Bio-coke which is the solid fuel using the biomass wide and distributed was developed. I worked on the cooperation type study which combined regional development with renewable energy. Blowfish was being cultivated as a part of town renewal by Tokamachi city in Niigata prefecture which an advanced place and a possibility of the Bio-coke was considered as fuel substitution of the heating boiler which is being used for a water temperature adjustment of the water tank. The town is a specialty area by Hegi soba, Bio-coke is made from the buck wheat chaff which is the industrial waste occurring there and if it’s possible to change to heat energy by a heating boiler, it can achieve local production for local consumption by the renewable energy in the area. Mechanical properties and it’s combustion properties of the Bio-coke grain-size of buck wheat chaff of a raw material could make the formation temperature were checked and estimated to achieve practical use of the Bio-coke for which buckwheat chaff was utilized here.

Agricultural biomass is a global issue. However, Agricultural biomass is difficult to utilize as base-energy due to be harvest season problem. Biocoke techniques can convert all of the biomass as a raw material. This study reports on mechanical properties for rice straw Biocoke in agricultural biomass. Especially, preprocessing condition classified to grain and fiber, mixed state by aspect ratio after crash. This experiment discussed on distribution of cool compressive strength by heating temperature conditions. This experiment obtained the following results. Compressive strength distribution exists peak value due to heating temperature condition. Before and after of peak value for compressive strength is suggested the possibility to influence of softening based on hemi-cellulose.

Ammonia has been attracting attention as a promising hydrogen carrier to solve the transportation and storage problems in a hydrogen society. In this study, plasma membrane reactor (PMR) to produce high purity hydrogen efficiently from ammonia by combining atmospheric pressure plasma and a hydrogen separation membrane has been developed. Compared to hydrogen conversion of 13 % with the typical plasma reactor, hydrogen conversion of 21.9 % with the PMR was obtained. Further, the purity of the hydrogen obtained by transmitting the hydrogen separation membrane is about 100 % and the hydrogen supply was stable at 20 mL / min.

Fundamentals of electrostatic precipitator (EP) and electro fluid dynamic flows are reviewed. First, a system of basic equations governing electrohydrodynamic ionized flows is presented. Based on the basic equations, the three-dimensional flow interaction for tuft or point corona for industrial EPs was investigated using both laminar and turbulent flow models. The secondary flow distribution based on laminar flow model forms a pair of organized donut-shaped rings generated from every corona or tuft points, while a pair of rings is less organized for turbulent flow model. Other analysis results for environmental improvements and plasma flows are briefly reviewed.

The particle behavior in ESP depends on the particle characteristic, electric field, space charge and flow pattern. Moreover, re-entrainment phenomenon is caused according to the condition. The new hole-type ESP was developed to overcome the re-entrainment in the ESP. The particle flow into the hole by ionic wind. The electric field of a collecting zone in the hole is zero. Therefore, it can be expected that suppression of the re-entrainment. It is important to understand the particle behavior in ESP. Particle image velocimetry (PIV) was used to grasp the particle behaviour in ESP. In the experimental results, the particle flow velocity increase with increasing primary flow velocity. The particle flowed in the hole, this is attributed to ionic wind and Coulomb's force. The velocity of tracer particles are fast in ascending order of Cu and Talc EG. Cu is the most suitable for the collection.

In order to incinerate heterogeneous fuel such as waste products completely, high excess air ratio was traditionally applied to the burning zone in the incinerator. However, from viewpoints of heat recovery efficiency and flue gas treatment, low excess air ratio at high temperature has been becoming more popular for the waste incinerator year by year. Meanwhile, technologies for NOx emission control should be stricter since high temperature and flame instability under low excess air incineration conditions intend to extend NOx formation. In this study, initial pyrolysis behaviors of wastes in their incineration processes were analyzed to investigate their contributions to NOx formations.

