Recently, the bio-ethanol for blend into the gasoline has been focused in order to reduce greenhouse gas emissions. For economical ethanol production using enzymatic hydrolysis and fermentation, the developments of a high concentration saccharification process using a little enzyme and the entire saccharide collecting process from residue after saccharification were demanded. In this study, the saccharificaton using milled sample of Japanese cedar and a solids-liquid separation by the filter press using the residue after saccharificaton were carried out. As a result, the enzyme, one tenth of sample content, maximized the saccharificaiton ratio in case of 2% sample content. The 5% sample content maintained a maximum saccharification ratio. The solid residue collected by the filter-press converted breakdown particles of the sample. And also the solid residue converted breakdown particles in cleaning by pure water.

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Aquaponics is a combination term of aquaculture and hydroponics and is the simultaneous production system of fish and vegetables without wastewater. In aquaculture, the water quickly becomes nutrient rich due to the fish digesting their food and excreting waste. In hydroponics, nutrient solution is required for growing plants. In aquaponics, the fish waste provides a food source for the growing plants and the plants provide a natural filter for the fish. This creates a small ecosystem where both plants and fish can thrive. In this study, for the development of a small aquaponics system which is enjoyable in a home or a school classroom, the completion of nitrification cycle and the adjustment of pH and ions in a short period were tried. The effect of microelements to the hydroponics also has been studied in the operation of aquaponics system.

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The burning process of micro PET particles is observed, when they are supplied into a sinusoidally oscillating lean propane-air premixed flame. Since PET particles follow the gas flow out of phase and produce relative velocity due to the difference in inertia force, effects of the relative velocity on the flame patterns in PET particle combustion can be systematically examined. The velocity vector fields of hot combustion gas are conditionally measured with a PIV system, whereas the velocities of objective PET particles are measured with a PTV system. It can be certified that, when a PET particle flies faster than the ambient gas flow, a long thin envelop flame tailed to the upstream direction is formed behind it, and that the boundary of the thin envelop flame transforms into a regular cluster of brilliant spots having diameters of several microns in the final stage of PET particle combustion.

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This paper describes erosion phenomena and measures in wooden wastes recycle-plant. As the Law for The Promotion of Utilization of Recyclable Resources was enforced with a view to resolving issues on resources and environment, various recycling plants have been operated. However, in the process of treating chips smashed for reproduction, repeated impingement of chips against blower's impellers and bends causes erosion, a serious problem. We make a report on erosion in recycling plants where wooden wastes can be reproduced into a particleboard, and on the influence of the impingement angle and velocity of chips upon erosion. On the eroded surfaces of impeller, a series of ripple patterns which of perpendicular to the impingement direction of chips is found.

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Salt Recycling Research Society has been studying the reutilization method of the salt byproduct generated from the waste treatment process since its foundation in 2003. Currently, we conducted the research work on the production of the eco-sodium hypochlorite (NaClO+KClO) by the electrolysis method without membrane from the saline water using several salt byproducts, which were recovered from the dechlorination process both in the landfill leachate treatment and the flue gas treatment of the waste incinerator. The eco-sodium hypochlorite can be utilized as the disinfectant in the sewage treatment plant and can be one of the important solutions of the salt byproduct reutilization. From the electrolysis test result using 3% saline water, we confirmed the production of eco-sodium hypochlorite with concentration of 1,000 to 2,500 mg/l.

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Micro scale pelletized RDF (Refuse derived fuel) gasifier using the superheated steam as gasifying agent was developed and the feasibility of the syngas as fuel for micro co-generation was verified. The thermal cracking experiment of wood was conducted at 500 to 700 degrees C. Syngas was analyzed and char and tars content were determined and analyzed. Moisture and tar in syngas were removed by a cooling device kept at 0 degree C. The calorific value of syngas was about 14 MJ, and was about 1/3 of town gas. Then, refining gas was supplied as fuel of a micro gas engine of 1 kW of outputs. And the production of electricity using the micro gas engine was measured. It experimented by changing the mixture ratio of syngas and town gas. As a result, it turned out that the mixture ratio of syngas is 13% possible for rated operation. Moreover, it compared with the simulation result. Furthermore, it investigated theoretically also about the feasibility as fuel for molten carbonate fuel cell.

