Interaction between Savonius turbine and Darrius turbine as they rotate coaxially in uniform inflow is investigated experimentally. When they are arranged closely with the tip-radius ratio of 2.5, Darrius-to-Savonius interaction is examined by measuring the change of rotational speed relative to isolated Savonius turbine in uniform flow. Its inverse, i.e. Savonius-to-Darrius interaction, is evaluated by lift force of the blade subjected to flow around Savonius turbine measured by PIV. The results have shown that the Savonius-to-Darrius interaction provides improvement of Darrius turbine performance at middle range of tip-speed ratio. Therefore, hybridization of these two turbines is concluded to be suitable not only in artistic designing for realizing compact design, but also in the aspect of fluid dynamics.

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In recent years, the importance of renewable energy has been increasing because of the need to prevent global warming. In order to decrease the impact on the environment, a lot of wind turbine generation systems have been actively introduced all over the world. The importance of the Yaw control system of large wind turbines rises in this situation. The investigation and analysis for the large wind power system with trail torque mechanism, THK-R Guide and Gearless structure, the application and possible result for the Trail Control Installation and R-Guide in the large wind power system.

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Wind power generation systems contributes to diversification of energy source and reduction of foreign dependence degree as a domestic energy source, and contribution and achievement of earth environmental safeguard, economic activation, a job creation effect, reduction of the environmental load and energy security are possible at the same time. In this study, trial manufacture of horizontal axis wind turbine and vertical axis wind turbine are introduced, and simulation is applied.

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In this study, prediction simulation of electric generation per year is done for small wind power generation system by wind condition. In result, calculation result of simulation become realistic value, and prediction of quantity of generation is made easy.

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Recently, new wind turbine generator optimized for the wind turbine output is proposed. This wind turbine generator is made of PM generator and is using neither control circuit nor PWM converter. In this time, straight wing non-articulated vertical axis wind turbine set up to company building and development of generator. The generator has merit that peak-torque is reduced. Afterward, the electrical power characteristic is acquired of field test.

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We have started the research of application for comprehensive wind energy since 1976. The research has continued for more than thirty years. The topics of the research include the design of best suitable turbines, wind characteristics, wind energy density and reserve, the efficiency of the wind power system, etc. Both the Straight Win Fixed Pitch Vertical Axis and the Horizontal Axis wind power systems have done the wind tunnel experiments and field tests. The research results also cover the relevant running tests, determination of the boundaries, stress tests in limits, etc. This report is the summarized statement for the most up-to-date experimental results of the Straight Wing Vertical Axis Wind Turbine power system.

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When the wind farm is built, it can't get the expected amount of power generation in many case with an influence of the wind turbine wake by the arrangement of the wind turbine. Then, the wind model which can calculate the wind which took the influence of wake into consideration in complex terrain was developed. Wake formation is modeled by the momentum theory, and included' into the k-ε model, and the decrement of the velocity of the wind is found. This paper describes how to write a manuscript of the 15th PES Proceedings.

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This paper describes the pole change type wind generator using fuzzy control. The pole change generators are the 16 poles. The conversion pattern of this generator is the 4 pattern. Specifically it is the 2poles of 8 parallel, 4 poles of 4 parallel, 8 poles of 2 parallel, and 16 poles. The experiment of the pole change generator used a small windmill and the electric double layer capacitor. The fuzzy control using multiple parameters is investigated in this paper. Experiment study on the effectiveness of the proposed method.

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In the present paper, the effectiveness of a vertical-axis wind turbine with a wind collector is confirmed. A wind turbine performance characteristic examined for the wind collect board angle and position. This characteristic is used to confirm the increase in the tip speed ratio and the power coefficient associated with the introduction of the wind collector to the vertical-axis wind turbine.

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Especially, the installation of the wind power generation with high cost-effectiveness is top priority to solve exhaustion of fossil fuels, CO_2-reduction while the importance of renewable energy installation rises. However, the load change is absorbed with expanding the wind power installation in the electricity system. So, Electric Power Company cannot help limiting the wind power installation from the viewpoint of the frequency change control. Agency for Natural Resources and Energy came up with the method in 2004 and reported that the use of the ream system line between electric power companies and output fluctuation relief by battery energy storage system are efficient measures. At the same time, Tohoku Electric power Company accepted wind power connected candidates with this technical requirement in 2006. Therefore, our company has developed a wind power generation system by optimizing wind turbine power limitation system and battery energy storage system, and we have evaluated that performance by our simulation. After that, we have constructed the Shiura wind farm with this system in Gosyogawara city since April 2009, and now, commercial operation started in February 2010. In this thesis, we introduce the outline of our system and we report the evaluation of the output fluctuation actual data in the Shiura wind farm.

