This paper focuses on knowledge coordinators as part of the knowledge transfer process in small-medium enterprises (SMEs). The findings of the analysis of 23 case studies and various coordination styles are presented. Within these. particular attention has been given to the symbiotic relationship between enterprises and graduate students. Among others. it is found that manufacturing companies. when in the process of knowledge research. acquire knowledge mainly through business transactions, but when in the need for innovative solutions, they tend to acquire knowledge from outer spheres. This is where graduate students can take responsibility.

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Apart from the double acting type engine, Stirling engines have either 2 pistons in 2 cylinders or 2 pistons in a single cylinder, with the heater, regenerator and cooler installed between the pistons. The single piston type Stirling engine, on the other hand, consists of a single piston in a single cylinder, a cooler, a regenerator, a heater and a gas damper. The gas damper has a role equivalent to the expansion piston. For this paper, a simple prototype engine, using air at normal atmospheric pressure as the working gas, was fabricated. In addition, as one of the performance improvements, the engine with a bypass tube, using a capillary tube inserted between the gas damper and cooler, was set up. The effect of the bypass on shaft power and P-V diagram was examined experimentally. As a result, a dramatic increase in the shaft power was achieved.

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The shaft power calculated using the Schmidt model and the mechanism efficiency determined applying SENFT theory have been used to obtains by an analytical method the optimal values, at which shaft work becomes maximum power ,of engine compression ratio and thermal ratio of a low-temperature difference Stirling engine. As a result, it was found that correlation at thermal ratio and compression ratio in low-temperature difference Stirling Engine.

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We are now planning and design a new a^+ -type engine that is considered about higher buffer pressure and higher engine speed. Note that the a^+ -type mechanism is suitable for low-temperature-difference Stirling engines and the a^+ -type engine has a displacer consisting of two pistons that are connected via rods. Therefore, it is possible to use a regenerator with a sufficiently large area within a small range of temperature difference and to suppress the load applied to the crankshaft. The a^+ -type engine is most effectively applied to power generation using solar heat or combustion heat from a wood biomass because the engine can be driven by indirect heating using 300 degC thermal oil. We report the plan and design of new 10 kW class engine that reduces volume of half, increases thermal efficiency from 12% to 16%.

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The species of working gas greatly influences the performance of Stirling engine. The superiority of hydrogen and helium with light molecular weight has been confirmed experimentally. In thermoacoustic engine which resembles Stirling engine, the mixed gas is the optimum for the working gas, and the mixed gas of helium and argon is used. In this study, the effect of mixing ratio of helium and argon on the Stirling engine performance is examined experimentally in order to examine the possibility of the application of mixed gas to Stirling engine. As the result, though the indicated power increases with the increase of mixing ratio of argon to helium, the buffer loss also increses and the brake power decreases.

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We had developed and designed original gamma-type circulating flow stiffing engine (CFSE) with two lead valves in operating gas flow, for application of waist heat recovering. Meanwhile, present CFSE prototype has new pulse converters in substitution for the lead valves. Though the pulse converters are incomplete preventing reverse flow compared with lead valve, they are simpler, low pressure loss and wide section area. A method of pulse converter, valve less design applied for present CFSE with two-cylinders, 600W electric output by linear motor- generator, and prediction of the performance in low temperature differential cases are introduced.

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Recently, the today in which people cry for global environmental problem and global warming countermeasures are necessary. The effective utilization of waste heat is also tremendous with energy saving techniques in order to reduce CO_2. It uselessly discharges waste heat such as automobile,ship,factory to the system which high-density energy. The Stirling engine is a optimum engine as the system which recovers this waste heat. In this paper, we develops the 100W engine of the prototype for the purpose of the development of 1kW small temperature difference Stirling engine which made factory waste heat to be a target. The simulation carried out theconceptual design considering the pressure loss. The result showed that the indicated power of 350W was obtained in buffer pressure 1MPa and 0.418 thermal ratio.