Selective non-catalytic reduction of NO_x by activated ammonia injection has been developed to broaden and lower the narrow temperature window for de-NO_x. A temperature window enlargement of 150 °C was achieved at the lower boundary of the window using activated ammonia injection. Hydrogen is activated ammonia species play an important role in the expansion of the reaction temperature range. The purpose of this research isto find the optimum conditions ofthe H₂ / NH₃ molar ratio for the development of low temperature SNCR method.The experiment was performed using a mixed gas of NH₃ / H₂ at a temperature range of 650-750 °C. Optimum H₂ / NO molar ratio was decreased with increasing reaction temperature. Optimum H₂ / NH₃ molar ratio was 0.3 in NH₃ / NO = 1.0, reaction temperature 750 °C. MaximumNOx removalwas about 80% in optimal conditions, NH₃ / NO = 1.0.

Ethylene gas was decomposed using a dielectric barrier discharge (DBD) plasma reactor. The ethylene gas was diluted with the gas mixture of nitrogen, oxygen and carbon dioxide as simulated gas in the transportation container. The DBD plasma was generated by a pulse switching power supply consisted of MOS-FET switching devices, capacitors and pulse transformers. The mixture gas was contained harmful by-products, ozone and carbon monoxide after DBD plasma treatment. An Ag nanoparticle-loaded zeolite was set in the catalytic reactor to remove the by-products. The catalytic reactions reduced the by-products produced by the plasma treatment. It was confirmed that carbon monoxide diluted with simulated dry air was oxidized to carbon dioxide by the catalyst and DBD plasma.

This article describes the bench scale experiments (the flow rate of odor gas about 1 Nm³ /min) for removal of the water insoluble odor (ethyl mercaptan (EM) and dimethyl sulfide (DMS)) using corona discharge. The odor concentration was adjusted by the bubbling of the odors solutions diluted the excess ethanol into cooling container. The concentration of the odor was successfully controlled by the flow rate of bubbling gas (N₂) and it enabled a stable experiment for a long period of time. The decomposition of EM and DMS was accomplished by the corona discharge reactor consisted of four stainless wires and achieved over 50% conversion at electric power of 15W. Furthermore, the experimental results suggested that the most of EM directly was due to decomposition into corona plasma not oxidation of the ozone produced by corona discharge. But the decrease of DMS concentration combined of discharge decomposition and ozone oxidation

In this study, the plasma actuator tube is proposed for nano powder transportation and for particle cleaning. Spiral electrodes are embedded both inside and outside of a dielectric transparent tube made of polystyrene. Applying AC voltage generates dielectric barrier discharge (DBD) inside the tube and produces a chemical reactive species such as ozone for decomposing pollutions. Nano powder can be transported by the induced flow originating from ion wind which is known as plasma actuator effect. Transported amount of nano particles with diameter of 30 nm was measured with variable electrode configuration and tube diameter. Ozone concentration generated in the plasma actuator tube was measured.

Plasma sterilization has a potential as an alternative method against conventional sterilization methods because it enables to operate at low temperature, low cost and high safety. In this study, we developed a small sterilization device to which plasma actuator is applied, and formed an air flow by generating plasma which can transport chemical species efficiently. Sterilization tests for two cases of air and water were performed. It took 2 min in the case of air and 15 min in the case of water. Reactive chemical species such as NOx are considered as the sterilization factors. The air flow generated by plasma was also enabled to enhance the effect on sterilization.

A novel rotational internal combustion engine is invented and investigated. In this engine, no reciprocating component is used, resulting in vibration-free operation. This engine mainly consists of a rotor casing, a rotor and a crank shaft. The rotor shapes as single-lobe peritrochoid curve. The rotor rotates by the crank shaft of eccentricity e and rotates itself in counter-direction by phasing gears. The rotor casing shape is defined as envelope curve of the rotating single-lobe peritrochoid rotor. The room between the rotor and casing performs the working processes for working gas; intake, compression, ignition, expansion and exhaust processes. The intake of premixed gas of air and fuel and exhaust of burnt gas are controlled by rotary valve installed on the combustion recess of the rotor-casing. The combustion recess is equipped with spark-electrodes for ignition. One of advantages of this engine compared with Wankel rotary engine, is easy and reliable sealing of working gas. In this engine configuration, that is, a sealing component is only installed on waist section of rotor-casing, instead of complex sealing system on a rotor in case of Wankel engines, resulting in high efficiency by low-leakage of working gas. In this paper, first, configuration and geometries of this engine with single working room are described. Next the prototype engine is introduced and the cyclic behavior of the working process of this prototype engine is explained.

