In the present study, the authors conduct subsonic wind-tunnel experiments, in order to investigate the effect of the depth-to-width ratio λ on the tumbling of simple two-dimensional rectangular-cross-section prisms. The authors carry out instantaneous angle measurements of prisms' rotation, flow visualisation and velocity measurement using a hot-wire anemometer. As a result, there are two modes at λ<0.6 and λ>0.6. Atλ=0.3-0.5, main vortices are emitted during one rotation, and the cycle of velocity fluctuation is 360°. At λ=0.6-0.8, main four vortices are emitted during one rotation, and the cycle of velocity fluctuation is 180°. Especially, at λ=0.5, we can see transient features. At λ<0.6, momentum deficit Md increases with increasing λ. At λ>0.6, M_d decreases with increasing λ. Then, we can see the maximum of M_d at λ=0.6.

抄録全体を表示

This paper presents a study about an unusual horizontal axle wind turbine (HAWT). The shape of each blade is cylindrical. It obtains lift by forced boundary layer control, so this HAWT rotates. However, it does not have enough efficiency. One reason for this the study is still in an early stage of investigation. Therefore, as part of the improvement of its efficiency, this study tests a particular mechanism called "Centrifugal Vent (CV)". It is focused on not performance of the air foil, but rotation of the wind turbine. When the blades are hollow, the air at the tips of the rotating blades is pressured by centrifugal force. Therefore, this mechanism has a hole in each blade to vent out the air counter to the direction of lift in order to add momentum to rotation. As a result, wind tunnel tests show that CV improves torque as the numbers of rotations grow, and with that, power coefficient is up to double in this wind turbine. These effects vary by the method of intake air or the size of vent hole.

抄録全体を表示

The role of new energy has increased year by year to prevent the global warming crisis. Wind energy is one of the renewable energy. However, wind power has a weak point of large output fluctuation. Therefore we need some countermeasure for the grid connection of wind power generation. To overcome this weak point, the method of moderating the output fluctuation by charging and discharging the battery seems to be effective, and now in development process. Our company has developed a wind power generation system by optimizing wind power limitation system and battery energy storage system. In this thesis, we introduce the outline of our system and the result to moderate the output fluctuation that we investigated by the simulation using the data of the existing wind farm.

抄録全体を表示

Power output fluctuation of 2 MW-wind turbine-generator systems, which apply fixed speed operation and variable speed operation, under wind speed fluctuation is analyzed by numerical simulation. The fixed speed operation has two levels of operating rotational speeds in response to the wind speed. The variable speed operation has two operating modes : constant tip speed ratio operation at low wind speeds and constant speed operation at high wind speeds. For any operation method, the pitch angle is controlled to maintain the rated electric power output. The simulation result carried out by using an observed field wind data shows that the variable speed operation can reduce the power output fluctuations with both long and short periods as compared with the fixed speed operation due to rotational inertia of the rotor. Furthermore, the influence of the pitch angle control at high wind speeds on the power output fluctuations is revealed.

抄録全体を表示

We designed and installed the high efficiency solar air-conditioning system in our own office building (Tokyo Gas Co,. Ltd. Nakahara building). The main feature of the system is as follows. 1. High efficiency solar thermal collectors ware adopted (evacuated tube type). 2. The gas fired absorption chiller heater that can use the solar thermal energy effectively was adopted. 3. The energy-saving control system to utilize solar thermal energy efficiently and to decrease the electric power of the accessory such as pumps was introduced. The solar air-conditioning system started operation from April, 2009 and we will evaluate the operational condition of the system for one year afterwards. In this report, we introduce the outline of the design concept of the high efficiency solar air-conditioning system.

抄録全体を表示

This paper presents the individual experiment result of heat pump system with air source only and water heat source only. The controllable data which are the compressor room temperature for air source and the water inlet temperature to water evaporator for water heat source are varied from 15, 20, 30℃ and 20, 30, 40℃, respectively. With the air source only, the maximum COP can be achieved 4.3 when the inlet circulation water to solar collector was 15℃ and inlet circulation water from temperature control chamber was 20℃. With the water source only, the maximum COP can be achieved 4.72 when the inlet circulation water to solar collector was 25℃ and inlet circulation water from temperature control chamber was 20℃. The inlet water temperature setting to water evaporator (PV/T) and inlet water temperature to water condenser are significant influence to the COP performance. The ambient air temperature and solar radiation must be monitored intensively for automatic dual heat source applied.