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A 5kW class Stirling engine generator has been developed with the aim of constructing a system mainly for business use. The Stirling engine is built up as a 2-piston type with driving mechanism. It has a hot cylinder and a heat-exchanger cylinder in which a regenerator and a cooler are installed, and the both cylinders are connected by a heater made by U-shape tubes. The developed Stirling engine generator is unified hermetically because of including a PM synchronous generator in the driving mechanism. From the results of performance test, maximum electric power attains 4.95kW. And also, heater layout is improved as the heater tubes with fins are perpendicular to combustion gas in a square shape duct, so that thermal input into the engine increases.

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Gases burn more efficiently than solids, gasification is used for generating energy from wood pellets Electricity can be generated cleanly by a Stirling engine driven by the heat energy obtained through gasified combustion, along with a cogeneration system, without emitting surplus CO2 into the atmosphere. This study examined the basic combustion characteristics of a wood pellet gasified combustor for a Stirling engine and the performance of a Stirling engine cogeneration system with a wood pellet gasified combustor. A gasified combustor was built, and the combustor temperature and concentration was measured to study the combustion state. As a result, it was revealed that a gasified combustor was suitable for use with a Stirling engine because its exit temperature was higher than that of an ordinary updraft-type combustor. Our prototype combustor was capable of supplying a maximum 18.5KW to a Stirling engine using 23.8KW of fuel, resulting in a heat-to-fuel capacity of 78%.

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Koichi HIRATA, Yoichi NIKI and Masakuni KAWADA, National Maritime Research Institute, Tokyo The authors had developed a marine heat recovery system with Stirling engine generators. In the research project, three experimental Stirling engines were developed. The marine heat recovery system had carried to a ship for field test. After the field tests on the ship, an endurance performance of the Stirling engine was measured and estimated with 3000-hour operation in our laboratory. In this paper, the results of the endurance test are described.

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SATOYAMA CLUB demonstrated of a new energy system aimed for utilization of the woody biomass such as the thinnings or the pruning branches in the Expo '70 Commemorative Park (Suita-shi, Osaka) from 2005. And, in SUCTION, the development of the indirect heating type Stirling engine that used a heat medium for the heat transportation is occurred for many years, and good result is provided by the development of I kW and 10kW class engine using a heat source of 300 degrees Celsius. From 2008, the cogeneration system which combined the lkW class engine and a woody biomass boiler is examined, and demonstrated now in the Expo '70 Commemorative Park. The present result of the demonstration is reported

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Wastes are defined as a new energy and desired to utilize an energy source beneficially. The authors pay attention to better utilization of wastes, which is a method to convert wastes into energy, and present a waste incineration and power generation system constructed by an incinerator and a Stirling engine generator. The incinerator has a maximum incineration capacity of 49kg/h and is cooled by circulating water in the side walls in order to enable a long life and supply heat by a hot water or air flow. The Stirling engine generator is installed in a secondary combustion space of the incinerator and heated by combustion gas and an auxiliary kerosene burner. In order to demonstrate the power generation and the heat supply, a test using woody biomass as fuel is carried out at a greenhouse tomato plantation in Hokkaido. From the test results, the system showed the electric output of 3.2kW and heat supply of 47kW, and practicability of the waste incineration and power generation system is verified.

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Woody biomass such as the thinned wood is widely distributed in the mountain-ringed region and the field, and it is difficult economically to collect and to transport it. Therefore, small-scale power generation is suitable in many cases. Development of small-scale power system based on the biomass gasification is under going. But because of so complicated system and high cost, the commercialization is not progressing as expected. Small-scale system which has high thermal efficiency and low cost is requested. So, in this study we develop small-scale power system, in which stirling engine power system is combined with biomass combustion furnace. We aim at high thermal efficiency and low cost of the biomass power system through this developmnet. In this paper, our field tests of a 30kW-class stirling engine is reported. Moreover, the demonstration plant of stirling engine system using biomass is intrduced and typical results of the field test of the plant are reported.