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Micro scale RDF gasifier in which the superheated steam is used as gasifying agent was developed and the feasibility of the syngas as fuel for micro co-generation was verified. The thermal cracking experiment of RDF was conducted with the temperature range from 500 to 700 degrees C. Then the gasification experiments of the RDF were carried out with a bench scale reactor of the packed-bed type. Furthermore, the heat and mass transfer analysis model of the system was constructed and examined. From both the experimental and theoretical work, first, the pyrolysis characteristics of the RDF within the temperature range from 573 K to 853 K were revealed. Moreover, the production rates of pyrolysis gas under different experiment condition of superheated steam were determined and compared with the calculation results. And the ingredient of the pyrolysis gas was analyzed. After all, the pyrolysis gas which is generated from the RDF by thermal cracking was showed that it can fully use as gas fuel.

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Catalytic steam reforming of pyrolysis tar has been investigated using benzene and n-Heptane as model tar compounds. The effects of temperature, steam-to-carbon ratio (S/C) and weight hourly space velocity (WHSV) on the reforming reaction were clarified for each model compound. The commercial ruthenium-based catalyst was used. This catalyst is more active than the nickel-based catalyst and can suppress carbon deposition at the low S/C ratio. The two tar model compounds had different reaction rates. The product gas composition and yield vary with reformer temperature, S/C and WHSV. The carbon conversion rate increased with raising the temperature and decreasing WHSV. On the other hand, the change of S/C ratio little affected the carbon conversion rate. Benzene was more difficult to be reformed than n-Heptane. In the experiment performed at 800 ℃, S/C=3, WHSV=0.095 h^<-1>and model compound = n-Heptane, the results were that 12.6 mol/mol-Heptane for hydrogen yield and 88.4 % for the carbon conversion.

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This paper reports on the results of the investigation of tar removal by combination of reforming and adsorption processes. Tar was produced from chicken manure pyrolysis at the pyrolysis temperature of 700 ℃. Chicken manure contains 5.2% nitrogen by weight (dry base) which is about tenfold or much higher than conventional woody biomass that promotes formation of the tar-N (nitrogen heterocyclic compounds) together with the tar-C (aromatic compounds). The experimental results demonstrated that the tar-N was decomposed completely with the high reforming temperature of 900 ℃, but the tar-C increased when we increased the reforming temperature from 800 ℃ to 900 ℃. That is, the reforming process is not enough to remove sufficient amount of tar, especially tar-C. Therefore, the adsorption bed was installed downstream of the reformer in order to remove tar remaining after the reforming process. Activated carbon and wood chips were selected to demonstrate their adsorption ability for not only tar-C but also for tar-N.

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In recent years, export of resources such as plastic waste, iron, aluminum and copper scrap etc. are increasing in Japan under the background of economic development in Asia, while exported resources sometimes are processed improperly in developing countries that breed environmental pollution. Therefore, an appropriate physical distribution management system with traceability for the resources is necessary. This paper attempts to build a model of International Resource Recycling System using Information Technology such as Global Position System (GPS), Radio Frequency Identification (RFID) tags, etc. between Japan and China by means of an international accepted traceability system. As a fundamental research, we surveyed the present condition of recycling and landfill facilities and the popularizations of information technology such as internet, RFID tags, etc. in China. We also did a demonstration test between Japan and China in order to confirm the effectiveness of the wide-area recycling system. As a result, the International Resource Recycling System with traceability is proposed.

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In a pyrolysis gasification and reforming process of waste and biomass at low temperature of about 700 ℃, high concentration hydrocarbons in the gas and tar are formed. Therefore, by using hydrogenation catalysts, the method for efficiently reducing benzene and other lower hydrocarbons included in the reformed gas was examined by experiment using model gas. It became clear that all of benzene converted into methane at the temperature range of about 250-300℃ under the steam existence, lower hydrocarbons (ethylene, ethane and propylene) were also converted into methane. In the system coexisted with benzene and lower hydrocarbon, all of them converted into methane at 300 ℃.