Micro diffusion flame array burner is applied to gas cooking stove, in order to obtain high thermal efficiency for a finned heating bottom surface of a pot. The burner consists of co-axial double pipe micro burners. Fuel flow of propane, issued through the inner pipe, is encircled by outer air flow. Two types of burner, stainless steel outer pipe type(SUS) and copper outer pipe type(Cu), are employed to verify the effect of themal recirculation on a themal efficiency. Several types of flame are observed by combination of fule flow rate, air flow rate and the distance between buner tip and heating bottom plate; blue stable flame, luminous stable flame, open tip flame, lifting flame, and so on. Excelent themal efficiency is given in case of stainless-steel outer pipe burner, because of low heat loss by low themal conductivity of stainless-steel outer pipe and heat recovery by aluminum fins.

The effect of calcium into coal fly ash on trace elements leaching concentration has been investigated through the addition of suppressing material. This study aims to provide the useful reference in controlling As leaching concentration into the environment. Suppressing material, as the by-product of other industries which contain high calcium, has been proven in decreasing of arsenic (As) leaching concentration from coal fly ash. There are three suppression materials that have been tested, that is: calcium hydroxide (Ca(OH)₂), paper sludge ash (PS3) and filter cake (FC). Ca(OH)₂ and PS3 show almost 85-90% decreasing in As leaching concentration based on ICP analysis. Moreover, the XPS analysis results show that calcium oxide (CaO) is consisting in PS3 and calcium carbonate is consisting in fly ash sample H.

O/W emulsion separation with a spiral cross flow was conducted in various operation conditions with various filers. Depends on the flow rate and filter, the filtration rate varied significantly and the pressure loss of the filter also effect on the filtration rate and the separation ratio. Filtration rate increased with increasing the flow rate and the pressure drop, however the separation ratio was decreased significantly. When the filter was changed clay to alumina, separation efficiency increased significantly due to the surface interaction between the oil and filter.

Since Osaka plain faces the Osaka bay, land and sea breezes tend to develop there. To reveal the relationship between the land and sea breezes and air temperature in summer night, we classified the wind systems in Osaka area by using a cluster analysis and examined the relationship between each wind pattern and air temperature distribution. The result shows that sea breezes at night make air temperature higher in Osaka area. When a land breeze develops, the occurrence of a land breeze is relevant to a decrease of air temperature.

Numerical simulations were performed in order to evaluate the impact of the direct effect of aerosol particles on meteorology and air quality over East Asia. The online coupled Weather Research and Forecasting-Community Multiscale Air Quality (WRF-CMAQ) modeling system was applied from January to March 2014 for cases with/without feedback: two-way/one-way simulations. Ground-level shortwave radiation and PM_2.5 concentration in the two-way simulation were respectively smaller and higher than those in the one-way simulation over the Asian Continent, particularly in China with remarkably high PM_2.5 concentration. These differences indicate that the aerosol direct effect substantially influence the atmospheric stability, and therefore the dispersion efficiency of air pollutants.

Adsorption desiccant rotor driven by humidity swing operation simultaneously produces dry and warm air. This study aims to apply the desiccant dehumidification and heating to agricultural fields. This paper reports influences of desiccant properties on the adsorption outlet air condition at some different operating conditions. It was found that there were optimum values of the wheel rotation speed at which the temperature rise became the largest. However, regeneration air temperature strongly affected on the adsorption outlet air temperature since the cooled rotor during regeneration step absorbed heat of adsorption which is generated at the beginning of the adsorption zone. Excluding of this low temperature air is one solution to obtain higher temperature of process outlet air when the regeneration air temperature is low.

