The effect of CO, NO_2 and NO addition to methane-air mixture as well as the initial methane concentration upon methane oxidation at T=600℃-900℃ and P=1atm was studied experimentally using a flow reactor. Faster methane oxidation was observed for higher initial methane concentration. The addition of CO(0-1000ppm), NO_2(0-500ppm) and NO(0-500ppm) also enhanced methane oxidation. Higher level of CO and NO_2 addition resulted in higher methane oxidation ; however, existence of an optimum amount of NO addition to promote methane oxidation was observed. The optimum value was found to be dependent on the residence time. The experimental results were compared with three reaction mechanisms proposed by Amano and Dryer [9], Bendtsen et al. [5] and Bromly et al. [6].

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In view of diminishing resources of fossil fuel, it is very important to device future combustion systems, which are capable not only for utilizing low quality fuels but also realizing ultra-low pollutant emission. According to the concept by Weinberg, a variety of heat recirculation type lean-burn burners have been proposed. Since they have complicated construction and exhibit extreme large pressure loss, however, wide application to industrial and commercial combustion systems have not been positively realized. In this paper an insert-type compact regenerative burner, which is not necessary for any additional equipments, is devised and its lean-burn characteristics are experimentally investigated. It is found that ultra-lean propane-air mixture of an equivalence ratio of φ = 0.19, being extremely leaner than the lean flammability limit of φ = 0.51 under STP, is successfully burned.

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In order to elucidate the enhancement mechanisms of turbulent flame propagation, it is indispensable to examine and clarify the detailed process of vortex-flame interaction.In this investigation a series of large scale organized eddies formed in the plane propane-air premixed shear flow are selected as an objective eddy field. Two devised techniques are introduced and combined with each other ; one is the acoustic excitation of the shear flow, the other is the simultaneous two-directional high-speed schlieren photography. The former makes the organized eddy formation extremely regular and enables synchronized ignition with a high-speed video camera. The latter gives the chance to analyze two different directional views of a same propagating flame. In this paper it is shown that the propagation velocity along the axis of the eddy is promoted by the vortex bursting and is greater than that in the radial direction by about 80 %.

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Fluidized bed system of photocatalyst is investigated for the preservation of atmospheric environment. A circulating fluidized bed (CFB) is adopted to develop the treatment system of large amount of exhaust gas. The composite particles of titania-silica are prepared by sol-gel method. The photocactalytic oxidation of nitrogen oxides (NOx) is studied. It is found that the gas-solid contacting in the riser part of CFB is important for the NOx treatment. The amount of TiO_2 content of the composite particles affects the cumulative amount of NOx treatment. The regeneration of photocatalytic activity can be achieved by heating. These findings can provide a basis for a proper reactor design toward successive treatment of large amount of gas such as tunnel exhaust gas using fluidized bed system.

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This paper describes the result of field measurements of nitrous oxide (N_2O) emission from fluidized bed sewage sludge incinerators. Continuous monitor of N_2O were done for 4 incinerators in 5-7 days for each incinerator. N_2O emission was changed with operation condition of incinerator and composition of sewage sludge. Generally, highest value was two times larger than lowest value. This results suggest that determination of N_2O emission factor by grab sampling may have low certainty. Determination of N_2O emission factor by a long term continuous monitor is required to make a good estimation of N_2O budget. N_2O emission was almost determined by the free board temperature in the incinerator. Emission factor obtained laid between 1500 〜 4700 g-N_2O/t- dry sludge. This value was much larger than the value published on "Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories" by IPCC.

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Recently, the air pollution caused by exhaust gas from automobiles is getting worse. Especially, it is very serious along arterial roads and at intersections with heavy traffic. Therefore, so far many researches have been carried out on nitrogen oxides removal systems. This time we have researched on absorptive property of nitrogen oxides and the power efficiency of this system. As a result, we found 1) the absorption of nitrogen oxides relies on the condition that water and gas are combined. 2) by changing pressure of the pump, power efficiency of nitrogen oxides removal system is improved.

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Recently, the air pollution caused by exhaust gas from automobiles is getting worse. Especially, it is very serious along arterial roads and at intersections with heavy traffic. Therefore, so far many researches have been carried out on purifying facilities. This time we have researched on absorptive property of SPM, CO, CO_2 and C_3H_8 and the power efficiency of this system. As a result, we found 1) the removal efficiency of SPM falls as the gas flow ratio and concentration increase. 2) CO and C_3H_8 are scarcely removed regardless of experimental conditions. 3) by changing pressure of the pump, power efficiency of our system is improved. However, it turned out that this system is not good enough as a SPM removal system under the present condition of pollution.