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Ash melting technology has been introduced into municipal solid waste (MSW) treatment systems to satisfy the new regulations on Dioxins and the growing shortage of landfill site since 1990's in Japan. Authors have developed MSW gasification and melting furnace technology by combination of fluidized-bed MSW incinerator and swirling-flow ash melting furnace. In the melting furnace, minimum burner flame had been kept to ensure ignition and combustion of pyrolysis gas, even if the heating value and temperature of the gas varies with change of waste quality. Authors have developed a new on-line measuring system to monitor whether the pyrolysis gas can be ignited and combusted in the melting furnace. This system is installed in Aki Clean Center, and keeping burner flame is not necessary with this system. As the result, fuel consumption is reduced by 80% from that of that of conventional operation.

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Vitrification tests of asbestos wastes were carried out with a high-temperature gasifying and direct melting furnace developed by JFE Engineering Corporation. The asbestos wastes, such as sprayed-on asbestos and thermal insulation material, were vitrified with industrial and municipal wastes. The asbestos in the wastes is decomposed into oxides, which have relatively high melting points and vitrified into the slag in the furnace. It is confirmed that the asbestos fibers do not remain in the molten slag obtained by high-temperature melting, and the levels of asbestos in the emission gas samples were sufficiently low. Treatment of asbestos wastes in the high-temperature gasifying and direct melting furnace is proved to be a sufficient process to convert them into non-hazardous material.

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The proposed technology is a new concept that aims at energy-efficient drying and cleanup for general purposes by the use of liquefied DME (dimethyl ether) gas This technology reduces the energy required for water-removal to half the latent heat of water We removed almost perfectly water, other oily materials and PCBs-contaminated sediment by using DME. DME was completely recycled and none of it remained in these materials. Ground pollution is a significant environmental concern. However, large amounts of energy are required for the cleanup of the ground since the water contained in the soil and the sediment hinder the extraction processes that use hydrophobic organic solvents. Therefore, we focus on the use of liquiefied DME, which is eco-friendly, as an extractant. The saturated pressure of DME is moderate-0.51 MPa at 20℃. Liquefied DME resolves high volume organic contaminants and water. Moreover, water can be easily separated from DME by flash distillation.

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Teshima waste management project is going forward under the idea called the KYOSO. From this idea, it is important that information sharing of environmental efficiency and economic efficiency of business of the project between an enterprise, inhabitants, citizens. Therefore we compared it in the year of LCA / LCC of the project When it compared an evaluation result of 2004 and 2005 and 2006, the consumption of the heavy oil which was fuel increased for deterioration of the melting furnace, and it became clear that environmental load / costs increased together. In addition, as a result of LCA / LCC which assumed repair work of melting furnace, we were able to show the effect.

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Teshima waste treatment project is going forward under the idea called the KYOSO. From this idea, it is important that information sharing of progress of the project among an enterprise, inhabitants, citizens. Therefore we deliberated visualization the disposal place by 3D modeling that created periodical GPS surveying. By results data that surveyed by GPS of three years, we were able to confirm visually progress of the digging. In addition, we could compare actual condition of disposal place to future plans. Furthermore, we calculated a digging volume from a 3D modeling to assure strictness of the information and compared it with quantity of export. As a result, we were able to get fixed consistency.