抄録全体を表示

A room heating method using an air conditioner with a thermal storage floor heating system is proposed. The floor heating system is composed of 32 polyethylene tanks 672l capacity and vinyl tube of 200m in length under the floord (10 m^2). The water heated by solar heat pump flowed though the tube. The floor heating system performances using heat pump with and without PV are compared. The stored calorie of the evaporator decreased 15% by PV. On the case of the evaporator with PV, however, electricity consumption decrease by 14%. As a result, the COP of the system is kept constant. The obtained electric power is about a half of the compressor power consumption.

抄録全体を表示

For purpose of long-term energy storing of solar heat energy, an effect of volumetric capacity and insulation coefficient of a storage tank was investigated. To increase the storage capability of cylindrical storage tank, the inside of the tank was separated cylindrically into three parts by a partition plate, such as the first part, the second part and the third part, from a central axis of the storage tank, to prevent heat flow out from inside to outside of the tank. The results of the calculations are as follows : (1) On a normal single type storage tank without partition plate (H-type), even if decrement of insulation coefficient from 0.434 W/(m^2℃) to 0 W/(m^2℃), stored energy was increased only 6%. (2) On the separated storage tank, when feed water from a storage tank to lower part of temperature of a solar collector (A-type), increment of energy gain from 5.3 % to 25.2% was obtained and when returned hot water by collecting solar heat into the same temperature's part as that of a separated part (B-type), energy gains from 33.2 to 49.7% were increased in comparison of the single storage tank with the same volumetric capacity, through a year. (3) For a cumulative stored energy, on both A- and B-types, the increment of energy gain of 15.8 〜 32.4% were obtained in maximum.

抄録全体を表示

Generally, the specifications of PV modules are represented by nominal values on the panels of PV modules. We assumed that the rated values of PV modules are different to nominal values. It is necessary to analyze the nominal maximum output, the rated maximum power output and the power output of reconstructed string of PV Array installed on the roof of the building We studied the difference between the nominal maximum output and the rated maximum power output, dispersion of the maximum power output for PV arrays and proposed the constructing method of string of PV array. As a result, the rated maximum power output is 45W, 229W higher than the nominal maximum output for p-Si arrays and CIS arrays respectively. The maximum of power output of CIS array increased about 2.53% by the reconstructing method of string.

抄録全体を表示

In order to prevent the global warming, the emission of greenhouse gases must be reduced. In the public transportation, an electric bus is suitable for realizing this. However, it has not been used practically, because the weight of the battery is heavy. Therefore, it has been proposed that the bus is charged electric power intermittently in every bus stop. In addition, the charging electric power is generated from green energy. In this system, a boosting charge system is important, because the charge must be finished in the boarding and alighting hour of the passenger. In this study, the storage system in the bus stop, the supply equipment and the storage of the bus are designed, and the effectiveness is confirmed by the model experiment using an electric automobile of 1-passenger. In addition, the relation between Li-ion battery or capacitor and regeneration energy is also examined.

抄録全体を表示

In this study, the authors use an electric motorcycle with photovoltaic modules as an example of solar vehicles. It is a problem that solar irradiance is changing frequently and unequally while the motorcycle is running. We designed and made three different prototypes of photovoltaic power controller (MPPT ; maximum power point tracker). They use conventional algorithm of hill-climbing control method, and named 'mono-system', 'multi-system' and 'enhanced mono-system'. To evaluate these power controllers against changing irradiance, driving experiments under the shadow of trees have done on oval track; we discussed each efficiency of photovoltaic system.

抄録全体を表示

Compared to electric automobile, electric motorcycle is small and efficient vehicle for bringing single person or two people. However, to use electric motorcycle, there are few problems ; running distance of the motorcycle is not very long, its output is not very powerful. In this study, in order to extend running distance, we applied solar cells on the rooftop of the motorcycle. Solar cells are connected to the lead-acid storage battery. Running experiment on the flat ground was done at the speed of 20 km/h, under the fine weather in winter. As a result, the motorcycle with solar cells ran 42.8km. Running distance was achieved 27% longer than that of the motorcycle without solar cells. Moreover, we designed and made a prototype of the regeneration brake system for the motorcycle with EDLC. The electric power collected from the motor at the braking time was able to be stored electricity into EDLC, and the load of the lead-acid storage battery at the acceleration time was able to be reduced re-utilizing the electric power.

