated areas. The grid consists of a central facility with a main power generation system, connected to a number of residences. An optimization model is built which finds the size and component capacities of the micro-grid at which hydrogen consumption per household is minimized. The model is run using energy demands and irradiation data from the areas of Kansai and Kyushu, Japan. The model was able to find the trends at which hydrogen consumption can be minimized. Primary energy consumption by the grid showed high savings compared to the conventional system. Potential sources of hydrogen fuel for the proposed grid are discussed as well.

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A power generation system with low CO_2 emission utilizing methane hydrate (MH) is proposed in this study. Carbon dioxide capture and storage (CCS) technique is employed to reduce the CO_2 emission. The performance of this system was evaluated by using a static process simulator. The power generation system is based on the Brayton cycle and is comprised of a compressor, gas turbine, and combustor, all of which can fit in the limited space available on the vessel which is anchored over the MH reservoir. In CCS, the emitted CO_2 was absorbed by amine which is typical chemical absorbent of CO_2. The performance of the amine was evaluated in this study. The calculation result shows that the thermal efficiency of the system is decreased with the increment of the pressure because of the mechanical work of the compressor. The thermal efficiency of the system using the amine absorption system was increased about 15% than that of the system with the direct dissolving system. When the flow rate of CH_4 was 5,000 kg/h, the output power of the system was 30,000 kW that was the feasible value for energy supplying system.

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Bird strikes in wind farms have increased exponentially due to rapid spread of wind power generation world widely. Particularly, rare bird species registered in Red List so called should be protected from turbine collision death. To this end, a variety of strategies were examined with help of biologists but concrete solution has not been established yet. Our approach is to detect birds flying into wind farms optically based on real time image processing system, which also has a function to distinguish bird species. In this paper we present a series of image processing methods for flying wild birds, which enables bird species identification. Although number of sampled images is limited at present, we confirmed that introduction of eight kinds of wire-frame models to real bird shadow images enabled significant increase of the species identification probability only from a single instantaneous photograph. This yields to 90% correct identification as five image frames are sampled.

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In this study, a desiccant outdoor air-conditioning system that uses high-temperature chilled water (approximately 20 ℃) and low-temperature hot water (approximately 55 ℃) produced by a high-efficiency heat pump, and hot air produced by solar heat collectors, was proposed. This system treats the total heat load of outdoor air and indoor latent heat load in commercial buildings. In the proposed system, solar heat is effectively used for regeneration of the desiccant in summer and for pre-heating of ventilation air in winter. We have constructed a prototype of this system and evaluated the coefficient of performance (COP) of the entire desiccant air-conditioning system using the measured values of electric energy consumption and treated enthalpy between the outdoor air and supply air.

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Effect of Reynolds number on the torque and power characteristics of a small straight-bladed vertical axis wind turbine has been investigated experimentally under various wind velocity. The maximum mean torque coefficient and the maximum mean power coefficient increase with increasing Reynolds number based on wind velocity and representative length of wind turbine. The tip speed ratio for the maximum mean torque coefficient is almost independent of Reynolds number. Otherwise, the tip speed ratio for the maximum power coefficient increased as increasing Reynolds number. When the curvature parameter and the solidity represented forms of the wind turbine are same, the wind turbine performance can be successfully explained by the simple analytical functions, namely, the mean torque and the mean power coefficients can be represented well by the logarithmic functions of Reynolds number and quadratic or cubic function of the tip speed ratio. The proposed approximate equations successfully predict the experimental data for the particularly higher tip speed ratio.

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Coal is a very important energy resource for power generation. However, coal releases more carbon dioxide (CO_2) than other fuels used in thermal power generation. There are some technologies that capture CO_2 from power generation systems, but carbon capture technologies negatively affect the thermal efficiency of power generation. We have tested both chemical and physical CO_2 absorption equipment in order to improve the efficiency of a coal gasification power generation system with CO_2 capture in the EAGLE Project. In a feasibility study on IGCC with a CO_2 capture system, based on our test results, we found that when a CO_2 capture system is installed in an IGCC, net efficiency is 38% or more, and the physical CO_2 capture system achieves a 13% reduction in energy loss compared with the chemical CO_2 capture system.

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The system for high utilization of LNG cold energy is proposed by use of process simulator. The proposed design is a closed loop system, and composed by a Hampson type heat exchanger, turbines, pumps and advanced humid air turbine (AHAT) or Gas turbine combined cycle (GTCC). Its heat sources are Boil-off gas and cooling water for AHAT or GTCC. The higher cold exergy recovery to power can be about 38 to 56% as compared to the existing cold power generation of about 20% with a Rankine cycle of a single component. The advantage of the proposed system is to reduce the number of heat exchangers. Furthermore, the environmental impact is minimized because the proposed design is a closed loop system. A life cycle comparative cost is calculated to demonstrate feasibility of the proposed design. The development of the Hampson type exchangers is expected to meet the key functional requirements and will result in much higher LNG cold exergy recovery and the overall system performance i.e. re-gasification. Additionally, the proposed design is expected to provide flexibility to meet different gas pressure suited for the deregulation of energy system in Japan and higher reliability for an integrated boil-off gas system.