In a liquid desiccant system, sufficient mass transfer is necessary in order to achieve proper dehumidification of water vapor in the air. One factor that can greatly affect air dehumidification is the structure of a gas-liquid contactor. This study investigates the effect of different structure of gas-liquid contactor on the dehumidification performance of a liquid desiccant system. In this system, lithium chloride solution was used as desiccant. By holding the air volume flow rate, the solution mass flow rate, and the volume of the gas-liquid contactor as constants, the dehumidification effect of different gas-liquid structures were clarified. It is found that gas-liquid contactor with length to height ratios greater than one can provide better dehumidification performance. The results from this study can be used for proper selection of gas-liquid contactor structure in liquid desiccant and hybrid liquid desiccant air conditioning system applications under cross flow configuration.

Adsorption heat pump system is a growing and promising technology for providing thermal comfort compared with other conventional heat pump systems in the view point of energy and environmental conservation. One of the major drawbacks is, however, low heat and mass transfer characteristics inside the adsorber bed which leads this system towards low coefficient of performance as well as low specific cooling power and hinder this system from mass scale production. Part of the recent researches suggested that different heat exchanger shape would increase the heat exchange performance of the adsorber bed. In this study, a critical review has been performed to find out the suitable heat exchanger shape for adsorber bed in terms of specific cooling power.

An activated carbonmethanol pair is one of the most promising working-pair of adsorption cooling systems. Densified activated carbons had been prepared as new adsorbents by mechanical compression through the addition of small amount of polytetrafluoroethylene (PTFE) powders. The present study dealt with the preparation of high-density activated carbon fiber (HDACF), and experimental and theoretical investigations of the adsorption behaviors of methanol vapor on the HDACFs. Under the experimental conditions employed in this study, the molded ACF with a larger apparent density adsorbed more rapidly methanol vapor. This adsorption behavior is attributed to a faster removal of heat of adsorption from the HDACF. The numerical analysis results showed a rough agreement with the experimental results on transient behaviors of adsorption uptake and temperature of HDACF.

Storage-type water heating systems have been used widely in residential applications, and it is important to make the sizes of storage tanks smaller for space saving. One of the ways to realize that is to incorporate phase change materials (PCMs) into the tanks and increase the density of stored heat by utilizing the latent heat of PCMs. A simulation model has been proposed to analyze the performance of a water heating system with a storage tank using PCM. In this paper, the validity of the simulation model in which supercooling of PCM in taken into account is investigated by comparing experimental and simulated results concerning temperature distributions and changes of the storage tank and PCM during, storage, and discharging. The investigation shows that the simulated results coincide with experimental ones qualitatively.

For the storage of the renewable energy using formic aid, the combination of the direct formic acid fuel cell which can directly produce the electric power using formic acid and the CO₂ electrochemical reduction (ERC) which can produce the formic acid using the electric power derived from the renewable energy and CO₂ emitted from direct formic acid fuel cell has been proposed. In order to achieve this process, improvement of the formic acid production rate is required. It has been known that formic acid could be obtained at high yield Sn catalyst at ERC, however, production rate was still low due to the high overpotential. In this study, the supported Sn catalyst has been produced for the enhancement of the production rate of the formic acid by ERC. It was found that supported Sn catalyst showed higher CO₂ reduction current comparing to that obtained by conventional Sn nano particles.

There are a lot of hot springs in Fukushima. The thermal energy of the hot spring is a valuable energy resource. In this paper effectiveness as the heat source for power generation systems is investigated. The temperature of 70 ℃ or more and enough flowrate are necessary as the heat source for power generation systems of 10kW class. However there are few regions where this condition is satisfied in Fukushima. Because the potential heat of the hot spring water in Fukushima is not low, it is proposed to use the hot spring water as the heat source of power generation systems by compensating for shortfall energy.

Low grade thermal energy, such as waste heat from industry and renewable energy is abundant source. Organic Rankine cycles (ORC) is a measure to recover electricity from low grade thermal energy. In this study, an ORC 50°C level heat source was investigated by thermodynamic cycle analysis that is driven by sources. A cycle performance under given temperature condition was computationally obtained by Engineering equation solver (EES). 69 working fluids were calculated in EES, and compared in terms of net thermal efficiency. It was fluid that refrigerant R407C achieved the highest net thermal efficiency because its zeotropic characteristic.