抄録全体を表示

The fluid force represents an important source in energy power. Renewable energy can be harvested from the flow using oscillated membranes composed of flexible piezoelectric device (PVDF). The deformation of PVDF caused by fluid force induces bending stresses that generate a voltage due to electrodes positioned on the surface of the materials. We designed several useful devices forced by the fluid force action at a characteristic wave motion and flow velocity and also showed some application for utilizing wave energy and uniform flow. We examined an advanced technology of electrical energy generated by fluid force using flexible piezoelectric. We also performed a numerical simulation of fluid structure interaction to evaluate relations between the deformation of PVDF caused by fluid force and electric power.

抄録全体を表示

A time has come to reflect on civilization blessed with convenient fossil fuels for the past 100years. Fossil fuels such as petroleum, coal, and natural gas have become limited resources. In addition, bad effects caused by excessive carbon dioxide (CO_2) have now begun destroying our global environment seriously. Since current living and economical standards depend strongly on fossil energy sources, it is necessary to realize a new society that utilizes biomass as a source of energy. In such background, we manufactured the practical Stirling engine using biomass fuels in 2005. And we proposed a unique co-generation system by the engine that uses woody biomass fuels. The co-generation system provided about 3kW of electricity and the heat from the system can be recovered and used in a number of ways for space and domestic water heating. The co-generation system is utilizes up to 45% of the system input energy in the form of electricity or heat. In this study, we tried to recover the waste heat of 43% by using a thermoelectric conversion module. And the Stirling cooler using electric power based woody biomass energy is tested in performance.

抄録全体を表示

This paper brought the performance prediction of a Solid Oxide Fuel Cell (SOFC) - Micro Gas Turbine (MGT) hybrid system using biogas fuel. Assuming biochemical process, it is noted that the biogas mainly consists of methane (CH_4) and carbon dioxide (CO_2). In the present study, the concentration of CH_4 was varied from 100% to 20%, where the one of CO_2 from 0% to 80%, in order to analyse the effect of CH_4 concentration on the electrical power generation of hybrid system. It was found that the efficiency of the hybrid system degraded with decreasing CH_4 concentration. Main reason of the efficiency drop was voltage drop, while the CH_4 concentration was diluted from 100% to 20%. Consequently, getting lower concentration of CH_4 degrades the electrical power generation in SOFC. Therefore it led the performance degradation of the hybrid system.

抄録全体を表示

It is known that water emulsified fuel has an effect of suppressing NOx and soot emissions. Simultaneously, it is said that saving of fuel is also possible. But it is not yet shown clearly what the reason is. In this study, we investigated the emission and heat transfer characteristics of the combustion gas of water emulsified fuel produced from heavy oil A for industrial boiler applications.

抄録全体を表示

Absorption type refrigerator is expected to use for the cogeneration because it can be driven by the wasted heat about 90℃. But rated operation is short time in the driving condition through the year. The reminder of the year, refrigerator is sometimes driven intermittently. Therefore, the intermitted driving simulation is needed for considering energy saving. In this study, simplified simulation models of the absorption type refrigerator are developed and intermitted driving simulation is carried out. And effect of intermitted driving on the cooling capacity and COP is examined. As a result of the simulation, under the case of intermitted driving, cooling capacity is varied and COP is almost constant.

抄録全体を表示

This paper proposes a new Rankine-type cycle for power generation from low temperature heat source such as waste heat and solar energy. The proposed cycle doesn't use a working fluid pump whose power consumption aggravates a net thermal efficiency of Rankine cycle. Instead of the pump, the cycle uses valves switching hot and cold source fluids in heat exchanger. Operating principle of the cycle was shown, and the experiment was performed by using an expansion valve which simulates turbine/expander. Liquid-vapor change was observed in the simulated turbine. And it was shown that the cycle can produce enthalpy difference between turbine inlet and outlet.

抄録全体を表示

Utilizing wasted heat is a important issue to reduce primary fuel consumption. Because wasted heat sources are located far from heat demand, it is required to transport thermal energy efficiently. The objective of this study is to investigate the performance of heat transportation and conversion based on absorption heat pump mechanism with ammonia-water as the working fluid experimentally. The test rig incorporates an external heat exchanger to cool high temperature weak solution from the generator in order to emulate transporting working fluid without thermal insulation. The experiment indicates the proposed system can transport thermal energy at ambient temperature and the function of heat transportation does not affect the efficiency of the cycle.