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To mitigate the global warming caused mainly by increase in atmospheric CO_2 concentration, a performance and characteristics of the gas lift system for deep ocean sequestration of CO_2 is numerically discussed. First, it is theoretically shown that they depend on the average void fraction in the system. Second, the numerical method based on the Drift Flux Model is employed, and finally the performance and characteristics at the starting operation are discussed.

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Systems for water and material cycles were proposed for Sustainable Marine City (SuMaC) which is a fictitious reclaimed island (800-900 ha) on Osaka bay coastal zone with 39,000 residents. In the water cycle system, highly purified water is supplied at 14,100 m^3/day for drinking, cooking, and bath. While, recycled water originated from domestic wastewater and rainwater is used at 4,470 m^3/day for flushing toilet, laundry, and others. In the waste recycle system, waste food of 7.2 ton/day, branches and weeds of 3.0 ton/day, and waste sludge of 3.2 ton/day are digested to methane at 1,300 Nm^3/day. Combustible wastes are incinerated at 17 ton/day for waste power generation with methane. Other domestic wastes of 19 ton/day containing papers of 12 ton/day are processed for reuse and/or recycle.

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Natural energy utilization was discussed for Sustainable Marine City (SuMaC) which is a fictitious island (800-900 ha) on Osaka bay coastal zone. In SuMaC, electricity demand is presumed 59.8 × 10^6 kWh/year. Potentials of natural energy such as photovoltaic power, wind power, tidal power, and wave activated power and recycle energy such as biogas power and refuse-burning power were evaluated considering weather conditions and the land use plan of SuMaC. The results suggest that electricity are supplied at 150% for the demands. However, in nature of natural energy, it was also suggested that the energy supply showed considerable time-lag against the demand. To solve the problem, establishment of total and zonal energy control centers was proposed for efficient energy storage and conversion in SuMaC.

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"World Econo Move" is the event competing for the driving distance with the battery under an equal condition. We designed and manufactured new Econo Move car with the aim of the low air resistance. And we tested performance of this new model car. From the test results coefficient and coefficient of rolling resistance were calculated. And those are 0.07 and 0.0018 respectively. We simulated drive range with these coefficient and running pattern. This simulation revealed that new model's drive range is 73.39 km.

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As a source of environmental load, some stages exist such as industry, transportation, and a public-welfare section. And in our everyday life, there are many consumptive actions that affect environment. So in case we estimate various environmental problems, we must consider the effect of our daily life on the environment. The environmental load that an individual brings is very small compared with what an industrial section brings. And it was not clear that actually how effective it is with an improvement in behavior. So positive measures, such as an improvement of a life style, were taken only by the part. However, we must choose our acts and wrestle environmental problems for ourselves in the future. In this report, we put ELP (Environmental Load Point) to the LSA (Life Style Assessment), and estimate the reduction effect of environmental load by improving our actions on Life Style.

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This paper describes a LCA (Life Cycle Assessment) and LCC (Life Cycle Costing) evaluation for three types of power generation systems that are natural renewable, fossil fuel, and nuclear power plant systems, with the validity of optional equipment for environment. In this work, the power plants inventory database has developed to support a deterministic quantitative model to compare the technical-economical and environmental features of various electric power plants. The each optional equipment leads to changes in flow of energy, materials consumption and exhaust emissions. The LCA-NETS method that proposed here is used to analyze the environmental performance of each power generation system in the lifecycle, and the LCC is used to evaluate the economy parameter. Such consequence can be evaluated by input-output analysis, and direct and induced environmental loads are finally obtained.

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Life Cycle Assessment (LCA) has been greatly paid attention to its effectiveness in evaluating environmental impacts through the lifecycle of any industrial products. In this paper we are focusing the evaluation of metal processing such as cutting, bending, stamping etc. during manufacturing process. The ESS-LCA method is used to analyze the environmental load of the process. As a result, the inventory data system of the metal processing has developed and, a list of estimations using NETS values as points of reference for further development and refinement to much more environmental friendly manufacturing.