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Recently, the problem of aging and depopulation has become aggravated in the solitary island To improve these problems, it is important to excavate the charm of the island and sending these. There are two systems that followed the idea of KYOSO that means co- create. One of the system that we developed is KYOSO green- map system. that does the charm and the culture of the island in the mapping. Another one is a landscape assessment system. This is a method that assesses the charm of the island quantitatively and proposes improvements. It examined for four students of WASEDA University and four foreign students, and showed the effectiveness ofthis system. We propose the improvement for TESHIMA island by landscape assessment system

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As the quality of garbage began to change and request of safety technology to waste disposal facility, disposal facilities had to become increasingly more complex systems. It became more difficult to maintain good designs and operations for disposal system. The number of accidents and other types of hazards were happening more frequently. The aim of this study was to construct systems that will make disposal facilities safe and more secure. We construct database called ATHDB-all collected about 3200 examples. Using this we constructed ATHDB of two facilities by information which each facility collected. The information collected by each facility have much information. The trouble has been described small blockage etc.... We propose how to use ATHDB. The use we proposed is the use with level such as managers and operator.

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As the quality of garbage began to change and request of safety technology to waste disposal facility, disposal facilities had to become increasingly more complex systems. It became more difficult to maintain good designs and operations for disposal system. The number of accidents and other types of hazards were happening more frequently. The aim of this study was to construct systems that will make disposal facilities safe and more secure. We developed APT (Accident Prevention Training tool) that trains the skill to operators. This tool was made with Virtual Reality technology. The concept of this tool were to show the manual in animation and support the education on the site. In this report, we show the improvement of WEIVS and the development of new tool by Second Life and use APT in two facilities. As the result we showed effectiveness of APT by trying by operators.

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As the quality of garbage began to change and request of safety technology to waste disposal facility, disposal facilities had to become increasingly more complex systems. It became more difficult to maintain good designs and operations for disposal system. The number of accidents and other types of hazards were happening more frequently. The aim of this study was to construct systems that will make disposal facilities safe and more secure. It is important to manage the trend of operation on the facility. We developed the management system of operation referring to precedent case "TESHIMA WASETE TREATMENT PROJECT". The feature of our system was use of information efficiently acquired by ICT (Information Communication Technology). In this report, we show the target management system at TESHIMA PROJECT.

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To construct the Sustainable Society, the importance of consideration to 3R (Reduce , Reuse, Recycle) in the design phase increases in various industrial products. Concerning Reuse and Recycle, the improvement of the disassembly property is important. Then we develop the quantity disassembly property assessment method Disassembly Property Index (DPI), one of the DfE (Design for Environment) supporting tool. Additionally, the quantitative environmental load assessment is also necessary to achieve the sustainable society. Though various LCA (Life Cycle Assessment) method is developed for such a demand, it is pointed out that there are a lot of problems in existing LCA. To solve such problems, Eco-Efficiency Potential Assessment (E2-PA) is developed. E2-PA is based on the concept of "Eco-Efficiency" and the "Potential Assessment". In this paper, we pay attention to small-size home appliances and mobile telephones. Recently, mobile telephones are produced and wasted in large quantities, therefore, it is hoped to be recycled. Then, we examine the consideration of 3R and environmental load assessment about them.

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At the university, some students have caused several accidents. Most injured parts by accidents that we investigate by hearing to some university were hands and fingers. We also construct database of accidents that happened at university. And almost the reasons of accident were due to a human error like inexperienced work at experimentation etc. The safety education and training to students is important, and that is the most effective to support the sense of crisis to prevent these accidents. The concept of bodily sensation-type supporting system for operators education was safety and can use anywhere and anytime. We showed the effectiveness of the system by examination.

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In this research, we have developed the BAS software which is based on LCA and LCC as an effective assessment tool for the planning and improvement of municipal waste management system. First, we inquired the municipality for effective uses of the BAS software. Then, not only ELP (Environmental Load Point), our the original environmental impact index, we incorporated some individual indexes, like CO_2 emission, landfill amount, material recycling rate, that corresponded to the guideline of Ministry of the Environment in BAS software. Secondly, we examined the effect of wide range waste management system as an example of BAS software. As a result, the melting treatment method could be introduced while holding expenses down.