抄録全体を表示

The ammonia-water absorption heat pump utilizing waste heat is effective for energy saving. However, it is usual that the heat demand area is away from the heat supply area. Solution Transportation type Absorption system ; STA is one of the heat transportation technology. This system transfers ammonia refrigerant, strong and weak solutions from remote heat source side to heat demand side over long distance. In other words, thermal energy is converted into chemical potential and transferred to the other side. From simulation, it was found that STA worked with almost the same efficiency as conventional ammonia absorption heat pump.

抄録全体を表示

From the point of view of low global warming potential, 2,3,3,3 tetrafluoropropene (CF3CF=CH2 : HFO-1234yf) is expected as the new alternatives of CFC refrigerants. However no experimental data and correlation for this substance can be available. In this paper, the experimental data, correlations, and equation of state for HFO-1234yf measured by our group are summarized briefly. In addition, the newest saturation tables as well as pressure-enthalpy diagram of HFO-1234yf are shown calculated the equation of state formulated by our group. The COP for basic refrigeration cycle by using the HFO-1234yf is also discussed against the HFC refrigerants.

抄録全体を表示

As an environmentaly friendly refrigerant, hydrofluoroolefins (HFOs) are regarded as the promising alternative candidate. HFO 1234yf (2,3,3,3-tetrafluoropropene) is expected to alternate HFC 134a or CFC 12, since its GWP (global warming potential) is as low as other hydrocarbons. Although numbers of HFO 1234yf drop-in results for ready-made systems have been reported, essential thermodynamic properties for HFO 1234yf are not studied. In the present study, gas-phase PVT properties were measured by the double-sinker magnetic levitation densimeter which has great performance to measure fluid density at high-temperature and high-pressure conditions. As the preliminary data, 16 measured data are presented. Because of the impurity of available HFO 1234yf sample, relative uncertainty of the present data is about 0.5 %. A couple of available thermodynamic property models were employed to evaluate their reproducibility in gas-phase.

抄録全体を表示

Critical properties (critical temperature, T_c, critical pressure, P_c, and critical density, P_c) were measured for HFO-1234yf (CF_3CF=CH_2, 2,3,3,3,-tetrafluoropropene). The measurement principle is based on the visual-observation-method of the phase boundary and critical opalescence for the sample fluid. Sample pressure is directly measured by a pressure gauge placed in a temperature-controlled-thermostat, so that T_c and P_c can be easily determined by observing appearance or disappearance of the phase boundary and behavior of the critical opalescence. Volume of the sample cell was determined by measuring CO_2 under the conditions of T_c and P_c for HFO-1234yf, and then P_c was determined. We also measured saturated vapor pressure of HFO-1234yf from 303.15 K to 367.15 K, and formulated them as the Wagner's type vapor pressure equation.

抄録全体を表示

For the improvement of the coefficient of performance of heat exchangers, such as air-conditioners, showcases and unit coolers, under frosting conditions, a clarification of the frost deposition mechanism in a low-temperature environment is necessary. Therefore, frost properties were measured at temperatures below 0℃. The experimental results were analyzed and the calculation model of frost growth in low temperature environments were made. In the calculation model, the ice column growth model of Tao was used at the crystal growth period and Pick's low and Le Gall's model were used at the frost growth period. The experiments results and calculation results were compared, and they were corresponding well.

抄録全体を表示

In this paper, we investigated experimentally the growth of frost layer under natural convection to obtain effects of conditions related to air and cooling surface. We compared the results with numerical calculations, which are based on a non-homogeneous frost layer growth model and a homogeneous frost layer growth model used in the study of the forced convection. The comparison showed that the trend of the numerical results for a non-homogeneous frost layer growth model is in good agreement with the experimental results. The growth of the frost layer is markedly influenced by the thermal conductivity of the frost layer. The present numerical calculations suggest a thermal conductivity for the frost layer that is twice the value predicted by Yonko-Sepsy relationship. An accurate evaluation of the thermal conductivity of the frost layer is necessary to be able to match the frost layer thicknesses with those of the experiments. The present numerical model has the potential as a tool for the systematic investigation of influences of various factors affecting the frost phenomenon.