Most of the geothemal resources are liquid dominated. Since turbomachinery is not suitable to convert the energy directly from the wet steam, then displacement type machine also should be researched. In this paper, simulation analysis are performed to adopt two-phase helical screw expander in a small total flow power generation system. Influence of operating conditions on each loss factor are clarified. Further more, the classification method of losses are indicated. It gives a effective improvement guideline for the any operating conditions.

The objective of this study is to evaluate the power generation performance of the axial flow propeller turbine, and ascertained that effective as a micro-hydroelectric power propeller in conditions of low-drop (drop the number of 1-5m) and small flow (Flow rate 0.1 ㎥/s or less). Further, we propose a micro-hydropower generation systems that combines a water wheel, controller, and generator to contribute to the spread of energy's local production for local consumption. In this experiment environment, measured a maximum generation output of 145W using a hydropower generation systems that power generation cost of 800,000 yen/kW. We has future subject to further improve the power generation efficiency of this system improving shape of the propeller, guide vanes of the installation, and ensure the effective head, etc. because the axial flow propeller turbine efficiency was 60% as low.

Thermoelectric generation systems are known as one of the exhaust heat recovery systems. Thermoelectric modules have restriction of operating temperature due to durability. Therefore, it is important to optimize the design variables in the restriction. In this study, the mathematical model of the thermoelectric generation system has been developed. Optimization of the design variable has become possible in the assumed environment and the restriction. The consideration for the optimization has been conducted, and the concrete ideas to enhance the output have been shown using the mathematical model.

This paper describes about “Ultra Lightweight Vehicle (ULV) ” which is able to drive with smallest size of body and the least energy. Small size and environmental-friendly mobility is demanded from recent automobiles social conditions. Then we examined equipping the air engine as a part of the development of ULV. The result of performance test of the compressed air engine, the maximum output was 339 W, the high output area was around 800 rpm. According the above results, we developed ULV-Air (ULV-A) with the compressed air engine. The results of the running test, the maximum speed was 23.9km/h, and the distance was about 4km. Through the evaluation of the comprehensive energy utilization by exergy, we investigated for the performance improvement of air engine and ULV-A. ULV-A is expected to use at the theme park in Nagano prefecture as one of the demonstration test, with production of air by woody-biomass generation system.

Saturated liquid density and vapor pressure for HFO-1336mzz(E) were measured in the temperature range from 300 K to 400 K at intervals of 10 K by the extraction method. Saturated liquid density is obtained in the pressure range from 736 kg/m³ to 1291 kg/m³ . Vapor pressure is obtained in the pressure range from 206 kPa to 2584 kPa. In comparison with HFC-245fa, saturated liquid densities of HFO-1336mzz(E) are less about 0.96 times at 310 K and 0.77 times at 400 K than those of HFC-245fa. Vapor pressures of HFO-1336mzz(E) are higher about 1.2 times than those of HFC-245fa. Experimental uncertainties are estimated to be 0.028 K for temperature, 0.4 kPa for pressure and 0.9 kg/m³ for density. On a basis of the present data, correlations of vapor pressure and saturated liquid density were formulated. The maximum deviations from correlations were 4.6 kPa for vapor pressure and 1.4 kg/m³ for saturated liquid density, respectively. The standard deviations from correlations were 2.1 kPa for vapor pressure and 0.7 kg/m³ for saturated liquid density, respectively.

We measured isobaric heat-capacities of liquid HCFO-1224yd(Z) by using a flow-calorimeter. Our group constructed the flow-calorimeter in 1986 for measuring specific-heat-capacity at constant pressure of HFC liquid refrigerants. Isobaric-heat-capacity measurement was applied to liquid HCFO-1224yd(Z), that is expected to be an alternative working-fluid to R245fa. HCFO-1224yd(Z) has a smaller value than 1/100 Global Warming Potential of R245fa. The heat capacity of R245fa was also measured by our group in 2015. The measurements for HCFO-1224yd(Z) are obtained at eleven state-points under a pressure of 500 kPa in a temperature range from 278 K to 323 K. The expanded uncertainty (coverage factor of k = 2) for heat capacity values is predicted as being from 0.38 % to 0.85 %.