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Life Cycle Assessment (LCA) is important as environmental problems become more critical. So. LCA is a method for assessing the cradle-to-grave environmental impacts of products. The algorism "ESS (Eco-Load Standardization Scheme)" as LCA method is proposed and the LCA software "MieLCA" based on. ESS is constructed. The MieLCA made possible evaluation of various industrial products rapidly and easily. As an example of industrial products, reduction of environmental load of vending machines which using reused parts has been evaluated with MieLCA. The results demonstrate that vending machines with reused parts reduce environmental load.

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In recent years, consumption of resource causes some environmental problems and it is demanded to consider a countermeasure for these problems, especially disposal and recycling of waste. Therefore, to structure the circulating economy which contains the recycling and. reduction of waste is needed. In recycling system, it can reduce the load for environment to carry out the process in short circuit. From this point of view, we proposed an Eco-Production System (EPS) which organized from material recycle and parts reuse. This paper says about classification of products for EPS.

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In recent years, consumption of resource causes some environmental problems and it is demanded to consider a countermeasure for these problems, especially disposal and recycling of waste. Therefore,to structure the circulating economy which contains the recycling and reduction of waste is needed. In recycling system, it can reduce the load for environment to carry out the process in short circuit. From this point of view, we proposed an Eco-Production System (EPS) which organized from material recycle and parts reuse. This paper says about proposal for evaluation method using material intensity and estimate of recycling technologies

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In this paper the application of a passive system with gypsum board impregnated with PCM in summer was investigated by numerical simulations. The Macro model without calculating air flows was used to simulate the thermal performance of PCM wallboard for a month in Osaka, Japan. It was found that the PCM wallboard in optimal conditions can reduce maximum room air temperature and improve thermal comfort relatively compared with conventional gypsum board.

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Electric power used for air conditioning in the summer time has been increase year after year. To reduce summer peak demand, an ice-based heat storage system, which makes ice using surplus electricity during nighttime and utilizes the accumulated ice for air conditioning in the daytime, is developed. The ice heat storage system needs sophisticated technology that enables to accumulate heat effectively and utilizes the stored cold energy from ice efficiently. We have developed a technique that brings about substantial increase in heat transfer by supplying fine air bubbles between the piping of refrigeration and formed ice when melting the ice. Our repeating experiments on the heat transfer performance proved that substantial increase in heat conductivity was achieved. In this paper we show configuration of the system and how it operates.

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Ice thermal storage systems are being developed and marketed as one of the means of electric load leveling and Ice slurry systems are developed to offset some of the disadvantages of the conventional static systems. Agglomeration of slurry ice, however, is still a big problem. This problem has up to now made transportation of pure water slurry ice, which is environmentally friendly a challenge to industry. Various surfactants have been studied and bio -surfactants, which are inexpensive and environmental friendly have shown good characteristics as agglomeration inhibitors. This paper reports on both laboratory and bench plant evaluations of some of the surfactants tested as agglomeration inhibitors.

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There is a jump in the demand of LNG (liquefied natural gas) as alternative energy of oil. When LNG is vaporized, it releases a great number of cold energy. From the energy saving viewpoint, the utilization of LNG cold energy is very important for the refrigeration industry concerning low temperature region. As the purpose of the utilization of LNG cold energy, the heat storage system with phase change due to direct contact has been considered. In this system, the cold energy of LNG transfers directly to the bulk with freezing. Accordingly, two phase changes of evaporation of LNG and freezing of the bulk is occurred at the same time. The liquid-liquid direct contact heat transfer with evaporation has been investigated theoretically and experimentally, using a R134a drop injected into water. The calculated results agree with the experimental results for the contact evaporation state.

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This study examines pressure drop and heat transfer of a heat transportation system equipped with a fan-coil-unit using surfactant solution as heat medium. It was clarified that total pressure drop of the system using surfactant solution is less about 50% than that of the system using water only . Heat release rate of a fan-coil-unit using surfactant solution system is less about 10% than that of the water system.

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It is the item that waste heat recovery is important in addition to the generating electricity in co-generation system. Though hot water recovery and the heat recovery of the steam are generally known from waste gas, the absorption chiller heater which is driven by the waste gas of the micro-turbine is introduced in this report. The absorption chiller heater which is driven using waste gas at 280℃ and 820m^3 (N) /h from the micro-turbine could raise the waste heat recovery efficiency by the absorption action of the single effect and the double effect cycle, and could also achieve at 14USRT of air-conditioning ability.