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Environmental problems worsens, and a change of a personal lifestyle is demanded. In this study, we suggest LSA (Life Style Assessment) as technique to evaluate environmental load quantitatively of a lifestyle by applying LCA (Life Cycle Assessment) method, and aimed at performing examination to contribute to advancement and the spread of the methods. In this report, we take it up about development of LSA software to calculate environmental load easily of the whole lifestyle. We are able to have come to grasp environmental load of the whole life for of fixed-quantity and sight by using this software. Furthermore, we examine the application of the software.

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The NO_x aftertreatment system, using nonthermal plasma (NTP) reduction and NO_x recirculation, is investigated. A pilot-scale system is applied to a stationary diesel engine generator. In this system, NO_x is first removed by adsorption, and subsequently, the adsorbent is regenerated by thermal desorption using the waste heat of the exhaust gas. The desorbed NO_x is reduced by nitrogen NTP. Moreover, ambient air is introduced into the adsorption chamber with the help of the engine intake to recirculate the NO_x. The recirculation of NO_x also contributes to a reduction of the NO_x emission. In the present experiment, approximately 55% of the NO_x of the diesel exhaust (NO_x: 270-325 ppm, flow rate = 300 NL/min) can be continuously treated for 55 h. The energy efficiency of the system is calculated as 120 g (NO_2)/kWh with the combination of NTP and the NO_x recirculation.

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Continuous operation tests of the boiler emission treatment plant which consists of a commercial ozonizer for indirect NO oxidation and a Na_2SO_3 chemical scrubber are carried out for gas firing and heavy oil boilers. For gas firing boiler emission, the NO complete removal and the decrease in NO_x from 32 ppm to 3 ppm are achieved. This performance is maintained for 300 min by keeping -30 mV of oxidation-reduction potential (ORP) of circulating solution in the chemical scrubber. Concerning the treatment of heavy oil boiler emission, the decrease in NO_x from 90 ppm to less than 25 ppm is maintained for 250 min by keeping -30 mV of ORP. However, the unreacted NO of 15 ppm is detected at a scrubber outlet because the O_3 for NO oxidation is inadequate. By sufficient O_3 injection for NO oxidation, NO_x removal efficiency can be improved.

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Diesel engines have been used in a wide variety of commercial vehicles. However, several problems must be solved. One of the major concerns is that diesel exhaust gas has more particulate matters (PM) including soot, which are suspected to be linked to human carcinogen. Then, more strict diesel emissions standards are being set in many counties. Recently, in order to reduce PM in the after-treatment of exhaust gas, DEGPBS (diesel exhaust gas perfect burning system) has been developed by COTEC Company, Ltd. In this study, we conducted numerical simulation of soot combustion in DEGPBS by the Lattice Boltzmann method. The inner structure of the filter was obtained by a 3D X-ray CT technique. Results show that the combustion reaction is well simulated to discuss the burning rate of soot particles in exhaust gas.

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Water purification and sterilization by plasma in water have been reported, recently. However, the mechanisms of those applications have not clarified enough yet. In this study, relations between discharge parameters and the water characteristics such as H_2O_2 concentration, oxidation reduction potential (ORP) and pH were clarified. H_2O_2 concentration increased up to 5 mg/l at f = 5-6 kHz when a positive pulse was applied. The value of ORP is decreased down to -150mV although the pH value was not changed when the positive pulse was applied.

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In order to understand the structure of vertical turbulence, the relation between Richardson number and the turbulence was investigated from observation data near the coast. The perturbation of vertical velocity normalized by the horizontal velocity was expressed by a function of Richardson number. A new formulation for eddy diffusivity was proposed from this relation. Using this formulation and Mellor & Yamada model, the vertical profiles for horizontal wind speed and for temperature were calculated and were compared with observed data. These results suggested that this formulation was reasonable.

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A low-environmental load surface modification technique for plating the fluorocarbon polymers films is developed using an atmospheric-pressure argon and acrylic acid vapor nonthermal plasma graft polymerization. The results of the T-type peeling test show that the peeling strength of copper plating on the treated PTFE (polytetrafluoroethylene) film is approximately 46 times greater than that on the untreated film. With scanning electron microscope analysis of the surface of the copper plating on the treated PTFE, it is confirmed that the hydrophilic surface of the treated film contributes to uniform copper plating.