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The green house effect by carbon dioxide issue would make better recognizing the importance of efficient use of energy in terms of high energy conservation measures. Accordingly, attention is drawn to the Stirling cycle machine, which is a perfect freon free and efficient machine. Most Stirling engines operate in temperature ranges in which the temperature difference between the heat source and heat sink is between 100 K and 700 K, with the room temperature being at the lower end of the operating temperature range. However, information available on engines that utilize the room temperature as the heat source and the ultra-low temperature of liquid nitrogen as the heat sink is scarce. Engines that operate within such temperature ranges are called cryogenic heat engines. If their practical applications are realized, energy that has hitherto been wasted during the use of ultra-low-temperature media can be recovered in the form of electrical energy. We have designed and developed a 500 W class Stirling machine as a cryogenic engine. This paper presents some operating characteristics.

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In a small-scale LNG (Liquefied Natural Gas) satellite station, a lot of cold energy is released to atmosphere when the LNG is vaporized. In order to use the cold energy effectively, we have discussed to apply a cold energy used Stirling engine generator. As the first step for the application, we operate a Stirling engine with liquid nitrogen in our laboratory. In this paper, we show the construction of the experimental Stirling engine, and report detailed experimental results of the engine using the liquid nitrogen.

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The authors are studying generation from hot water and latent heat of LNG in a LNG satellite facility. The latent heat of LNG consumes about 280kWh in the LNG satellite facility of vaporization value 2t-LNG/h. The Stiring engine can obtain electrical power using the latent heat of LNG. A LN_2 vaporization test system was made using a 20W Stirling engine. In this test, data of Stirling engine operation and LN_2 vaporization for basic study was obtained. The balance operation condition of steady state vaporization and Stirling engine operation was confirmed in this experiment. In this paper, the experimental results at vaporization test system using Stirling engine are described.

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This paper deals with heat transfer due to a periodic annular jet from an annular channel in the displacer induced by its reciprocal motion. Heaters are concentric strips of nickel foil each temperature of which is kept constant using a CTA system. When the reciprocal frequency is low, heat transfer is higher near the top dead center of the displacer i.e. the clearance between displacer and the cylinder end is small. As the frequency becomes higher, heat transfer due to the jet from the annular channel becomes predominant in the impinging region and among the phases (from top dead center) from 30° to 210°. Heat transfer in such region and phases is proportional to frequency to the 0.75th power and pressure to the 0.75th power. Heat transfer is correlated in dimensionless forms not only for phase and area averaged values but also for the impinging region and for phases while the jet enhances heat transfer.

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This Stirling refrigerator only imparts a light load to the global environment because it does not use fluorocarbon refrigerants. To put the Stirling refrigerator into practical use at room temperature, a smaller sizing and higher efficiency are essential. In this study the authors have thus contrived an active-type regenerator, and have actually designed and manufactured a new experimental model. The authors have grasped the operating characteristics of the Stirling refrigerator with an active-type regenerator and will then report them herein.

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The 20K-class Double-staged Stirling cooler is a key cryogenic technology for cooling the optical detectors and telescopes of the highly-sophisticated astronomy satellite missions proposed by JAXA, for instance, the x-ray astronomy mission Astro-H(2013) and the cryogenic infrared telescope mission SPICA(2018). Therefore, it is required that the advanced double-staged Stirling cooler with improvement of mechanical reliability and cooling performance will be developed, based on the existing one onboard the first Japanese infrared astronomy mission Akari(2006) with cooling power of 200mW at 20K (90W power input). This paper describes about development status of the advanced double-staged Stirling cooler with cooling performance and long lifetime test.

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We made a single piston-type Stirling engine. It is composed of only one piston and regenerator matrix in a cylinder. We succeeded in the improvement of the performance of the single piston engine with mixed pore size regenerator in consideration of the gas flow in regenerator.