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Recently, we have experienced the industry issue of overheating failures in turbine-valve drain piping. The cause of the overheating has been believed to be thermo-acoustic phenomenon, which is known as H-S tube, but there have been little information about the thermo-acoustic failures. This report shows test results obtained by impinging jet air to a tube having close end that is simulating the drain pipe. The tube length is up to 2m, much longer than the previous works. The relationship between the heating rate and the pressure fluctuation in the tube is examined experimentally. The results show that there are two heating states, standing-wave type and non standing-wave type, which are similar as the previous works about shorter tubes. The relationship is also organized in dimensionless expressions, to be able to estimate the amount of heat generated in the steam. Finally, two countermeasures are proposed: one is to open the drain valve slightly, and the other is to add a muffler. In the case of the muffler, it should be noted that the upstream side of the muffler will still be overheated.

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The Integrated coal Gasification Combined Cycle (IGCC) is a highly effective power generation system where a gas turbine is operated with gasified coal in a gasifier. The NAKOSO IGCC Demonstration Plant was constructed by Clean Coal Power R&D Co., Ltd. (CCP) and CCP had been conducting the various tests for commercialization since September 2007. The Demonstration Project finished in March 2013. CCP was absorbed by Joban Joint Power Co., Ltd. on April 1st 2013. The IGCC plant has been called Nakoso Power Station unit No.10 and has been operated as a commercial plant. In 2013, the consecutive operation hours recorded 3,917 hours which was much longer than the previous record and was considered to be the world record as the IGCC at the moment. The 2013 fiscal year's capacity factor was about 50%. In 2014, it was begun to use coal other than plant-designed coal. Tokyo Electric Power Company (TEPCO) has been advancing the plan to construct two 500MW-class IGCC plants in Fukushima prefecture. The one will be located at TEPCO's Hirono Power Station and another will be located at Nakoso Power Station. Joban Joint Power has been cooperating in the Nakoso project. The technologies acquired by the commercial operation will be provided for the project. Joban Joint Power will keep supporting the project positively as much as possible. This report describes the commercial operation condition etc. of Nakoso Power Station unit No.10 of Joban Joint Power Co., Ltd. from 2013FY to 2014FY.

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Noticing the color variation of torrefied biomass with pyrolysis process, a non-invasive evaluation method of torrefied biomass properties is investigated. It is assumed that the properties of torrefied biomass mainly depend on its mass yield, and the relationship between mass yields and colorimetric values defined by CIELAB is experimentally examined. The results obtained for torrefied Japanese cedar are as follows. In the case of the trunk sample for L* above 45, the mass yield is expressed as a function of L*, and in the case of the trunk and bark samples for L* below 45, the mass yield is expressed as a function of color coordinate, a*. From the comparison between predicted mass yields and experimental data, it is found that the proposed experimental correlations with the colorimetric values can evaluate the mass yield within an accuracy of ±10%. The energy properties of torrefied biomass such as elemental contents, energy density and energy yield are correlated with the mass yield. When the torrefied biofuel is produced, the quality control concerning energy properties is indispensable, and the optimum mass yield as well as energy properties are easy to be checked by using the present non-invasive method.

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An optimal operational planning problem of residential energy system has been formulated by Mixed Integer Linear Programming (MILP). The decision variables of optimal operational planning problem are energy and mass flows, equipment's operating statuses, and energy level of storage. Many kinds of energy supply equipment are available for householders in Japan. Of course, in operational planning problem, the increase of integer variables which means equipment's on/off status, is linked to the increase of calculation time. It is important to assess the impact of introducing an energy system for a house based on the suitable planning horizon of this problem. Energy storage brings the energy in the form of hot water and electricity to the next day. The operational strategy of energy system including storage should be evaluated through few days toward various energy demand. The optimal planning problems become large scale because many pieces of equipment to introduce and long evaluation period are required. This paper analyzes characteristics of energy systems caused by planning horizon. Additionally, we propose a hierarchical method as heuristic method for solving large MILP problem easily, and the proposed method is tested the effectiveness. Our finding shows that the proposed search method for better feasible solution has good performance in comparison with default settings of conventional MILP solver in terms of calculation time.

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Some cracks were found at the first stage discs of gas turbine rotors made of Ni-base superalloy. There were inter-granular cracking and observed to be highly stressed and damage sensitive locations with less potential for oxidation, which is thought to occur due to hold-time cracking. In this study, laser peening technology for gas turbine components was developed to improve material properties of Ni-base superalloy Alloy 706, and the effects on the material properties were examined. Laser peening is a novel process to induce compressive residual stress on material surface by irradiating focused high-power laser pulses. Several durability tests, such as thermal aging treatment test and stress aging test, were performed under thermal power plant operation conditions. The value of residual stress was over -500 MPa after exposed 3000 hours at 500℃. In addition, surface residual stress was almost the same value in case of applied stress was less than 800 MPa at 500 ℃. Therefore, the effectiveness of laser peening treatment under the running temperature was confirmed.