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Electrostatic Precipitator (ESP) used discharge, therefore generated ozone. The high voltage electrode neighborhood is dissociation area of oxygen molecule contributing ozone generation. It depends on electrode geometry. In this study, the optimum electrode shape on ozone generation in ESP was experimentally investigated. The experimental ESP was two-stage-type which composed of a prechager, followed by the collecting section. The precharger consists of high voltage electrodes of saw type and grounded plate electrodes. The electric field distribution of the saw electrode neighborhood was changed by changing the saw tip angle, and the influence on the density of ozone was examined. The decrease of ozone generation was examined by the number of saw teeth.

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Experimental study has been carried out to verify the reduction of fuel consumption and CO_2 emission on hydrocarbon fuel combustion using the electro-magnetic resonance high efficiency combustion technique in the regime of far infrared ray. Experimental verification has been also conducted by using the co-axial diffusion flame, fuel spray combustion and practical boiler combustion. Especially, in this study, the method of the verification for energy saving of fuel consumption including the variance, standard deviation and heat release rate is examined in detail by means of practical boilers of once through boilers, smoke tube and flue boilers and steam tube boilers. The experimental results show that, the electro-magnetic resonance high efficiency combustion technique is very significant method to reduce the fuel consumption and CO_2 emission on hydrocarbon fuel combustion.

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Experiments of co-axial diffusion flame have been carried out to develop the high efficiency combustion technique by utilizing the electro-magnetic radiant materials. Methane produced by thermal decomposition of hydrocarbon fuels combustion can absorb electro-magnetic rays at the wave number of around 1200 cm^<-1>, which belong to the wave regime of far infrared rays. The main acquisitions obtained for the study are as follows: (1) the temperature rising rates of water container by co-axial diffusion flame in electro-magnetic field are always larger than those of non electro-magnetic fields at the range of 1.1 to 1.7 of air ratio, (2) such a phenomenon makes it possible to establish the combustion of lower air ratio on co-axial diffusion flame and the low air ratio combustion technique may be applied to achieve the high energy saving and reduction of CO_2 emission on many kinds of combustors including boilers.

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Experiments have been conducted to develop the high efficiency combustion technique to realize the high energy saving and low emission of CO_2 by utilization of electro-magnetic wave around 1200 cm^<-1> in wave number, which belongs to far infrared ray. It is well known that the hydrocarbon fuels such as methane and its precursor are able to absorb much electro-magnetic radiant energy near the wave number of 1200 cm^<-1>. These rays may lead to more accelerate enhance the molecular movements between molecules of fuel and oxygen, and consequently the flame temperature increases due to the acceleration of combustion reaction. The main results obtained for the study are as follows: (1) the average flame temperature rise obtained from co-axial diffusion flame of methane are approximately 80 ℃, (2) the effect of such electro-magnetic wave on flame temperature rise of fuel spray combustion is very effective as well as that of co-axial diffusion flame, and (3) the energy saving rate corresponding to reduction of CO_2 emission even at the demonstration test of boilers can be attainable in the range of 3% to 5%.

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This study is aimed at estamating the shear stress caused by which rising bubbly flow on sumerged flat-sheet membrane surface using CFD method in MBRs. Shear stress on sumerged flat-sheet membrane surface caused by aeration was simulated using CFD code (ANSYS CFX 11.0) and was compared to measured shear stress by shear sensor and was found to measured time-averaged shear stress values were almost 1.8 times larger than calculated mean shear stress suggesting the calculation of shear stress should be modified therefore suggesting a new method of modifying the shear stress working on the "wall". After modification, both of the calculated mean shear stress and measured shear stress are in good agreement suggesting the effectiveness of CFD for evaluation of mean shear stress on sumerged flat-sheet membrane surface.