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It is difficult for developing countries to introduce renewable energies such as wind and solar as actively as developed countries to reduce the carbon dioxide exhaust. Therefore, it is necessary to design wind turbine based on the appropriate technology concept for the developing country. The appropriate technology means; 1. low-cost, 2. simple design, 3. easy to construct using local materials, 4. possible to maintain and repair by local people. The authors experimented systematically in the wind tunnel using the model wind turbine with the bended-plate type Hades which could be easily introduced to developing countries based on the design concept of appropriate technology.

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In this study, two types of experimental wind turbines were tested to compare the performance at low tip speed ratio. One has a rotor with tapered blades designed by the combined blade element and momentum theory less than tip speed ratio 2. The other rotor has inversely tapered blades in which the calculated chord length are applied in an opposite way. Moreover, to analyze the behavior of the air flow around these rotors, the visualization test by PIV has also conducted.

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Wind turbine generation (WTG) has a major role in the world at present. The global wind market for WTG installations in 2009 was worth about 5.5 trillion Japanese Yen and around half million people are now employed around the world. WTG production by Japanese manufacturer in 2009 is about 1GW per year, which is about 2.6% of world share. In the meantime, WTG is made of about 10,000 parts, and most of those are purchased from outside companies. Therefore, wind industry has large economic effects. In Japan, there are more than 200 companies which are related to WTG. Furthermore, Japanese manufactures have strong competitive power in large bearings, generators and power device among the major components of WTG. The economic effect by Japanese WTG industry is estimated as 300 billion Japanese Yen and more than 5000 people employment.

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The Japanese wind power is now being watched with interest of the world, because the national target of wind energy is 3000MW that was proposed in the Primary Energy Supply Plan. In conjunction with these increasing, the power of each unit is also increasing. But the power trains of wind turbines have various kind of types because of the basic background of manufacturers histories. In this paper, I will deals with the general explanation of these power train systems and its facilities and futures. And we must give some consideration to durability, safety and a high performance for wind turbine industries and consequently these consideration will help the next generation wind turbine design and reliabilities.

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That is necessary efforts to reduce greenhouse gas pressing in the civilian sector, the unknown actual operation of energy systems of both supply and demand, not advanced energy efficiency that has not been established evaluation criteria clear that is present. In this study, we monitored both in supply and demand, by developing an evaluation method based on energy conservation monitoring systems have been proposed considering the matching of supply and demand of energy. In this paper, in small and medium size campus of Waseda University to investigate the actual situation of energy consumption, and consider the operation of the supply of equipment for heating, lighting and air conditioning made the proposal in the mixed energy even to the staff survey.

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A mechanically moving unit is prpposed for improving the performance of the desiccant air conditioning system. The desiccant unit is mechanically circulates between dehumidification zone and regeneration zone and the counter current contact type is possible. Axial distribution of relative humidity and temperature are measured in the fundamental experimental set up 50 mm in width, 2 mm or 5 mm in height and 312 mm in length. Change in the water content of the desiccant particles is measured based on the weight change of the desiccant container after the experiment. When gas flow rate was increased from 2 m/s to 8 m/s, dehumidification rate increases by 2.6 times. Required length of the dehumidification section is able to estimate based on the axial distribution of relative humidity.

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Reduction of CO_2 emissions and energy saving are the urgent issues for many fields of industries at present. Hot water, occupying considerable energy consumption rate in the whole industry, is generally generated using combustion gas being higher than 1,000 centigrade at boilers. However, the temperature loss is large at boiler process. Accordingly, we thought that energy saving could be accomplished if hot water could be generated using heat pumps. This presentation reports field test of a newly developed turbo heat pump for hot water in an actual factory. The heat pump is characterized by high efficiency and large amount of heat output, which equals approximately steam of 1,000 kg/hour, using turbo compressor. As a result of the field test, it was confirmed that the performance of the heat pump was the same as that of design.

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Comparative evaluation has been studied on energy systems to supply hot water for detached houses, which are CO_2 heat pump, small scale gas engine and polymer electrolyte fuel cell cogeneration systems together with gas fired hot water boiler with latest heat recovery. For energy demand data measured at 15 houses through one year, energy saving and CO_2 emission characteristics of systems are evaluated comparatively by applying mathematical optimization method. As the numerical result, it is concluded that CO_2 heat pump system has advantage of saving energy and of reducing CO_2 emission compared with other systems.