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With their background of energy-saving and environmental attributes, gas engine-driven heat pumps (GHP) are growing in popularity. They have created a firm position in the medium-to-small-scale commercial space cooling and heating market in particular, but products developed for residential applications have recently been attracting attention. On the other hand, even greater efficiency is being demanded in order to cope with global environmental problems and energy issues. As for GHPs, in addition to more highly efficient devices such as engines and compressors, waste heat recovery is an effective method to improve efficiency. This paper introduces systems for utilizing the waste heat from residential GHP to provide comfortable air conditioning and efficient supplies of hot water.

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Aerodynamic performance characteristics of the HAWT were investigated theoretically and experimentally by the combination analysis of momentum, energy, and blade element theory superimposed by the strip element theory, and by a small-scale model, considering the angular rotation of working flow, hi this study, four types of wing section and arrangement of blade were examined by a small scale experiments under the condition of open typed wind tunnels with free stream 0.8〜4.5 m/s and outlet ducts dia. of 0.88m φ. i.e., tapered rectangular blade with NACA44, LS04 and two-stage pitch angle tapered blade and tip oval tapered blade with NACA44. The aeronautical characteristics of the H. A. W. T. employing the different blades were discussed to the relation of C_P, C_T, C_q and tip speed ratio λ, based on the experimental and analytical results. Prediction results of aeronautical characteristics for large scale unit are cleared how to be optimized design parameters acting as significant role.

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Vertical axial cross flow type of wind turbines by means of the momentum exchange of fluid flow are considered to have superior characters in comparison with the conventional propeller type of HAWT, especially in combined with outer static guide vanes. Expected merits are to operate for all directions of the wind without the mechanism of yaw drive systems, and to have a considerable strong starting torque, which lead to simple structures and low costs. From a view point of above aspect, aerodynamic performance characteristics of the cross flow type of wind turbine combined with outer static guide vanes were studied experimentally by small scale model under the condition of open-type wind tunnel with max. wind stream velocity 4.5m/s and outlet duct's dia. 0.88mφ. The free stream velocity was regulated from 0.8 to 4.5 m/s by a 1200 mm dia. two blades, propeller driven by a 400 W controlled induction motor. The mechanism of the cross flow model in this experiment are involved the rotor with 0.32mφ dia. and 0.3m wide comprised of flat plate blades and advanced blades modified to attaching the 10mm curved front corner, as a parameter of pitch angle θ_g, θ_r and blade/vane numbers Z_g, Z_r. The aerodynamics characteristics of the turbine obtained by experiment were discussed and correlated by the tip speed ratio and power and torque coefficients C_P, C_q for various parameter combinations.

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This paper analyzed a small-scale distributed cogeneration system, where the heat is supplied from the individual fuel cell equipped at each house and the electric power is provided by an electric network constructed on the houses. Each fuel cell is permitted to stop a day. Combination of once on-off patterns produce a similar pattern with the actual electric demand pattern. Energy utilization analysis has been made on this system using the energy consumption pattern measured for 37/26/11 residential houses. Evaluation of heat demand shows that the heat demand becomes larger than the heat provided from the system at the power-generation efficiency above 0.26. Total efficiency of the system exceeds that of the conventional system with the large-scale network and gas fired heat supply at the power-generation efficiency above 0.24.

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In recent years, energy conservation is one of large social problems and many studies with respect to combined heat and power have investigated the potential of energy saving. It is required to predict energy demand in the future in order to estimate how CHP can reduce primary energy consumption. The objectives of this study are analyzing the trend of daily load curves for electric power, cooling and heating in residential and commercial sectors ; and forecasting future load curves in the years of 2010 and 2020. Energy demand in each time period is correlated to GDP and seasonal temperature, and regression analysis gave good estimation with correlation coefficient of almost unity for most of periods. The results show that peak demands for cooling and heating in 2020 grow 1.9 times and 1.6 times as much as that in 1997, respectively, under the assumption of GDP growth rate of 2%.

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A simplified formula for calculating effective transmission-absorption factor for the tube of evacuated tubular collectors is presented in the present paper. It is culculated from the index of refraction and the attenuation factor of the glass, the abrorptance of the absorber, and coefficients for the absorber character. The results by this formula are compared with results by ray-tracing due to validate the accuracy. By using this formula, effective transmission-absorption factors under various solar spectrums are calculated. The result shows the performance of evacuated tubular collector under direct solar spectrum is so different from that under diffuse solar spectrum that the difference between the performance under direct and diffuse solar radiation should be considered when the performance under natural solar spectrum is calculated. And brief coefficients sets for this formula for various feature's evacuated tubes are presented.