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This paper gives a brief account of the improvements made in regard to control of oxides of nitrogen in diesel engine exhaust by utilizing the radical production associated with high voltage electric discharges. The studies were conducted on an actual diesel exhaust and a qualitative analysis has been made. The effects of reactor design, type of voltage, and cascade connection of adsorbents/catalysts have been studied. The reaction pathways were discussed as and when necessary. Finally, a prototype solar powered high voltage supply has been built so as to assist the cleaning of exhausts in the vehicle. This is a novel technique being developed for the first time with the intention of commercializing the discharge plasma technique in the automobile sector without penalizing the auto fuel.

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Particulate matter (PM) removal in exhaust gas emitted from a stationary diesel engine generator (displacement volume is 200 mL) is performed using ozone injection diesel particulate filter (DPF) regeneration. It is demonstrated that the DPF regeneration by injecting O_3 is achieved successfully at 250℃. The amount of O_3 consumed per PM of 1.0 g is 17.66 g(O_3)/g(PM) and the energy efficiency of PM combustion is 5.24 g(PM)/kWh. The repetitive regeneration of DPF by O_3 injection for practical application is also achieved successfully. The regeneration time is only 12% of the total operation time. It is estimated that a heavy-weight vehicle with the ozone injection DPF regeneration system can meet the new regulation by using electric power of 0.19% of the engine output This system will be applied for the exhaust gas treatment of marine diesel engine and automobile diesel engine.

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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°C. The experimental results were compared with the calculation result based on the previous proposed method to predict the diffusion process in the frost layer. The value of tortuosity was fitted to match calculation to experiment and it was found that the tortuosity values were nearly to the Le Gall's proposed method, and the parameter in the Le Gall's equation was fitted in the chilled condition and frozen condition.

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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 compared with the calculation result based on the previous proposed method to predict the initial crystal growth period. The growth of ice column was calculated and the thickness and density were fitted to match calculation to experiment.

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A room temperature magnetic refrigerator deserves our attention as a refrigerator without having to use environmentally hazardous fluids. The refrigerator had produced a maximum COP of 2.6 when the temperature at the hot end of the AMR duct was 24 ℃ and the temperature span was 5 ℃. In order to increase the temperature span, the AMR duct has been modified to a cascade structure. The performance of the refrigerator using the hybrid magnetic materials is reported in this paper.

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This paper deals with the cooling characteristics of a room-temperature magnetic refrigerator using an active magnetic regenerator (AMR): The AMR-based refrigeration cycle, which consists of a thermal storage process and a regeneration process, realizes a practical magnetic refrigerator running at temperatures close to room temperature. The AMR cycle has four sequential processes: adiabatic magnetization, fluid flow, adiabatic demagnetization, and fluid flow. We devise an appropriate simulation model of the cyclic heat transfer process inside the AMR particle bed. Then, the temperature profile inside the AMR bed and the cooling characteristics of the room-temperature magnetic regenerator are studied analytically. In addition, the validity of the analytical model is verified by comparing the experimental results with the analytical results. The results show that the larger the transferred fluid volume, the larger is the temperature difference between the hot and the cold ends.

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Sprit type air conditioners are on the increase for large building because of easy installed. Increase in sprit type air conditioners had air cooled heat exchangers, for example multi-type packaged unit system, causes increase in amount of sensible exhaust heat generated when they are at work. The likely explanation that this is one of causes of heat island phenomena is being discussed. In this study, the method of prediction for multi-type packaged unit system performances was devised, and COP and amount of exhaust heat from multi-type packaged unit system during operation were predicted. As a result, the higher outdoor temperature, the lower COP became. COP difference between our prediction and a test operated Daikin Industries, Ltd., falls within 0.5% under the influences of outdoor temperature. On the other hand, exhaust heat from sprit type air conditioners during one day which was predicted in sever hot day was occurred about 11 % larger than in standard summer day.

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The purpose of this study is to analyze the effect of cooling by the water atomization in semi-outdoor station. By the exhaust heat of train, the temperature of station is higher than that of the air. We established the water atomization in a part of the station. We measured the thermal environment and investigated about thermal comfort. The temperature descent by latent heat of water mist was 1℃〜2℃. Thexmal comfort indices were improved by the water atomization.