The Ionic Semiconductor ^[1] has been a polymeric semiconductor that contained with some rare earth metal oxides. This semiconductor was an equipment of environment conformity type, since the environmental loading such as power consumption was remarkably small, and it was man and beast harmless. Various solvents and/or atmosphere were given powerful reduction effect (antioxidative effect) by the convenient and safety method with the semiconductor. ^[2] In the solvent and/or atmosphere the new active species were generated with the action of this semiconductor. These active species were applied in following fields; (1) the battery active reinforcement agents toward various secondary batteries, ^[3] (2) the power storage system based on the regeneration secondary battery, ^[4] (3) the energy-saving type heat exchanging systems applied circulation efficiency improvement with viscosity lowering phenomenon of heat exchange medium, ^[5] (4) the additive for fuel oil and/or engine oil with fuel consumption reduction effect and exhaust gas clear effect, ^[6] (5) the cooking oil degradation prevention system toward deep fling manufacturing process, ^[7] (6) refrigeration and/or thawing system toward keep of freshness of the food and/or selective accelerated ripening, ^[8] and so on. These effective phenomena were manifested by the active species estimated with being analogue of solvated electron. ^[9] The authors report the outline of development and practical applications of environmental conformity type our products and/or our systems. ^[10]

From a viewpoint of global warming and heat island countermeasure, development of systems without high-temperature-heat release might be important. Facility development to aggressively utilize solar energy and waste heat under careful consideration on environmental load is important. In case that we make artifacts in place of nature, we should know the nature roles, and should artificially reproduce the necessary roles. Our group calls this kind of engineering procedure as Natural Engineering. Plant leaf doesn’t change solar energy into high-temperature heat, but keeps ambient temperature. It rather lowers ambient temperature because of transpiration. From this point, we are proceeding to develop high-efficiency heat-release system imitating plant transpiration. In this report, we made a new radiator with flat-tube and porous ceramics which has a possibility to discharge lower-temperature heat than the ambient temperature, and the heat-exchanger performance is compared with conventional one. As a result, we found a new flat-tube radiator with porous ceramics outperforms existing flat-tube radiator with corrugate fin.

Effect of scale on heat transfer characteristics of the plate heat exchanger for binary cycle power generation were investigated experimentally. It is cleared that the increment of scale is proportional to the square of time. The amount of scale are closely relating to the composition melting in the hot spring water and the velocity. When the amount of scale is the same, the overall heat transfer coefficient changes by a hot spring ingredient. The degradation of the heat transfer performance varies with the velocity and chemical composition of the hot spring, and the way of the degradation is gentle one having a small proportional constant a.

Ionic wind generation in the narrow gap was investigated. In this study, dielectric barrier discharge (DBD) was used to generate ionic wind. The electrodes for wind generation were composed of 0.9 mm or 0.12 mm thick dielectric plate made of Pyrex glass, and 0.1 mm thick aluminum tape as discharge and ground electrodes. 13.5 kHz and 6 kV_pp ac high voltage with 2.3 kV dc bias was applied to the discharge electrodes. Two of such the electrodes were faced each other with distances ranged from 0.5 to 1.8 mm and the wind velocities in the space were investigated. Wind velocity more than 1.0 m/s was obtained in case where the electrodes distance was 0.5 mm with the dielectric plate of 0.9 mm thick, while less velocities were found with the dielectric plate of 0.12 mm thickness.

The demand of electricity increases because of extensive use of air-conditioning system during the hot season in the tropical regions, which increase the peak of electricity consumption. Therefore, in this study, solar cooling system with single-double-effect absorption chiller that use solar energy as an energy input can be a way to solve energy problems and also environmental issues. The solar cooling system is applied to a building in Universitas Indonesia. The consumption of electricity, gas and solar energy are the main discussion.