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The characteristics of the Effective Transission-Absorptance factor for evacuated tubular collectors with three types of back reflectors are presented. The problems how to reduce the computational time, how to simplify the program and how to calculate the incidence angle modifier are discussed. The results show that the performance of evacuated tubular collectors is subject to huge variation with the position of sun and the distribution of the diffuse radiation intensity on the sky. The performance of the evacuated collector with a diffuse reflector is higher than it with mirror reflector at noon. However The both performances are almost equal when they are evaluated as the all-day performance. The danger of evaluation by short time testing was indicated. Testing throughout several days, at least a day, may be recommended.

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The outlet air temperature of a solar collector would be required to be as high as 50℃ for heating rooms and hot water supply in the winter time and as low as 80℃ in the summer time for protecting the fan from the heat-resistant problem. In this study, the outlet air temperature of a collector was tried to be constant by adjusting the flow rate of the air by means of using an inverter to regulate the power for the fan. A non-steady state analysis on the thermal performance of flat plate collectors was also made for aiming to apply the analysis to simulation of the performance of collectors for various conditions. It was found that the outlet temperature of the collector was stable and was kept constant during the daytime and that the analysis would be useful for simulating the performance.

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To utilized solar energy, it is important to evaluate exactly insolation characteristics as yearly amounts, monthly and daily average value, include direct component in global insolation, etc.. For this purpose, the global and direct insolations measured by the author twenty two years at Kitami and measured meteorological agency from eight to twenty years in fourteen locations, such as Sapporo('78 to '97), Miyako, Matsumoto, Shionomisaki('81 to '97), Nemuro, Akita, Tateno('82 to '97), and other seven locations(Wajima etc. '90 to '97) were processed. Consequently, it was made clear that a monthly distribution pattern of the global and direct insolation for fifteen places. And hourly distributions of the direct insolation in fine days were shown. And for daily insolation of every day, it was shown average, maximum, minimum values. Furthermore, frequency distributions of daily insolation at Kitami and Sapporo were made clear.

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The fundamental heat balance was evaluated by numerical simulation for a solar heat system with long-term latent heat thermal energy storage using supercooled phenomena. The supercooled thermal energy storage (Super-TES) stores thermal energy at temperatures lower than the melting point of the phase-change material, which reduces heat loss from the storage system. The thermophysical properties of disodium hydrogenphosphate dodecahydrate were used for the calculation. From the results of the calculation, we found that Super-TES exceeds conventional latent heat thermal energy storage (LHTES) in both energy and exergy efficiencies to store surplus solar heat in the summer till the winter. The difference in efficiency between Super-TES and LHTES increases with increasing period of the storage in the supercooled condition Especially, Super-TES contributes for saving available energy (exergy) more than for saving energy.

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The linear compressor is a piston-type compressor in which the piston is driven directly by a linear motor. The free piston linear compressor has the potential to reduce friction losses and achieve better efficiency. It also promises life and cost benefits. The authors developed our original 2 piston-type linear compressor for refrigerators. This linear compressor operates at 60Hz, uses R134a as refrigerant, and has a cooling capability of 230kcal/h. The results of performance tests show EER of over 1.40. In this paper, we introduce the specifications and the performance test results of our 2 piston-type linear compressor.

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We have a conclusion that the hybrid heat pump system is usable for melting snow from viewpoints of the performance and the economical effect, which uses dual heat sources of the geothermal and the ambient air by means of two evaporators in series arrangement. The addition of a geothermal-source evaporator next to the air-source evaporator of a heat pump tends to increase the pressure loss of the refrigerant flow in the process of evaporation. The most difficult subject for the hybrid heat pump system is to lessen the pressure loss without dropping the performance of the heat transfer of the geothermal-source evaporator. In this development, the above subject was solved by means of using small-sized flooded-type instead of dry-type for the second evaporator, and the performance of the heat pump was improved sharply.