抄録全体を表示

The authors research the jet from a two-dimensional nozzle which has a lip-plate, especially concerning the effect of the lip-plate length of the nozzle. Experiments are conducted at a Reynolds number of 6000. The aspect ratio of the nozzle exit is 300, and the lip-plate length is 0,2h and 3.3h, where h denotes the height of the nozzle. Using a hot-wire anemometer, the authors show mean-velocity and turbulence-intensity profiles. And, using glycol smoke, the authors visualise the flow from the nozzle, and get quantitative information by a PIV technique.

抄録全体を表示

Growing of environmental concerns demands higher thermal efficiency for domestic gas cooking appliances. In this study, novel cooking appliance was proposed, and the prototype appliance was assembled. In addition, as the first stage, operating characteristics on an open mode was investigated. As the result, it was found that stable combustion was achieved at a wide operational range of a moderate heating power, while oscillating combustion occurred at an excessive heating power range. The behavior of the oscillating flame was also investigated in this experiment.

抄録全体を表示

Heat pumps using CO_2 as a natural refrigerant have been developed, and are expected to contribute to energy saving in domestic hot water supply. The objective of this paper is to analyze the performance of a CO_2 heat pump water heating system using a storage tank with a movable insulating plate by numerical simulation. A simulation model based on variable control volumes and a relevant solution method are proposed for this objective. A numerical study is conducted to compare the performance of the conventional and proposed systems. It is shown that the temperature in the middle part of the storage tank in the proposed system becomes higher than that in the conventional one, which reduces the volume occupied by water with middle temperatures. It is also shown that as a result, the performance of the proposed system is superior to that of the conventional one from the viewpoint of the trade-off relationship between the system efficiency and the volume of unused hot water.

抄録全体を表示

As for the current data center, IT equipment heat generation is increasing. Therefore, it is possible that the issue for IT equipment cooling cause. High heat generation of IT equipment that bring a big change in thermal environment in server rack. In some case, it may cause the failure of server, and it may cause an efficiency of IT equipment cooling decrease whole room. In this study, we evaluated the phenomenon by modeling of IT equipment cooling and laboratory experiments. And we evaluated the influence of thermal environment in server rack, by high heat generation of IT equipment and layout in the server rack. In this article, I would like to describe that the thermal environment in server rack and IT equipment cooling efficiency are affect by high heat generation of IT equipment. In addition, I would like to suggest the method of IT equipment cooling in data center in the future.

抄録全体を表示

In regards to data centers and telecommunication equipment rooms of recent years, the diversification of communication services has been accompanied by the tendency to install high heat density equipment in racks. As the result, air conditioning problems, including hot spot issues, are increasing. These problems are caused primarily by the exhaust air recirculation and the direct return of cool air to the air conditioners. Therefore, we suggest aisle capping method for high heat density equipment. This is to enclose the cold aisles or hot aisles of IT equipment. This is effective to suppress these two problems of airflow. This report presents the results of an experiment on the effects of improving the hot spots, energy-saving, and temperature-rise suppression during air-conditioner shut down in the case that each method is applied.

抄録全体を表示

Indices for rating operating efficiency in equipment have existed for some time, but the need for an accurate index based on actual operating conditions has recently been felt. The annual performance factor (APF) has been stipulated as a new efficiency index for office-oriented air-cooled packaged air conditioners, but no index yet exists for air conditioners in data centers that provide cooling year-round. This paper presents a detailed analysis of actual operating conditions of data-center air conditioners and proposes a new efficiency evaluation index for large-scale air conditioners in data centers.

抄録全体を表示

We investigated the cause of the air cooled packaged air-conditioner failure for the data centers. Possible associations between increased elapsed years of the air-conditioners, increased the failure rate and recovery time has been turned out Furthermore, we evaluated the reliability of the air-conditioning system using the field data The results showed that the minimum number of the reserve machines which the reliability of an air-conditioning system sustained under the elapsed years failure problem was two sets.