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In this work, heat transfer in a heating-up mode of the LiBr/water absorption heat pump (AHP) was experimentally studied. The experiment was performed for a single spiral tube which was employed in the absorber. The inside and outside of the tube are subjected to a film flow of the solution and exposed to the atmosphere, respectively in the modeled experiment. The maximum temperature of the solution was observed not at the entrance but in the region a little downward from the entrance in the tube. The average convective heat transfer coefficient between the solution film flowing down and the inside wall of the tube was determined from the total heat transfer rate estimated by the enthalpy balance of the solution at the inlet and outlet of the tube. The film heat transfer coefficient fell down with rising Reynolds number of the solution stream. The trend agreed with that obtained for a straight smooth tube in absorber working in a refrigeration mode reported in the past. However, the heat transfer coefficient in the present work was greatly enhanced in low Reynolds number rather than the past one for a smooth tube due to a turbulent promotion effect of the solution in a spiral tube.

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I studied an aeration system using a simple pump driven by a Savonius wind turbine installed on a float. This simple pump uses centrifugal force to draw water from the bottom layer to the surface of a pond. Based on previous studies, I designed and produced a demonstration model, 1700 mm high, measured from the surface of the water of high, 2300 mm long and 2300mm wide. The floating and the rotational performance of the model have been confirmed. By improving the waterproof mechanism of the shaft and bearing, and examining the material, rotation from a lower wind speed of 5m/s has been achieved. In addition, adjusting the diameter of the pipes, which are components of the simple pump, revealed that the torque characteristics of the pump can be adapted to the characteristics of a Savonius wind turbine.

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In recent years, for the purpose of optimizing the heat transfer and pressure drop characteristics, the CFD analysis method of finned tubes have been developed and the heat transfer coefficient distribution on a fin surface was revealed. However, there are few measured results because the heat transfer coefficient distribution can not be measured in detail by traditional steady-state method. In the present study, we introduced a new method which is non-contact, transient technique to measure the heat transfer coefficient distribution. Since conventional transient technique assumed a test model as a semi-infinite flat plate, error occurs when applying to the finite thickness flat plate. To resolve the problem, we applied the unsteady-heat-conduction equation in consideration of a fin thickness to evaluate a heat transfer coefficient. The measurement was carried out in the condition of Reynolds number Re=1.6×10^4. And the result was compared with the numerical analysis. We consider that this transient technique is also better to minimize a measuring period and cost than traditional steady-state measurement method which need finned tubes made by metals.

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To improve the power generation performance of Polymer Electrolyte Fuel Cell (PEFC), the operation at high temperature up to 90 ℃ is desired. To develop the PEFC system operated under high temperature condition, the heat and mass transfer characteristics should be clarified. The aim of this study is to clarify the heat and mass transfer characteristics in single cell of current PEFC using Nafion membrane under high temperature operation condition. By using thermograph, the in-plane temperature distributions on backside of gas separator of cell at anode and cathode under power generation were measured with changing initial operation temperature of cell, relative humidity and flow rate of supply gas. As a result, it is clarified that the heat and mass transfer characteristics in single cell of PEFC under high temperature operation conditions are different from those under the usual temperature operation conditions. To obtain the high power generation performance of PEFC using Nafion membrane at high temperature, the relative humidity of supply gas must be kept high.

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The OSAKI CoolGen Project is being implemented by OSAKI CoolGen Corporation, which was founded in July 2009 under joint funding by the Chugoku Electric Power Co., Inc. and Electric Power Development Co., Ltd. (J-POWER). This project aims to realize innovative low-carbon, coal-fired thermal power generation that combines an Integrated Coal Gasification Fuel Cell Combined Cycle (IGFC), an extremely efficient coal-fired thermal power generation technology, with CO_2 capture technologies, thus drastically reducing the CO_2 that is emitted from coal-fired thermal power generation. The demonstration project has been planned in three steps. The first step will implement demonstration tests of the Oxygen-Blown Integrated Coal Gasification Combined Cycle (IGCC), which is the base technology for IGFC. Towards the start of demonstration testing in FY 2016, civil work was started in March 2013 and equipment and electrical work was started in June 2014. In the second step, we plan to carry out demonstration testing of the oxygen-blown IGCC of the first step with a CO_2 capture unit added. In the third and final step, we plan to demonstrate an IGFC system combining the demonstration plant of the second step with a fuel cell. The following will explain the project outline, focused on the first step, which is the oxygen-blown IGCC demonstration project.

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Lignite, a low-rank coal, is characterized by low calorific value, mostly attributed to its considerable water content. Upgrading the quality of this energy carrier, which benefits coal-fired power plant's thermal efficiency, can be effectively realized by means of drying. The kinetics of superheated steam drying was studied for 30 mm spherical samples from Belchatow lignite mine in Poland. The experiment featured simultaneous and continuous measurements of weight and temperature. The drying kinetics, described by curves of moisture content, drying rate and temperature profile, were evaluated using the data acquired. The present study is a follow-up of analogical examination conducted on 5 and 10 mm objects from the same lignite deposit. The appearance of the sample throughout the process was video-recorded. Widespread cracking and shrinkage, which differ depending on the conditions, along with series of droplets typical for larger sample, were observed. The examined particles were suitable for predictions of thermodynamically derived drying rate and time, as proposed previously for smaller particles. However, in comparison they exhibit more uniform density distribution. Extensive investigation, revealing features of variously-sized samples as well as diameter dependence of drying behavior, is required for purposes of designing industrial drying system dedicated to specific type of coal.