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There is increasing concern about the health effects of the severe thermal environment in urban area. Because of these situations, it is important to estimate the thermal comfort for environmental improvements and designs. For estimating thermal comfort, surrounding environmental components, especially clothing material, are important, because clothing material has an impact on thermal exchange between exterior environment and human body. In this paper, the heat and the moisture transfer properties were examined in various conditions. The heat and the moisture transfer coefficients were calculated from measured values such as mass, temperature and humidity based on heat balance of sensible heat and latent heat. The heat and the moisture transfer coefficients can be obtained at the same time using our own making experimental apparatus. The heat and the moisture transfer coefficients indicate how effectiveness of the velocity of wind, the thickness of clothing material and the differences among fabric were clarified. The radiation properties such as reflectivity, transmissivity and adsorption of clothing were measured. These data are utilized for prediction of human thermal comfort.

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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 invent Best Available Allocation Supporting tool for vending machines, develop it, and apply it to Obuse city, Nagano prefecture. We had measured vending machines for a year and proved the effect of the tool.

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The on-line performance monitoring of a heat exchanging process using water and steam, which is one of the key components of distributed energy supply system, has been develop on the basis of a theoretical model. By using an input-output model of the process, this performance monitoring first estimates output process variables and heat exchange performance of the process in response to the variation in measured input process variables. These estimated values are then compared with the measured ones for the on-line performance monitoring. The effective of this method for the normal operation under steady-state and transient conditions and for a deterioration of the heat exchange performance due to air accumulation in the shell has been clarified. Thus, this paper investigates a diagnosability for deteriorations of the heat exchange performance occurred at the inside and outside the tube of the heat exchanger.

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Counter flow types of heat exchanger having through fin creating the edge effect heat transfer enhancement with heat conduction effect, or twist fins stirring turbulence heat transfer promotion are examined by experiments. Four different types of the heat exchanger (no inserted fin, inserted fin, twist fins and twist fins with partition plate) were discussed based on the obtained numerical and experimental results from the view point of (1)pressure loss, (2)heat exchanged quantities, (3) temperature efficiency, (4)number of heat transfer units (NTU) and (5)exergy. The inserted through fins/twist fins were cleared to play an important role in the upgrade (performance up) of the counter flow type of the heat exchanger.

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In this paper, aerodynamic characteristics of the cross flow type of wind turbine were studied experimentally by using sub-scale model, considering the effect of guide vanes and its arrangement. The aerodynamics characteristics of the turbine for wind flow direction were discussed by reference to the power and the torque coefficients correlation of tip speed ratio for various combinations of approaching optimized guide vanes number and optimal configuration.

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The purpose of this experimental research is to reveal the aspect-ratio effect on the flow around and inside a cross-flow impeller. In order to eliminate the complicated casing factors that influence their performances, the impeller rotates in open space without any casings. As a result, by using hot-wire-velocimetry (HWV) measurements and by conventional flow visualizations, the authors divide the flow around the impeller into three areas, and observe the eccentric-vortex revolution inside the impeller. Using a particle-image-velocimetry (PIV) technique, the authors quantitatively show velocity distributions, whose accuracy is checked in comparison with HWV results. In addition, the authors define outflow rate Qo from the impeller, and show that the aspect ratio effect on the outflow-rate coefficient C_<Qo> is not negligible at aspect ratios less than one.

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Hydropower utilizes the "renewable energy" for electrical power production, providing 9% of electricity in Japan. Micro hydropower is in most cases "run-of-river", without dam or water storage. It is one of the most environmentally benign energy technologies and is useful for local independent power supply. However, the cost performance is the greatest obstacle to disseminate micro hydropower widely. In this study, for price-reduction of micro hydropower, a propeller of outboard motors was applied to a turbine blade. The blade was improved to achieve high efficiency and increased output. The lkW micro hydropower performance was examined by experimental study. As a result, the best performance was obtained as the output of 1.54kW and the efficiency of 31.8%.

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