抄録全体を表示

Bio diesel fuel BDF is obtaining recognition in Japan as a renewable fuel which can be used as an alternative fuel without any modifications of diesel engine. We are making and testing BDFs made from an alcohol (methanol or ethanol) and waste edible oils (soybean, rapeseed, palm oils and beef tallow). The test quantities of the four BDFs (methyl and ethyl esters) were processed in a reactor, comparison of each fuel in engine performance and emission tests are reported in present paper. Specific conclusions of our study are ; 1) The four esters all have lower or similar levels of NOx concentration compared to #2 diesel fuel. 2) BDF made from ethanol and beef tallow has higher levels of CO concentration. 3) Bosch smoke degree decreased of 50% for vegetable ethyl ester compared to diesel oil at 75% load. 4) BDFs made from beef tallow and alcohol have proven to be a viable diesel fuel.

抄録全体を表示

In recent years, the heat island phenomenon is paid attention. The various method are studied as a heat island measure. Interlocking that at present, used various recycling material as one method to the road surface is developed. The interlocking block is being laid in the sidewalk and parking place. Interlocking that I used to this research can save a rain water into the block, from that is made with a an aperture material unlike usual interlocking. Also, a rain water is able to expect even the effect that easy to penetrate into a foundation and increase cultivation to subterranean water and cause the outflow to subterranean water security and drain controlled. Thereupon, I did examination about the temperature reduction effect by the difference of the specimen with this research.

抄録全体を表示

In recent years, the urban heat island to which the temperature of urban areas becomes high the shape of an island compared with the suburbs is regarded as questionable. As for this urban heat island, increase of urban population or energy consumed, the increase in Anthropogenic heat, etc. are considered as the cause. Now, subjects, such as LCC, are held although heat environmental measures, such as green roof, a green wall, Permeable paving, a Water retaining pavement, are studied. This research performed experimental research about the solar radiation shielding and the heat budget of a "reed screen" which are the natural vegetation recycling materials made from the reed which is a Water Purification Plants was performed, taking The viewpoint that a maintenance-free citizen participates easily by the viewpoint and low cost which use and preserve the natural features which the earth has into consideration.

抄録全体を表示

Many researches which noted controlling the heat island effect in recent years are done. As the cure method, rooftop gardening etc. attracts attention. However, it has many problems, such as execution cost and a maintenance cost. Then, we paid our attention to the "reed screen" which is a charge of a natural vegetation recycling material. The reed screen was able to be constructed to building roof concrete, and the following effectiveness was able to be acquired by conducting an observation experiment. In the summer, the rise of the concrete surface temperature was controlled by the reed screen and the natural wind.

抄録全体を表示

In this paper, our numerical simulation methods using the assumption of the linear relation between solid volume fraction and temperature, and considering the hysteresis in melting and freezing were validated by comparing with the results of one-dimensional unsteady heat conduction experiment using composite materials of silicon gum and Micro Encapsulated Phase Change Materials (MEPCM) 30wt%. As a result, the impact of how to measure melting / freezing point and heating / cooling rate in DSC (Differential Scanning Calorimetry) on the accuracy of numerical simulation were demonstrated quantitatively.

抄録全体を表示

Recently, lithium-ion cell with large capacity that can be applicable for industrial usages such as backup batteries for power systems has been developed. The lithium-ion cells are expected to reduce the space of the back up battery system drastically. In the backup applications, long service life as well as cell safety is required. Therefore, to improve the safety of the cell, we have prepared a separator that has higher endurance-temperature than conventional polyolefm separator and evaluated the effect on the cell performance. Moreover, a cell structure that has a heat conductor inside the cell was proposed, and the effect of the heat conductor on the characteristics of the cell in overcharge was verified by using a lithium-ion cell with rated capacity of 40 Ah. As a result, it was confirmed that improvement of the endurance-temperature of separator and installation of the heat conductor was effective for the improvement of the safety of the lithium-ion cell.