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Coal is one of the important resources of electricity generation to maintain a stable supply of power. Although, it is the main contributor to the rise of energy-related CO_2 emission. According to "World Energy Outlook 2014", though electricity demand has increased in the Organization for Economic Co-operation and Development (OECD) and Non-OECD member countries, coal use will decrease toward 2040 in OECD. However, coal use in Non-OECD will increase up to about three times in 2040 as compared with 1990 (International Energy Agency (IEA), 2014). This is why, we need to reduce CO_2 emission from coal fired power plants in order to halt global warming. As a method of reducing CO_2 emission, we have carbon dioxide capture and storage (CCS) technologies. Oxyfuel combustion is one of the CCS technologies and IHI has developed it since 1989. Then, Callide Oxyfuel Project commenced to demonstrate oxyfuel power plant in March, 2012. During the demonstrated operation for approximately three years, many tests were conducted and many data were collected. As a result, we confirmed the difference between airfiring and oxyfiring such as operational flexibility, plant efficiency and combustion characteristics. In this paper, the operational results of 30MWe oxyfuel power plant in the Project are presented.

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Advanced Integrated coal Gasification Combined Cycle (A-IGCC) systems have been proposed to obtain higher power generation efficiency than IGCC systems by recycling the exhaust heat from a gas turbine as the heat source of the gasifier. To date, the A-IGCC system including gasification, gas treating including CO_2 capturing and combined cycle power generation units has not been designed. In this study, the performances of A-IGCC systems with these units were evaluated by using process simulator Aspen Plus[○!R] ver. 7.2. Results showed the net thermal efficiencies of A-IGCC models with water gas shift (WGS) and CO_2 capturing units were lower than that of models without these units by 3.5-5.2% because of reduction in gas turbine and steam turbine outputs and additional heat and electricity input to CO_2 capturing unit. Net thermal efficiency of the A-IGCC system with the hot gas desulfurization unit was higher than that with the cold gas desulfurization unit (CGDU) by 1.4-3.1% owing to decrease in heat loss in coolers at CGDU, subsequent increase of heating value of fuel gas into the gas turbine combustors. The CO_2 emission factor can be reduced from 744-769 kg-CO_2/MWh to 117-137 kg-CO_2/MWh by capturing of approximately 85% of CO_2 after WGS.

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Japanese iron and steel manufacturing industries import a significant amount expensive coking coal (coke); reduction of coke consumption is a great challenge for the industry. In this paper, we propose an in-plant CO recycling system which supplements coke with gaseous CO as a reducing agent in the blast furnace. Process flow diagrams including a blast furnace with CO recycling, coke oven, and hot blast stove were built in Aspen Plus and the effect of CO recycling on coal conservation, exergy efficiency, and CO_2 emission were quantitatively evaluated. In the blast furnace the input exergy, effective exergy ratio, overall CO_2 emissions, and the input coke decreased as the degree of CO circulation was increased. The recirculated CO gas was separated from the Blast Furnace Gas (BFG), the coke oven gas, and the converter gas. The separation and recycling of CO into the blast furnace resulted in the decrease of input coke, and input exergy by 13.0% and 10.3%, respectively. On the other hand, overall CO_2 emissions increased by 2.6%

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Natural convective flows around V-shaped cavities are encountered in some engineering applications such as over the heat-transfer plates or roofs having triangular-shaped grooves. In order to assess the heat transfer performance of these plates or roofs, detailed information on their flow and heat transfer will be needed. Therefore, the experimental investigations have been carried out on natural convection of water induced around a heated, V-shaped open cavity. The open angles, θ, and the side lengths, W/2, were varied systematically as θ = 90-180° and W/2 = 25, 50, 100 mm. The flows in the cavity and the surface temperatures were visualized with fine nylon particles and a thermos-chromic liquid crystal sheet, respectively. The results showed that the ambient fluid descends to the bottom edge of the cavity, and reach to the upper edge of cavity when θ<135°. The local heat transfer coefficients were also measured. The results showed that the heat transfer is enhanced markedly when θ = 120°. It is also found that the overall heat transfer coefficients from the cavity θ = 120° and W/2 = 25 mm became 17% higher than that from the horizontal plate.

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Ultrasonic pulsed Doppler method is a powerful tool to measure velocity distribution in a flow field. However, the method has the maximum measurable velocity. In addition, the measurement volume of this method is relatively large and it is known that the measurement volume affects measured velocities in near-wall region. To measure higher velocity, feedback method which is a dealiasing method and a multi-wave ultrasonic transducer were introduced. Using the transducer, velocities in the near-wall region were measured by 8 MHz ultrasonic with small sensor diameter, velocities far from the transducer were measured by 2 MHz ultrasonic with large sensor diameter. Thus, measurement volume was minimized in the near-wall region. Experiments were carried out at flow rate calibration facility at AIST, and the effects of the measurement volume and the number of pulse repetitions for obtaining an instantaneous velocity profile, N_<pulse>, was discussed. As a result, reduction of the measurement volume improved measurement accuracy in the near-wall region by using the multi-wave transducer, and the measurement accuracy of flow rate was improved. Increasing the N_<pulse> was found to be effective for improving the measurement accuracy even though the total echo signals are the same for calculating the average velocity distribution.