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To solve energy crisis and global environment problem, we must considerably improve the efficiency of energy systems. But recently, we can achieve high performance of each energy system. Therefore, from now on, we have to develop complex system and construct the total energy management system to optimize the system efficiency. To investigate these for the purpose of improving their efficiency, simulation is an effective way. However, simulation technology cannot be efficiently transferred to others because description method of the simulation code developed varies depending on the programmers. Thus, we have developed a general-purpose energy system analysis simulator called 'Energy Flow +M' and have confirmed that this software can be applied to various energy systems- the compression type heat pump, absorption heat pump and desiccant air-conditioning system. Energy Flow +M is just now open for the world through Internet. The address of the web page is http://www.ef-iae.com/index.htm.

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In order for economically viable distributed generation systems for apartment buildings to spread, it is essential to develop an efficient and low-cost heat supply system. We are developing a new cogeneration system (Neighboring CoGeneration: NCG). The key concept of this system is to install a heat supply unit with a hot water supply and a room heating function at each household and to connect different households by a single-loop hot water pipe. As a result, time leveling of the heat supply and heat transferring among households become possible. Thus, the costs of the piping and the heat source equipment decrease. Furthermore, because all the heat supply units store heat, the total heat storage capacity is large enough for cogeneration to generate according to the electricity demand and with high operating rate. In this paper, we reported the evaluation of the performance of the heat supply and the energy saving effect of NCG system for 50 households in winter by the dynamic simulation.

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This work aims to realize combined heat and power (CHP) system enhanced by chemical recuperation of the unused waste heat at around 300 degree C that is commonly found in many industries. This system can "upgrade" the unused waste heat to electric energy by endothermic reaction of DME steam reforming and can save the fuel consumption and reduce CO_2 emission. We successfully prepared the catalyst customized to this purpose. DME steam reforming is the sequential reaction which consists of DME hydrolysis and methanol decomposition or steam reforming, and a few research reported that solid acid promotes the former reaction. We experimented with several combinations of zeolite and γ-alumina for solid acid and CoFe-spinel, CuMnCrK, CuMn-spinel and LaPd/CeO_2 for the latter reactions. The test results showed that zeolite had higher activity for DME hydrolysis and LaPd/CeO_2 selectively produced CO by suppressing CO shift reaction at 300 degree C. The LHV of reformed gas increased by 8.7% compared to that of DME fuel.

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We developed GENEBO that is a gas fired water boiler which is partially driven by waste heat from the micro CHP whose electric power is 5 or 9.9kW. When installing micro CHP, you have to design to utilize the waste heat. And when using both waste heat from the CHP and heat from the boiler, it is not easy to give a priority to the waste heat. But with GENEBO, all you have to do is to install GENEBO and CHP. We also improved the boiler's partial load efficiency with proportional combustion control. At 30% load, GENEBO's efficiency is about 15% higher than conventional water boiler. GENEBO includes remote controller which shows you CHP's electric generation and CO2 reduction level besides water boiler's data such as hot water temperature. GENEBO's hot water output is 186kW, but you can connect two or three GENEBOs and use them as if it were one GENEBO. In this case, you can operate them with one remote controller.

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As the interest in environmental issues increases, the cogeneration system has recently been attracting much attention. Particularly, the use of gas engines for cogeneration systems with low emission and high thermal efficiency is now expected to become widespread. For improving thermal efficiency, it is necessary to extend the lean limit and accelerate combustion. In this study, attention was focused on "Pre-chamber Spark Plug", which has a pre-chamber at the tip of the standard plug. We studied the effects of using a pre-chamber spark plug for 300kW to 2MW gas engines with a single-cylinder test engine. By the pre-chamber plug, the lean limit was extended and the thermal efficiency was improved.

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DME (Dimethyl ether) has been investigated as a diesel fuel due to its high cetane number as same as light oil. On the other hand, micro cogeneration which is used a diesel engine cannot in a urban area as smoke density is high. Then, using DME with EGR can reduce NOx with lower smoke density because DME has an oxygen molecule. As heat value of DME is lower than light oil, injection duration is longer than light oil and thermal efficiency intends to be lower level. Lower temperature of EGR makes thermal efficiency improve. Micro diesel co-generation by using DME can be approval in urban areas.