The ejector cooling cycle can produce sustainable cooling from solar thermal energy and exhaust heat. In this paper, we first report a successful implementation of the ejector cooling cycle within an air compression cycle providing 70 °C waste heat. The refrigerant R134a used in this cycle provides good performance, however it has a high GWP (Global Warming Potential) and its high pressure induce high electricity consumption for the pump and supplementary costs as the main parts must be able to resist 2 MPa pressure at 70 °C. With the objective of developing an ejector cooling cycle with lower pressure and lower electricity consumption using a low GWP refrigerant, we propose a new design of an appropriate cycle working with R245fa : this refrigerant could be replaced by a new low GWP fluid, HCFO-1224yd(Z), reported as having very close properties to R245-fa by the manufacturer.

For the optimum design of two-phase flow nozzle of CO₂ two-phase flow ejector, it is important to investigate fluid mechanics of high-speed gas-liquid two-phase flow. The purpose of this study is to investigate CO₂ two-phase nozzle flow in view of both experimental and analytical aspects. In the experiment, CO₂ in supercritical pressure condition was blown down into atmosphere through a divergent-convergent nozzle, where the mainstream profile of temperature was measured. Furthermore, velocity measurements of nozzle flow were conducted using by PIV system. Experimental data of both temperature and velocity show that the nozzle flow is considered to be supersonic flow. The experimental values of velocity are found to locate between the gas velocity and the liquid velocity of the 1-dimensional analysis by Kinoue et al.

Multi-split type air-conditioning systems for buildings, which have multiple indoor units, require energy-saving operation. However, their performances, including cooling and heating capacity and COP, are decreased during long operating times because of aging degradation of system components and refrigerant leakage from movable parts. Hence, a performance monitoring method to detect performance degradations and to identify degraded components online must be developed. As a preliminary survey, the present study analyzed the characteristics of a multi-split type air-conditioning system under the performance degradations of system components and the reduction in the refrigerant charge amount in the cycle by using our steady-state cycle simulation model. The decreases in the adiabatic efficiency of the compressor and the heat transfer coefficients outside the tube of the condenser and evaporator are examined as typical performance degradations. The numerical simulation revealed the distinctive trends of the system characteristics under the performance degradations and the importance of the performance monitoring under the normal condition to identify a degraded component.

Air conditioning system in data centers must cool year-round due to the large amount of heat emitted from the IT equipment. Therefore, it’s effective for air conditioning system to use low temperature outdoor air as direct/indirect air-side economizer. Air-side economizer can reduce energy consumption during cold season, but mechanical cooling such as refrigerant cycle must run during other season. Thus, we aim to develop high efficiency refrigerant cycle for saving energy consumption during hot season. So, we focus to the gas injection cycle. In this report, we verify to get guidelines for applying gas injection cycle to packaged air conditioner for data centers.

With the aim of energy saving and cost reduction for lumber drying system, we built a prototype a lumber drying system with a solar thermal collector, a water circulation type heat pump and a waste heat recovery heat exchanger. As a result of experimental study, this system can reduce primary energy consumption by 56% and energy cost by 60% compared to exsinting a steam drying system with a heavy oil-fired boiler, keeping the kiln-dried lumber quality high. In addition, we obtained some design guides for commercialization of this system.

A cogeneration system (CGS) powered by an internal combustion engine is generally enclosed with panels to improve thermal efficiency and reduce noise. On the other hand, there are upper temperature limits to maintain reliability of components in the CGS. Therefore, temperature prediction is important to design of the CGS. In this study, a thermal resistance model of the CGS has been considered for simplification of the prediction. Heating value of the heat sources has been defined by calculating heat flow through the thermal resistances which have been easily estimated by measurement of heat flux. The thermal resistance model based on heat flux measurement has been verified experimentally.

The objective of this study is to evaluate the performance of SOFC (Solid oxide fuel cell) installed in office or hospital buildings. The higher efficiency of power generation is considered advantageous for electricity oriented users in commercial sector. Optimization model to minimize the system cost with co-generation was employed to analyze how SOFC could be competitive compared with conventional system for large, medium and small scale buildings. The results suggest that SOFC is not expected competitive for office buildings while it can be feasible for hospitals for any building scale. The results also imply that the cost of SOFC needs to be reduced down to 500k¥/kW. Although SOFC is highly efficient in terms of power generation, utilizing co-generated heat is essentially important even for SOFC systems.