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A polymer electrolyte fuel cell (PEFC) generates electricity by the electrochemical reaction. It is well known that the water accumulation in the gas diffusion layer (GDL) reduces the cell performances. Hence, itis important to clarify the liquid water transport phenomenon in the PEFC. In this study, visualization of water transport phenomenon in an operating PEFC was carried out by using neutron radiography at Kyoto University Research Reactor (KUR). The two-dimensional water distributions in the through-plane of the membrane in the PEFC were compared between the experimental and the numerical results. The experimental results showed that more water accumulation was occurred in the GDL under the rib than that under the channel, and the analytical results could predict almost the same distributions in the GDL. It was found that the analytical results of water distributions were strongly influenced with the phase-change speed. Mole fraction of the vapor in the GDL under the rib was higher than that under the channel and it influenced the water accumulation in the GDL significantly.

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As global energy demand increases, improving energy security is one of the main issues of energy related problems in Japan. Thus the purpose of this paper is to evaluate energy security quantitatively and imply the best energy resource mix for the Japanese sustainable energy system from the perspective of energy security with considering an economic perspective. This study is mainly divided into three parts; conceptualizing energy security, evaluating energy security through international comparisons, and obtaining pareto optimal solutions by solving a multi-objective analysis considering energy security and economic feasibility. GAMS is used for coding the multi-objective analysis called an augmented ε-constraint method (AUGMECON). The results show that the Japanese energy system has improved from 2000 to 2010 from the aspect of both energy security and supply cost, however, it is still inferior to those of other countries. In order to improve energy security, the increase of the use of renewable energy and natural gas instead of oil and coal is recommended, therefore, it is an urgent task to establish a stable supply system using renewable energy and expand high resilient gas pipelines.

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Population and economic growth are expected to cause an increment of 37% in world energy demand by 2040 and 60% in food production by 2050. Simultaneously, rural population is abandoning farms, and cities are becoming mega cities. Therefore, a challenge of increasing agricultural land efficiency exists. Hence, a design of a multifunctional farm is proposed in this research, where food and energy is produced within farm boundaries. A linear programming model was developed with the objective of minimizing area, considering agricultural land and the area needed for energy technologies. A Business as Usual Scenario and another two were analysed. In Scenario 1 residues are feedstock of CHP and biofuel. Scenario 2 includes solar PV and wind turbines. A region in Japan was selected and compared with one in Colombia, in order to realise challenges for each. The results indicate that including different crops from the status quo could help achieving the goal of supplying high energy needs in less space; such is the example of cassava root in Japan for biofuel generation. If land use and crops are considered with the model proposed, biofuel production may not interfere with food security.

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In recent years, the increasing energy demands in the residential and commercial sector have resulted in increased carbon dioxide emissions (CO_2). In response, local authorities have proposed the compact city, a collection of business facilities such as a hospitals, hotels, offices and stores, with the intent to reduce energy consumption and improve the utilization efficiency of energy. Reducing energy consumption in business facilities is of critical importance, as urban areas continue the trend of concentration of people and services. In previous research, the evaluation of CO_2 emissions in the commercial sector was carried out using a combined system, composed of a micro-grid and district heating and cooling. The purpose of this research is to clarify the optimal combination of energy conversion technologies for each facility. A middle scale city in Japan that included 4 facilities (hospital, hotel, office, and store) was assumed, and 27 combinations of energy conversion technologies were evaluated. The objective function for optimization was installation and running costs. The combination of technologies was optimized to minimize the objective function. The optimization model was built using the GAMS/BARON solver. Comparing the results for each case, the optimal combinations were determined. The lowest the running costs for any facility type were achieved when photovoltaics, heat pump water heaters and turbo refrigerators were utilized.

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Biomass usually is noticed a composition of various types of waste materials that can be utilized as useful form of energy alternative to the conventional fossil fuels. However this new kind of energy hasn't met its full potential in production of energy especially electricity generation due to its lower performance in terms of thermal efficiency. Algae (included Microalgae & Macroalgae) is widely used for multi-application developments such as fishery aquaculture, food/nutrient supplement, cosmetics, and biomass energy. Microalgae has been treated as the source of bio-fuel. In this paper we selected the two type of freshwater microalgae "Chlorella Vulgaris" & "Spirulina" and macro algae (Laminariaceae) as the main materials and we analyzed TGA (Thermal Gravity Analysis) and calorific values (heat of combustion). We found the calorific values are 1000〜5000 KC/KG and TGA results show that the microalgae decrease rapidly after reached 300 ℃. The results in this paper will be used as a reference material for microalgae multi-oriental energy application and biomass composition proximate and ultimate research development in the future.

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From the viewpoint of energy security and global warming issues, highly efficient coal utilization system, such as the integrated coal gasification combined cycle (IGCC) power systems and chemical synthesis processes using coal gasification are increasing their market size. As one of the leading companies in the field of IGCC and coal gasification, Mitsubishi Hitachi Power Systems, Ltd. (MHPS) which jointly established by Mitsubishi Heavy Industries, Ltd. (MHI) and Hitachi, Ltd., and MHI are now in a position to build up market share. With an integration of two-stage entrained flow air-blown coal gasifier, the IGCC will achieve the highest net plant efficiency by using air as the gasification agent, and the F or G-class high temperature combustion turbine for power generation market. This paper includes discussions on the latest status of the 250MW Nakoso IGCC commercial plant and overview of 500 MW class plant integrated with the F or G-class high temperature gas turbine. This paper will also discuss about our latest activities on the oxygen-blown gasification systems for chemical synthesis and application to biomass and petroleum coke.