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In this paper, a engine control system was built up and confirmed that enables combustion of arbitrary mixture of biogas and city gas 13A with high generating efficiency and low NOx. Biogas is stoicheiometric mixing ratio, then city gas compensates. Mixture of city gas 13A and biogas varies in stoicheiometric mixing ratio. Existing engine system can only control premixture fuel flow, so that it can't tackle variety amount of heat generation. Therefore other throttle to control fuel flow was added. Wobbe Index was used as a fuel index. Using Wobbe Index revealed relationship that targeted oxygen concentration in emission is conducted from generating efficiency and NOx. On the basis of these experiments, we have developed feed back control systems from oxygen concentration in emission. In a practice run, this control system could deal with variation of stoicheiometric mixing ratio or load.

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This paper describes the effectiveness of residential load following gas engine combined heat and power systems in cold regions for energy conservation. The numerical simulation on energy consumption of 35 residences in cold region showed the system reduced primary energy than conventional heating boiler or residential gas engine systems without load following. And then, we have installed 8 systems to residences in Sapporo area and collected operation data to confirm performances in general use. Results show the system have reduced 17 GJ primary energy and 1.2 ton CO2 on average from October 2009 to March 2010.

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To achieve a low-carbon society, we promote nuclear energy, which plays a zero-emission power generation. Therefore the nuclear power plants have been imposed a stable supply of electricity. The condition based maintenance (CBM) is effective in order to maintain a stable operation of the nuclear power plants. We built the performance diagnosis system based on the heat and mass balance calculation as one of supporting tools for the CBM. Moreover we note that the performance diagnosis system is built for steam turbine cycle operating with saturated steam conditions.

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This report introduces the operation examples of the real-time online data collection analysis system, which was developed originally. Some extremely effective functions included in this system, that is, double watch of central control room equipment, calibration watch of equipment set up on central post and each site, tuning of various static characteristics and dynamic characteristics, integrated checking of efficiency of system, and etc. were described with the operation case. In addition, possibility of application of this system to power plants, for instance, earlier detection of broken behavior change, trouble sign, and others were referred.

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Nuclear power plants are required to have especially high reliability and increasingly longer service life. As a contribution to the solution of these issues, troubles unique to nuclear power plants caused by two-phase flow of steam/condensate were identified through analysis from a new perspective on problem areas and causes focusing on the steam field using a database that tracks troubles at nuclear power plants. Additionally, useful technology for prevention against the effects of these troubles that occur in steam/condensate piping, such as erosion-induced pipe wall thinning and potential water hammer, are reported under the categories of 1) steam lines, 2) condensate lines, 3) measurement, inspection or monitoring of equipment or piping.

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In the nuclear power plants, many small-bore piping are frequently oscillated by vibrational sources like pumps, and it is important to evaluate vibration stress of the piping efficiently to prevent the fatigue failure. This study proposes a new method developed to calculate vibration stress using displacements measured by multiple contactless displacement sensors. In this study, the applicability of the proposed method was verified with vibration experiments by using an actual mock-up piping. The experiments were conducted under sweep operations or steady operations of rotation frequency of pump. The stress calculated by the proposed method was compared with the stress measured by strain gauge. As the results, the calculated stress was in good agreement with the measured stress though having some error which was negligible comparing to endurance limit of failure. Therefore, the method developed was applicable to measure vibration stress of small-bore piping in the actual plants.

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Specimens with diameters of 1 and 6 mm were prepared from an ASTM335 P22 main stream pipe that had been used over 300,000 hours in 568℃ environment in a power plant. Their creep properties were compared. Similar results have been obtained for creep time to rupture, elongation, and reduction of area. The creep time to rupture and minimum creep rate have similar linear relationship on the logarithmic plots for both specimens. From these results, creep testing on a miniature specimen (1 mm diameter) is considered effective for evaluating residual life of materials used in high-temperature environments.

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The small punch creep (SPC) test is possible to predict residual creep life at a high accuracy. But, the results of SPC tests cannot be compared with uniaxial creep or internal pressure creep results directly. In this report, the relationship between SPC test results and uniaxial creep test results in STPA23(1.25Cr-0.5Mo Steel) and STPA24(2.25Cr-1Mo Steel) were studied. The obtained relationship between SPC load and equivalent uniaxial creep stress of all materials formed a simple linear equation under the wide range of test temperature and test period. The relationship between SPC test results and internal pressure creep tests results was also studied. The creep life of internal pressure creep influenced material also showed good correspondence with SPC results. Therefore SPC can estimate the residual life of internal pressure creep influenced materials.