抄録全体を表示

Today, lead-acid batteries are the most common choice for battery backup of communication equipment power systems. In recent years, however, a demand for a more compact power supply is growing amid expectations for spreading use of the NGN. Lithium ion batteries, which feature high energy density, are expected to greatly contribute to such reduction of power supply size. Improved safety and longer lifetime are indispensable for use of lithium ion batteries in power supply facilities for communication equipment. When manganese-based active material is used for the positive material, manganese eluted from the positive electrode migrates to the negative electrode surface, where it reacts with lithium ions to deactivate the lithium. That phenomenon has been confirmed to decrease battery capacity. Therefore, to extend battery life, we investigated the elution characteristics of manganese ions from the positive electrode by using test samples in which the elemental manganese of the positive material is partially replaced with some other metal element. The results show that there is least elution of manganese from the positive electrodes of lithium ion batteries that use manganese-based positive materials when the manganese is replaced by magnesium. With the objective of higher battery safety, we also investigated the elution characteristics of manganese ions from the positive electrode for when a phosphazene-based flame retardant has added to the electrolyte solution. The results show that the flame retardant in electrolyte decomposes during long-term storage to generate fluorine compounds, which have been confirmed to accelerate the elution of manganese ions. We also learned that decomposition of the flame retardant is related to the stability of the electrolyte, so elution of the manganese ion can be controlled by using a stable electrolyte.

抄録全体を表示

Flow characteristics of ice slurry in narrow tubes were investigated experimentally. IFF, velocity of the ice slurry and diameter of the tubes were varied as the parameters, and measurements of pressure drop were carried out. As a result, in laminar flow region, the coefficient of pipe friction increased with the IFF. In turbulent flow region, the effects of the IFF on the coefficient of pipe friction were not significant in the case of small IFF. On the other hand, in the case of large IFF, the coefficient of pipe friction increased with the IFF. Moreover, the flow characteristics can be clarified using apparent Re number, which is decided by considering the ice slurry as pseudoplastic fluid.

抄録全体を表示

We proposed the Totalized Hydrogen Energy Utilization System (THEUS) for applying to commercial buildings. By introducing this system in actual fields, we have realized the simultaneously effective uses of electricity, hydrogen and heat, hi this paper, we reported energy efficiency evaluation of the system by the calculation. Data as heat demand for seven type buildings were used, including buildings with different scales, applications, and characteristics of heat load. In comparison with an ice storage system, it has been proved that the hydrogen system has the advantage of 9-17% in terms of effective energy use. Moreover, the flexible operation of metal hydride tanks for fluctuating heat demand of the building was evaluated.

抄録全体を表示

The growing attention to environmental problems, manufacturers to take into consideration the environment requires in their manufacturing activity. With the increase in the aged population, Japan has entered the aged society that calls for the necessity of mobility equipment designed for assisting the elderly. However, the existing electric wheelchairs do not meet the above demand due to lengthy recharging time and unsatisfactory running time. So, we developed power-saving and light-weight next generation electric wheelchair that can be driven by the fuel cell system. Prototype electric wheelchair was made according to the test results, and after repeated modification and improvement an electric wheelchair as an universal mobility was completed. In the process, we surveyed users regarding the wheelchair design and the concept of "progress," had them test drive the wheelchair, and reflected the results in our manufacturing.

抄録全体を表示

Recently, low pollution and reducing the fuel cost the car are requested because of the negative environmental impact decrease in the transportation section. Especially, the severity increases to the restriction of the car in the city part every year. Then, it aims to turn super-light, small car ULV (Ultra Lightweight Vehicle) to practical use as a small commuter car in the city part that authors have developed, to describe the improvement and the evaluation, to do the car sharing etc., and to propose it as a mobility equipment corresponding to future urban traffic in research. In this paper we focus on basic understanding of vehicle performance and considering Multi-PM ULV adapted to the local characteristics.

抄録全体を表示

Recent years, global environmental problems have become aggravated, and various energy-saving functions and methods been introduced in vending machines. However, it is reported that useless energy is consumed because the amount of power consumption changes greatly by the installation environment in actual operation. We aim to improve over concentration of vending machines by considering demands, conveniences, and environmental impact of vending machines. In this study, we demonstrated the system in operation around the place for Japan, monitoring the operating status of the vending machine. And, create a new formula to predict the power consumption of the vending machine considering the regional differences based on the data stored in various parts of Japan, and more accurate.

抄録全体を表示

Cooling control, called peak shift (PS) and peak cut (PC), for a beverage vending machine is carried out to reduce the electricity consumption around noon on summer weekdays. It helps reduce the electricity demand on power generation systems. In conventional PS/PC control methods, complex algorithms are needed to control PC start temperature inside the vending machine, or the temperature depends on the driving frequency of the cooling device. In this paper, a highly practical PS/PC control algorithm is proposed for a beverage vending machine. The algorithm extends PC time and proposes an optimum PS start time. The effectiveness is confirmed by a field-test.