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Battery energy storage system (BESS) is expected to suppress fluctuation derived from increasing amount of renewable power generation, such as wind and solar. Depending on the variation to be suppressed, BESS capacity and their initial costs increase. We studied a method to realize fluctuation suppression for wind power BESS system. In this method, we developed control method using wind velocity and long period power variation of power grid in order to reduce BESS capacity. Sum of wind power and BESS output is supposed to be controlled in accordance with report of request for grid-interconnection with wind power. Using wind velocity and long period power variation values, power reference of BESS charge and discharge were calculated to settle proper state of energy of BESS by using measured single wind power system field data. As the result, comparing conventional without power control case and proposal case for BESS, in the case of proposal control, the BESS capacity can be decreased to 60% of rated wind power generator.

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This study deals with heat transfer performance of plate condenser used for heat pump water heater in the condition where the refrigerant as superheated vapor is cooled to a subcooling liquid with large subcooling. Since condensate liquid might affect the refrigerant flow distribution, the both effects of the wave height of plates and gravity were examined. The gravity effect was evaluated by the experiments for horizontal and vertical orientation. HFC-134a was used as the working fluid. In the results, a deterioration in heat transfer rate due to the maldistribution of refrigerant flow was observed. The amount of decrease became larger with the larger wave height of the corrugation. The tendency was larger for the horizontal orientation. In the results for plate heat exchanger with single refrigerant path, it was found that the condensing flow behavior for the horizontal orientation was strongly affected by the wave pattern of the corrugation, because the condensed liquid tended to flow along the wave pattern of the lower plate due to gravity. The flow behaviors might cause maldistribution of the refrigerant flow.

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Niigata University works in collaboration with AIST, YSEC, and companies in Niigata area to develop a compact jet engine for industrial unmanned aerial systems. The group work is called NIIGATA SKY PROJECT. The group aims to develop an environmentally friendly low-noise jet engine fueled by bio-oil. This paper describes two elementary tasks: (1) development of manufacturing skills for compact jet engine system; (2) experimental testing of Jatropha-oil-fueled compact jet engine. For the first task, the group successfully manufactured the NSP 3 jet engine that consists of a centrifugal compressor, an annular combustor, and an axial turbine. The design was made referring to the Netherlands-made engine. Over 90 percent of the engine parts were produced in Niigata area. The machining and assembly skills were nurtured and verified through tests using kerosene. The results demonstrated that engine has the capacity to output thrust of 10 kg or higher, comparable to the reference engine. For the second task, a US-made compact jet engine was tested using Jatropha-oil-mixed kerosene. This engine showed the capacity to work with the bio-oil mixture fuel at a maxim of 30% mixture rate. The engine fueled by the mixture oil emitted more carbon monoxide than the engine fueled by pure kerosene. However, the thrust of the mixture-oil-fueled engine differed only slightly from that of the pure-kerosene-fueled engine. The usefulness of the bio-oil mixture fuel was thus proved.

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Hydration reaction characteristics in a composite of calcium chloride and of silica microcapsules with holes have been investigated. Silica hollow microcapsules with holes with the diameter of 19.1 μm were fabricated by a double emulsion method and calcium chloride was installed inside the capsules. The including rate of calcium chloride in the capsules was 0.20. The observation of Silica hollow microcapsules by the scanning electron microscope was also performed. From the observation, the thickness of outer shell of microcapsules was 0.75 μm. From the results of hydration reaction experiments, it was found that the reaction rate is higher than that of the composite of calcium chloride and of expanded graphite. This was caused due to the high thermal conductivity of the present composite. It was also found that reacted water per volume is 2,000 times larger than the expanded graphite because the present capsules contains large amount of calcium chloride. Thus, the present composite is a promising item for realizing the chemical heat pumps.

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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). Specifically speaking, experiments are conducted with Cu/ZnO/Al_2O_3 catalyst. Using a household-use-scale reactor with well-controlled temperature distribution, the authors have shown that the Cu/ZnO/Al_2O_3 catalyst has rather high performance with high hydrogen concentration C_<H2> at low values of reaction temperature T_R. 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 upon the ethanol conversion X_<C2H5OH>, in a wide range of LHSV at several S/C's and at several T_R's. 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 CH_3CHO. Furthermore, the authors discuss the influences of T_R in addition to LHSV.

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A Computable General Equilibrium (CGE) model has been developed and applied to Japan in order to analyze the economic impacts caused by the introduction of bioethanol produced from rice. Even though the analysis is done on a national level, the application of the model is regional. That is, Japan has been divided into nine geographical regions, and the model has been applied to each. For each region, a Social Accounting Matrix (SAM) has been prepared to be used as database for calibration of the model. Then, the introduction of bioethanol is simulated as a substitution of a fixed share of the petroleum sector using a penetration rate parameter. The model is then run for a wide range of this penetration rate parameter (from 5% to 100%) with the intention to cover all the common ethanol fuel mixtures. Results show that the major economic impact of the bioethanol introduction is on the rice sector, where the feedstock of the bioethanol comes from. This sector experiences an increase linearly proportional to the bioethanol penetration rate in its demand and price. Also, a negative economic impact on the food sector is observed, as it presents a decrease in its level of production due to the deviation of the rice now used to produce ethanol.