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Fatigue and creep damage of Ni-base superalloys have been investigated using the electron back-scattering diffraction pattern (EBSP) method. The damage caused by high temperature fatigue test is detected as misorientation, and localize at the surface of damaged specimens. The value of misorientation tends to increase with increasing the fatigue damage. Creep damage is also evaluated as the misorientation, but localized around grain boundaries and interfaces of precipitates. The misorientation has a good correlation with the creep strain. Among some misorientation parameters applied in this study, orientation distribution (OD) shows better sensitivity and relativity to the damage than the other misorientation parameters.

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"Research Committee on basic technology to improve pipe-wall-thinning management" was established on April, 2008, and the activity continued for two years. The objective of the research committee is to investigate new R&D studies in the world in order to improve the management due to revise and/or enhancement of the pipe wall thinning management rules of JSME. Researches for improving the management in the plant, the evaluation methods of flow accelerated corrosion and liquid droplet impingement erosion, inspection and monitoring methods of pipe wall thickness, criterion of pipe wall thinning from material strength, and evaluation methods of pipe wall thinning rate from the inspection data were investigated.

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Effect of wall thinning on the strength of elbow pipe was addressed. A testing system was developed to investigate the collapse load of elbow pipe subjected to the in-plane bending of closing mode under a constant internal pressure. The artificial wall thinning was introduced to the inner surface at extrados of elbow. The collapse load obtained as the maximum load from the fracture test was compared with the numerical results of the finite element elasto-plastic finite deformation analysis. However, the numerical results underestimated the maximum load, since the finite element analysis did not consider the effect of the thickness variation and strain hardening during the bending process to form the elbow from the straight pipe.

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This paper describes fracture behavior evaluation of wall-thinned pipes by image processing strain measurement system. Regular grids with nominal size of 10 x 10 mm were marked on the 100A carbon steel pipes and the images taken with 6 CCD cameras of 15 million pixcels were correlated to realize resolution of 0.3% strain. Strain of the cylinder outer surface was evaluated by 1) modeling the grids as a cylindrical shell, 2) measuring deformation of the grid on a projected plane, and 3) by applying updated Lagrangian method. The results indicate that the method is effective for analyzing fracture modes and fracture criterions.

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In the operation of electric power plant, it is necessary to understand the condition of the pipe quantitatively. The purpose is to prevent the accident caused of the wall thinning portion due to erosion or corrosion. The thickness of the pipe is partially measured with the ultrasonic thickness gage now. However, it is difficult to investigate the wall thinning portion in the pipe quantitatively without confirming it beforehand. In this study, to identify the location of thinning for the purpose, the ultrasonic testing system using the guided wave was developed, that was able to investigate partially the wall thinning portion of all aspects of pipe to be inspected at a time. This system propagates guided wave by using an electro-magnetic acoustic transducer. An efficient pipe investigation becomes possible because it widely understand the condition of the pipe by using this system. The reliability improvement of facilities and the reduction of maintenance and repairs are expected to be attempted. In this report the actual results of applying the ultrasonic testing system were developed.

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Electromagnetic acoustic resonance method (EMAR) has a high capability of evaluating thickness or ultrasonic velocity, and it is applied to the measurement of thickness, elastic constants, damping properties and so on. Since the principle of the method is based on the through-thickness resonances of bulk waves, that is, thickness oscillations, targets are usually limited to ones with simple geometry such as plates. In this study, pipe wall thinning, where the thickness changes on the curved surface, is evaluated by EMAR. For the purpose, several data processing methods are applied to extract thickness information from spectral responses. Measured spectra are obtained by an experiment using a carbon steel pipe with two-dimensional thinning machined by milling, and results of the data processing are compared in view of accuracy and stability. Finally, the data processing method is applied to the EMAR spectra of a pipe specimen cut from a mock-up test loop.

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A magnetic flux leakage (MFL) method must be an effective nondestructive evaluation (NDE) technique for the wall thinning in nuclear power plant, because this method has already been applied to industry field such as gas pipeline. A development of a probe feasible for piping and a feasibility study of MFL method for application in reinforcing plate in nuclear power plant are required for practical uses. Therefore, ancillary yokes are examined to adapt to the piping shape, and higher sensitivity was achieved to estimate depth in slit on piping. Additionally, steels superposed were prepared and a slit modeled wall thinning was formed on underlayer here, then, applicability of MFL method on the superposed specimen was investigated.

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