This paper presents design and evaluations of hybrid heat source system by sola are geothermal which are one of renewable energy. This research has done as part of the research in the "Honjo Smart Energy Town Project", which has been promoted in Honjo city, Saitama prefecture. The target of the project to realize or propose the effective energy utilization system is including business model. This system is mainly driving by the Geothermal Heat Pump for air conditioning with back-up of adsorption refrigerator which is driven by solar hot water. Solar heating system is used for hot water supply also. By measuring the collection heating value of solar in the summer the maximum calorific value was 1710 MJ per day. The maximum cooling calorific value from geothermal heat pump in the summer was 6700MJ per day. The effect of adsorption refrigerator was confirmed from the operational data.

In this study, CFD simulations incorporating Variational Continuous Assimilation (VCA) method were performed in order to understand indoor environment of a generic health services facility and to estimate demand of humidification. Before performing the simulations, an observation of temperature, humidity and velocity was performed at the facility. The observed data indicate that the relative humidity was low although some humidifiers were working. In order to determine the cause and countermeasure of this, the CFD simulations were performed. According to the result of CFD simulations, the low relative humidity is caused by large amount of ventilation, inappropriate location of humidifiers and shortage of humidification. Based on this result, the demand of humidification was estimated by the CFD simulations incorporating the VCA method.

The objective of this study is to evaluate the performance of the solar chimney installed in the warehouse by variation of directions. The airflow rate inside the solar chimney increases by stack effect. The solar chimney is installed in 30 degree intervals from the East to the West. A year thermal energy collection of the solar chimney tilted 30 degrees from the South is larger than the absorber facing the South. Also, number of air changes tiled 30 degrees from the South is larger than the South in the morning. However, it is smaller than the South in the afternoon. By setting two solar chimneys in the East and West, this system can ventilate throughout a day.

Aiming at reduction of the energy consumed in domestic use, research of an energy system corresponding to ZEH (Zero Energy House) is advanced. The authors are developing a hybrid heat source Stirling engine CHP (combined heat and power) system, which uses solar and woody biomass for a heat source. This paper describes improvement of characteristics on a solar tracking type collector made by a Fresnel lens, which have individual surfaces machined in the focus side or the receiving sunlight side, besides different shape of surface receiving sunlight. The test results are beneficial to design of the solar collector and presented a practical solar collector.

Bird strikes at rotating wind turbines have become serious issue due to worldwide exponential spread of wind power. To save wild bird life, especially for rare species registered in red list such as white-tailed eagle, a real time based system to avoid collision in wind farm is strongly desired. We have developed an automatic optical bird sensor applicable to natural background with help of a high-speed image processor coupled with a long-ranged high-resolution camera. In this report, we present how the image processing works for flying bird detection, and also how the bird species are identified to alert turbine-striking probability that is estimated dependent on bird species.

The vertical axis wind turbine isn’t sensitive to wind direction. However, since fast acceleration of the strong wind, it is necessary to prevent damage due to rapid increase in the rotational speed. In a series of studies, the aerodynamic brake to suppress the rise of the rotational speed has been taken up. When the rotational speed of the wind turbine is increased, the horizontal axis by the centrifugal force extends outwardly, at the same time, the brake plate attached to the axis is rotated 90°and the brake plate is subjected to a large air resistance. So far, the use of a suitable brake plates and springs suitable for a particular wind turbine can be widened operable wind speeds of the wind turbine. In this study, as a process to clarify the design guidelines to adapt the aerodynamic brake for a variety of vertical axis wind turbine, experiments using different sizes of the brake plates and spring constants are conducted and the effects of the elements are discussed.

For performance improvement of cross-flow wind turbine for small size wind power generation, a casing (Dual Flow Deflector Casing) with two flow deflector plates and tail plate was devised. The two flow deflector plates are to improve ambient wind environment of the wind turbine and the tail plate is for attitude control of the casing to face toward the wind. In this preliminary study, to investigate the effect of size of wind turbine, by using two types of small size wind turbine test models with different diameters (114 mm and 171mm respectively), The performance tests of these wind turbines with/without the casing were done. As a result, each size of wind turbine with the casing showed higher performance than that without the casing.