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This paper study on year-round cooling type packaged air conditioner by incorporating a refrigerant pump. When outdoor air temperature is low, the efficiency of year-round cooling type air conditioner can be improved by circulating refrigerant by the refrigerant pump. This paper discusses field trial results and calculates energy saving effects based on cooling capacity and electrical consumption at field trial. As a consequence result, this air conditioner can save more than 50% electrical energy at Sapporo and more than 40% at Tokyo in comparison with ordinary air conditioner.

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"Condensing Units" consists of a compressor and condenser and can be used in combination with various evaporator units such as display-case type refrigerators and cooling coils for cold storage. Many of these units are installed in food retail stores of supermarkets and convenience stores, which carries the problems that condensing units consume more than half of the entire electricity demand of the whole stores. Gas engine condensing units (GCU) are developed using GHP (Gas Engine driven Heat Pump) technologies, which have the same characteristics as GHPs. The compressor of the GCU is driven by a natural gas engine, thus requiring little electricity and therefore solving the electricity problem in the stores. The GCU can reduce not only energy costs but CO2, NOX and SO2 emissions compared with conventional systems because of the cleanliness of natural gas.

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We have been developing a heat carrying system using CO_2 as a secondary refrigerant. The main target of this system is large-size refrigerator for commercial use like show-case for supermarkets. This system is composed two cycles, one is refrigeration cycle using R22, R134a or HC, the other is heat carrying cycle using CO_2. Due to this cycles, the amount of primary refrigerant can be reduced drastically. In this paper, we described basic composition and the specifications of the CO_2 heat carrying system, test results and evaluation of its performance.

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It is expected that CO_2 heat pump water heater performs enough heating capacity and high efficiency even in cold area. For the performance evaluation of this system, a test unit was operated in winter, in the open air. The heating capacity reached 4.5[kW], that was our target for residential use, at -20[℃] of ambient temperature. Annual average COP calculated on the weather data in Sapporo showed that CO_2 heat pump water heater was better than other heating systems in TEWI evaluation.

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A cup vending machine needs both hot water for hot drinks and chilled water and ice for cold drinks simultaneously. In a conventional cup vender, an electric heater is used for water heating and refrigeration circuit is used for water cooling and making ice. Using CO_2 heat pump system, hot water can be obtained from high pressure side and chilled water from low pressure side simultaneously. So it will be expected that the energy consumption and global warming potential is reduced by using CO_2 as working fluid. This report is described the performance evaluation of a cup vending machine applying CO_2 heat pump system.

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Influences of a surfactant on performance of a novel plate type absorber have been investigated experimentally. Experiments were conducted on the vertical flat plate type absorber for absorption refrigerator/chiller, with changing surfactant's concentration. Surfactant(n-octanol) concentration was varied in the range of 0〜100ppm. Temperatures of LiBr aqueous solution, cooling water and heat transfer surface were measured minutely. Furthermore, flow conditions of LiBr aqueous solution were continuously observed optically by using a high-speed video camera. Refrigerating capacities were calculated from those measurement results. Results showed that absorber performances were significantly enhanced with increase of surfactant concentration. In case of surfactant concentration is 100ppm, absorber performance became about double than that case of no surfactant. Also, many protuberant "ropey" flows of LiBr aqueous solution were observed at upper region in the plate. These ropey flows swung side to side horizontally with a frequency of about 10 hertz. Consequently, it has been confirmed that those improvement were caused by the occurrence of Marangoni convection in the solution flow when the surfactant was added.

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Mixing of gas and solution in a bubble type absorption system is better than that in a falling film type. This study is investigated a bubble formation of NH_3 gas absorption. The gas is provided through a single orifice into ammonia aqueous solution under system pressures of 0.1 to 0.4 MPa. Concentration of the solution is from 0 to 0.1 kg/kg and temperature is at 295 K. System pressure has an effect on the shape and the spherical equivalent diameters (bubble diameter) of initial bubble. It is clarified that bubble diameter increases with increasing NH_3 vapor Reynolds number and decrease with increasing system pressure at low gas flow rate.

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In recent years, the absorption refrigerant cycle using H_2O -LiBr solvent as working fluid has widely been used in Japan, as a standpoint of energy shortage. However, This type of air conditioner and chiller is difficult to refrigerate because of the properties of the working fluid. Against this working fluid pair, there' s the absorption refrigerant cycle using NH_3-H_2O solvent as working fluid. This cycle is available to apply the system for various uses. But this type has not popularized for regulation in low in Japan so far. As a result, in this study TFE (2, 2-, 2-Trifluroethanol)/NMP (n-Methy-2-Pyrolidone) was picked out as a working fluid, and the evaporation heat transfer coefficients are measured to grasp a thermal characteristic of TFE/NMP mixtures in a capillary wick, that was applied for the proposed effective absorption cycle using a capillary wick in the generator.