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Carbonization of bio-dried sludge was conducted under different carbonization condition, and element analysis of sludge char was carried out. In this study, behavior of elements from bio-dried sludge to char during carbonization was revealed. In the experiment, lab-scale bath type reactor was used. In the lab-scale experiment, carbonization of bio-dried sludge was conducted in nitrogen or steam flow circumstance, and carbonization temperature and duration was changed. Elements of sludge char were analyzed after carbonization. The yield of carbon, hydrogen and nitrogen in bio-dried sludge decreased, as increasing carbonization temperature and extending duration. When carbonization duration was extended, yield of carbon and nitrogen decreased in the case of at low temperature. The yield of sulfur in bio-dried sludge decreased slowly against carbonization temperature, but it increased at high temperature over 973 K. Sulfur in bio-dried sludge was remained in sludge char not being decomposed. However sulfur content decreased at high temperature when steam was introduced during carbonization of bio-dried sludge.

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A thermoacoustic engine is one of external combustion engines and has a very simple structure. Thus, the engine can be a waste heat recovery device with low cost. To drive the engine, the heat source temperature is needed to be higher than the critical value. Recently, it was found that the critical value decreases when two-phase fluid is added into the working gas of the engine. However, the output power of the engine with two-phase fluid has not been experimentally investigated. In this paper, we measure the Q value and output power of the engine with and without two-phase fluid. The result of measurement of the Q value shows that the two-phase fluid does not contribute to the thermal and viscous energy loss and increases the acoustic power production. Therefore, it is considered that the reason why the critical value is reduced is the enhancement of energy conversion. When the temperature difference was 125℃, the measured output power of the engine with two-phase fluid was 0.4 W and the engine without two-phase fluid was not able to generate an acoustic power.

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This paper aims to design the woody biomass supply chain for co-firing in the coal power plant. The woody biomass supply chain consists of 4 processes; Collection, Resource transportation, Preprocessing, and Fuel transportation. Preprocessing is divided into two processes such as Drying and Fuel production. Sawmill residue, construction waste, forest residue, thinning residue, and pruning of fruit tree are treated as raw material. Wood chip, pellet, and torrefied pellet called black pellet are treated as bio-fuel. The transportation of raw material and bio-fuel is optimized by using Geographical information system (GIS). As a case study, the woody biomass supply chain in Tohoku region is designed. The potential of raw materials is 37 PJ/year, and the availability is 3.6 PJ/year. As all resource is utilized in power plant, the lowest amount of energy consumption is 0.9 PJ/year that the all raw material is consumed to produce the pellet in resource generation points. And the lowest cost is 40,000 JPY/t of black pellets that are produced in resource generation points. It is obtained that the drying process and raw material transportation are dominant on energy consumption and cost.

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In recent years, energy saving of the propulsion plant is progressing as environmental transformation which surround a LNG carrier. In addition to the conventional steam propulsion system, the medium-speed diesel engine in which the gas combustion which is superior in plant efficiency is possible is increasing. So, in our company, the reheat furnace which arranged the reheat burner was formed in the exhaust gas exit of the main boiler (with no reheat) of a conventional type as a boiler of a reheat system, and the structure which overheats reheat steam was developed by making a main boiler exhaust gas warm. Thereby, while forming steam temperature into high temperature and high pressure, it contributed to 15% of improvement in efficiency to the conventional steam propulsion plant by adopting a reheat cycle. At the running test in the real ocean space, these measures were able to prove the target performance of steam temperature.

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Powertrain electrification and lightweighting can lower light-duty vehicle (LDV) fleet energy consumption and CO_2 emissions. A stock turnover model of the LDV fleet is used to estimate the potential of powertrain electrification, lightweight materials use and vehicle size reduction for CO_2 emissions reduction and the impact on energy and automotive material use. 24 LDV types are considered, combining four powertrains, internal combustion engine vehicles (ICEVs), hybrid electric vehicles (HEVs), battery electric vehicles (BEVs), and fuel cell hybrid electric vehicles (FCHEVs); two glider types, conventional and lightweight; and three vehicle size classes, normal, compact and mini-sized vehicles. The case of Japan is studied, considering the base scenario and six alternative scenarios where HEVs, BEVs, FCHEVs, lightweight mini-sized HEVs, lightweight mini-sized BEVs and lightweight mini-sized FCHEVs are deployed. Compared to the 2050 baseline values of tank-to-wheel (TTW) energy consumption, 797 PJ/yr, and TTW CO_2 emissions, 53.1 Mt-CO_2/yr, maximum energy consumption and CO_2 emissions reductions of 563 PJ/yr and 49.0 Mt-CO_2/yr are obtained using lightweight mini-sized BEVs. Nevertheless, the largest energy consumption and CO_2 emissions reductions until 2029 and 2027 are achieved with lightweight mini-sized HEVs. Despite of aggressive lightweighting, iron and steel represent more than 30% of automotive material consumption by 2050.