抄録全体を表示

In order to use thermal energy effectively by applying the Cluster Energy Management System (CEMS) to universities, estimating the energy demand in universities is studied. For combining plural campuses from the CEMS viewpoint, dynamic demands of electricity and thermal energy including heating and cooling are needed. Large capacity cogeneration systems (COS) would be placed at the campus where the largest thermal energy demand is requested. To operate the CGS at nominal condition for appropriate time period, the information on dynamic demand amount of thermal-energy existing in the campus as well as the information on when and what amount electricity to be transferred to other campuses are required. To develop the demand model, the existing capacities of air-conditioning systems and power facilities in campuses and the dynamic change in demand depending on the ambient temperature, time period of use, capacity of the number of students, etc. are needed. For developing the energy demand model in universities, we study on the relation between thermal energy demands, ambient temperatures of five campuses of Keio University.

抄録全体を表示

A new estimation method for energy consumption by air-conditioning system setting in residential house is proposed. The estimated energy consumption is valuated by comparing with the actual data obtained in the project of Architectural Institute of Japan (AIJ) and the estimated values based on the standards of Japan Refrigeration and Air Conditioning Industry Association (JRAIR). For estimating the energy consumption, a proportionality factor of "a" between outdoor temperature and cooling load was introduced. Determination of a was carefully assessed by three different ways for existing eight air-conditioners. One method is the determination from the actual power consumption of existing equipment by using the COP based on a full cooling load at nominal condition of outside temperature being 35℃ and indoor temperature being 27℃ with the wet-bulb temperature of 19℃. Another way is the determination from actual power consumptions by using the COP obtained from the full and the half cooling loads. And the last method is the determination based on the nominal COP presented in the catalogue. Moreover, two different ways of determining a were compared. One is the determination at the fixed room temperature being the nominal condition. Another is the determination by considering the actual room temperature at different outdoor temperature. Finally, among the eight air-conditioning systems, the best result is obtained in the determination of a by determining from actual power consumptions using the COP obtained from the full and the half cooling loads under the fixed room temperature condition.

抄録全体を表示

The domestic energy consumption of household sector keeps increasing. Moreover, the style of residential houses is diversified into various kinds. The objective of this study is to propose the optimum method of energy consumption on residential houses. Therefore, we developed and verified the demand model of residential energy consumption. The behavior of energy demand and consumption on complex houses and residential houses reflects the variation in the dynamic behavior of residents. To express such behavior, we used the Monte Carlo method that is a kind of random variate generation method. In addition, the object model contains the demand model and device model to generate the energy demand and consumption. Using this model, we calculated the energy consumption per household around Japan. Accordingly, season variation, regional difference, and difference by the way of building a house could be expressed in this demand model.

抄録全体を表示

In order to reduce primary energy consumption and CO_2 emission, optimizing energy utilization systems in terms of the effective utilization of thermal energy, is an unavoidable process. A new energy management system is proposed by simulating energy utilization within Keio University campuses. Cogeneration systems (CGS) can operate at the nominal load with the maximum utilization of exhaust heat, and the electricity can be utilized by the network among five Keio University campuses. This system creates to utilize thermal energy with high level from second-law view-point and to contribute the electric-load leveling. The optimized energy-utilization system can be brought to realization by combining appropriate energy-demand units with a win-win relationship, which we call "Cluster Energy Management System (CEMS)". The CEMS was applied to five Keio University campuses in this report. As a result, the annual primary energy consumption of the five campuses could be reduced by 14 %, and the annual CO_2 emission could be reduced by 19 %, if the optimum CGS would be installed at Shinanomachi Campus, whose energy consumption account for a half of the five campuses. In addition, by surplus electricity from the CGS in Shinanomachi Campus to be shared within other Campuses, the primary energy consumption of five campuses could be reduced by 17 %, and the CO_2 emission could be reduced by 24 %.

抄録全体を表示

The water spray humidifying systems are now widely used to save energy in large scale dean rooms. Appling these systems to operational dean rooms, we must appraise how long the distance of vapor absorption is needed. The distance is determined many factors, such as temperature, humidity, air velocity, turbulent unit, water droplet diameter and mist density, and it is not clarified how the vapor absorption distance is calculated by such factors. In this paper, we clarify the distance under general electronics devices dean room atmosphere.

抄録全体を表示