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This paper describes a new energy-saving method suitable for absorption air-conditioning system. The energy savings are mainly obtained by applying variable flow rate control for cooling water. Cooling water flow rate is controlled to optimal condition for air-conditioning system with cooling water temperature, cooling load and absorption cycle as operating parameters. By adopting this method to gas-fired absorption air-conditioning system, energy consumption of cooling water pump is reduced by 30%, thus reducing the energy consumption of the air-conditioning system as a whole to 80%. This paper also describes the field test results of this system.

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An absorption refrigerator is getting attentions as a waste heat recovery system in a cogeneration system. To improve the efficiency of the cogeneration system more, it is indispensable to improve even the efficiency of the absorption refrigerator driven by waste heat. But to drive the absorption refrigerator with waste heat, it is difficult to advance the cycle and improve the efficiency. From this reason, if the cold heat is only obtained, the efficiency can not be enhanced greatly. Therefore this research suggests the absorption heat pump which can supply the cold and the hot heat which has been conventionally rejected as the cooling heat in the absorber and condenser, and analyzes the performance of this system by the simulation. As a result, In mode 3, COP_T is the highest in three modes, and its value is 2.52 for the working fluids H_2O-LiBr+LiI+LiCl+LiNO_3 when the cold heat temperature is 5℃ and the hot heat is 50℃.

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It is necessary to use waste heat from thermal engines effectively for promotion of effective use of energy. Although hot water supply, space heating and so on are raised as heat directions, the amount of use is restricted in summer. However, absorption cycle driven by waste heat is useful for that purpose. The purposes of this study are to improve a coefficient of performance (COP) for water / lithium bromide absorption system, and to evaluate the feasibility for use of various waste heat sources. And, the some of results obtained by this study are as follows. (1) Energy analysis in the absorber and generator in which heat transfer and other unit operation exist was performed, and some findings were obtained. (2) In the double-effect absorption cycle, COP and exergy efficiency was calculated and the cycle evaluation was performed. (3) Some of improved cycles for double-effect absorption system were examined to clarify the advantages.

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This article presents a numerical investigation of two-stage adsorption chiller with silica gel as adsorbent and water as refrigerant. Two-stage adsorption chiller can operate with waste heat (50〜70℃), so This is energy system which can use effectively unused energy. But performance of this chiller is worse than performance of conventional chiller, so need improve performance. In this study, a simulation investigation find the ratio of silica gel weight which is the upper stage and the lower stage for which this chiller attains good performance.

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The use of waste heat of low temperatures is an important problem from the environmental considerations. Notice that adsorption cycles have a distinct advantage over other systems of their ability to produce cooling by using low waste heat and also being absolutely benign for the environment. However the present available adsorption chillers are not suitable to adapt the systems like fuel cells with producing low waste heat less than 60℃. Hence we proposed a new adsorption refrigeration cycle combined with a mechanical booster pump which is placed in between adsorbent beds and condenser to reduce the pressure inside the adsorption bed for regeneration, or evaporator to be adsorbed at pressurized condition, that is, in order to increase an amount of driving refrigerant per cycle. This work deals with the performance testing of a cooling system based on a new adsorption cycle with a cooling capacity of 50 kW, an estimated cooling COP larger than 10.

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Adsorption refrigerator driven by waste heat at low temperature and regenerative energy is effective cooling machine at the point of energy saving and global environmental problem. The refrigeration system performance depends on the charactorlistics of adsorption reactor. Experiments were performed for heat and mass transfer in a packed bed of activated carbon fiber adsorbing water vapor or methyl alcohol vapor. The adsorption rate of methyl alcohol vapor, and the rate both methyl alcohol and water vapor decrease as the bed thickness increased. It was confirmed that this reduction attributed to a resistance to heat conduction within the bed. The influence of volumetric rate of bed on adsorption rate was examined. In a compressed carbon fiber bed ,that is a high volumetric rate bed, it was confirmed that the adsorption rate and amount of adsorbed water or methyl alcohol per volume of the bed increased. It suggests the reduction of a reactor size.

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