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Recently, thermal power generation is increasing to compensate the stoppage of nuclear power plants in Japan. The steam turbines are used for thermal power plants and the importance is increasing as the core component of the power generation. The development for the A-USC(advanced ultra super critical) power plant is a very remarkable project to increase the efficiency of the power generation. Also the development to increase the efficiency of each element is important. This research is focused on the 3D design turbine blade and the method to further reduce the loss of the blades. The 3D blade loss is minimized by the optimum selection of 3D blade parameters and adopting 3D fence. The optimization is conducted by using CFD and experiment.

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Three-dimensional numerical calculations were performed on the magnetohydrodynamic (MHD) flow through a rectangular channel with sudden expansion. The sudden expansion is in the direction of the applied magnetic field. The continuity equation, the momentum equation and the induction equation, derived from Maxwell's equations and Ohm's law, were solved numerically. The discretization of the equations is carried out by the finite difference method, and the solution procedure follows the MAC method. A base case calculation was carried out for a Hartmann number of 100, a Reynolds number of 1000, a magnetic Reynolds number of 0.001, an aspect ratio of 1 and an expansion ratio of 2, simulating conditions typical to experimental scales and conditions. The loss coefficients for the expansions with aspect ratios larger than 1 or smaller than 1 become smaller than that in the base case (i.e. the aspect ratio of 1). A flow channel with a small aspect ratio has the advantage of decreasing the pressure drops both in the fully-developed flow and in the flow through the expansion. On the other hand, the loss coefficients for the expansions with expansion ratios larger than 3 become larger than that in the base case (i.e. the expansion ratio of 2).

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Breakup patterns splashed from a plate edge which is set in parallel air flows are observed by a high speed camera in a fundamental study on breakup of a water film. The experiments were done using air flows with maximum velocity of 127 m/s and water supplied by city water. Breakup patterns of the water film change with the Mach number of the air flows and the relative Weber number which is expressed by the water film thickness taken as the reference length. In the low Mach number region, droplet-type patterns appear. In the high Mach number region, sheet-type patterns are observed. In the mid Mach number region, droplet-type, string-type, thrown-net-type, and sheet-type breakup patterns can be seen. The thrown-net-type breakup pattern is a unique breakup pattern that is not observed in a single droplet breakup. When the relative Weber number increases, the transition to the sheet-type pattern begins earlier than that at the low relative Weber number. Water film breakup patterns can be classified on a map based on the Mach number and relative Weber number within the experimental ranges of this study. Some correlations between wave patterns on the surface of the water film and breakup patterns of the water film are also observed.

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Currently, due to advances in CFD technology, heat transfer analysis which took the time and effort has become easier by the coupled analysis of fluid-structure using CFD simulation (Conjugate Heat Transfer). Until now the verification of this analytical accuracy is not sufficient, firstly a large-scale experiments for verification were conducted. The measurements were carried out with high accuracy by the measuring apparatus and the performance of the fin and tube type heat exchanger was obtained. Secondly the one element of the test heat exchanger is analyzed by the CFD with solid fluid coupled analysis. The precise mesh was generated consist of primary and secondary fluid and of fin and tube solid. The accurate simulation for the heat exchanger was carried out and the heat transfer and pressure loss for each flow rate were determined. The experimental results and CFD results showed good agreement, especially in the large flow rate range.

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The purpose of this series of study is to clarify the effects of surface tension on vertical upward annular flows in a 5 mm I.D. pipe. Water and PLE (aqueous solution of a little surfactant, Polyoxyethylene Lauryl Ether, being about 40% lower surface tension than water) were used as the test liquid, while air as the test gas. Experimental data on mean liquid film thickness, liquid droplet fraction, interfacial shear stress and frictional pressure drop were obtained together with flow pictures. In these, frictional pressure drop is mainly discussed in the present paper. It is cleared that the frictional pressure drop is higher in the low surface tension case. The cause of this is considered to be due to rough interface between liquid film and gas core, high liquid droplet fraction, thin liquid film thickness and high interfacial shear stress, as reported in our previous paper. Thus, firstly, the main findings in our previous paper are briefly introduced. Secondary, pressure drop data have been presented and used to test correlations in literatures, and a new prediction method has been proposed by accounting for the surface tension effects.

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In order to solve EV issues, AI-EV (Air-conditioner Integrated Electric Vehicle) which is integrated with a power source for operating an air-conditioner and traveling a vehicle. In this paper, the authors have examined a method which decreases AI-EV energy consumption for air-conditioner by constructing a heat balance model between the air and the refrigerant at each heat exchanger. In addition, the effect of the air-conditioner performance on the cruising range of the AI-EV and CO_2 emissions when the AI-EV is introduced in the Smart PV and EV system has been evaluated. As a result, due to the improved heat transfer area of a condenser and the effective use of the engine exhaust heat, the COP (coefficient of performance) increased 1.4 times. It was determined that the annual CO_2 emissions are slight difference in the Smart PV and EV system through the use of the AI-EV. On the other hand, the cruising range of an AI-EV with the advanced air-conditioner mounted is able to be extended by more than 25 km in comparison with a conventional AI-EV.

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