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Trial production of the Stirling engine car has worked aiming at the held Stirling engine techno rally in November every year. The mechanism of Stirling engine was understood from producing the a type and the 13 type Stirling engine car and various processing technologies established it. However, the problem and the friction problem etc. of the design problem and the material option of the transmission mechanism etc. of power were clarified as the hardship and the car until operating as an engine, too. It wants to institute these problems, and to get the instruction of the cause investigation from various seniors preferably.

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The oscillating velocity due to an acoustic wave was measured with hot wire anemometer. The measured velocity was compared with the velocity obtained by using two-sensor method. It was found that the velocity measurement with hot-wire anemometer needs the correction factor for velocity amplitude and phase.

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We built a prototype thermoacoustic Stirling engine that consisted of a looped tube and a mechanical (damped) oscillator. From measurements of the acoustic impedance of the acoustical part and that of the mechanical part as functions of temperature and frequency, we present that the self-sustained oscillations occur at the temperature and frequency at which these acoustic impedances mutually agreed. This result gives an experimental method for predicting the oscillating frequency and the hot-end temperature required for steady oscillation in thermoacoustic systems.

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Thermoacoustic apparatus is attracting attention as a technology for next generation that aims effective utilization of exhaust heat from a motorcar or a factory in recent years. In this research, we produce a simple loop-type thermo-acoustic engine, and aim to take in the fluid condition, effect of DC flow and influencing factor to the performance. And we grasp basic characteristics to construct the high efficient and in-car equipment.

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The simplified thermoacoustic sound wave generator, 72mm in radius, 860mm long, was employed for precisely measuring oscillatory flow in the resonance tube including neighboring its wall. The calculation software, Mathematica, was used for simulating oscillatory flow both in the resonance tube and in the stack. It is confirmed that the Richardson effects exist and the simulated results of velocity change and phase differences between pressure and velocity qualitatively agree with the experimental ones. The optimum stack size, which has been ensured by the past experiments, is also re-ascertained by radial velocity distributions and so on simulated by its software.

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To what extent can we lower the onset temperature ratio (OTR) to start a thermoacoustic engine? We tried to answer this question by installing a secondary regenerator in a travelling wave engine consisting of a looped tube and a branch resonator. Factors governing the OTR were studied experimentally through measurements of the quality factor at various temperature ratios. Installation of the secondary regenerator at a suitable position drastically enhanced thermoacoustic effects while introducing a slight damping to the system. As a result, the OTR of the present thermoacoustic engine was decreased from 1.76 to 1.19, when the regenerators were increased to five.

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A thermoacoustic engine consists of a working gas, a regenerator, heat exchangers, and an acoustic resonator. When the temperature ratio of the two heat exchangers exceeds a critical value, the engine converts heat into acoustic power. One of the most important scales in a thermoacoustic device is the length of its resonator, which in this study, the effect of the change of the resonator length on the critical temperature ratio is addressed.

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We designed and built a multistage thermoacoustic Stirling engine electric generator prototype. Use of three regenerators aligned in series, not in parallel, makes it different from ordinary Stirling engines. The prototype thermally amplifies the input acoustic power through the Stirling thermodynamic cycles and converts the amplified acoustic power into electricity. Although the gain of acoustic power was 1.76 with a single regenerator, it reached 5.1 when three regenerators were used. The Stirling engine that we developed can function at a low temperature differential.

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A cascade thermoacoustic engine driving an alternator was numerically designed. It was composed of five regenerators, and one alternator that convert acoustic power to electric power. The acoustic power generated in one regenerator was amplified by four regenerators, and then, it was absorbed by the alternator. When the working fluid is 0.5MPa nitrogen, and the cold and hot temperatures of heat sources are 300K and 450K, respectively, the designed thermoacoustic engine can supply the acoustic power of 53W to the alternator with a thermal efficiency of 0.03, corresponding to 11% of the Carnot efficiency.

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To produce a miniature thermoacoustic system, experimental investigations of the prime mover's performance characteristics were conducted using a miniaturized thermoacoustic system. A straight-type thermoacoustic system's total length was changed. Then measurements of the sound field in the system were conducted on each system. Results show that the distribution of phase difference between sound pressure and particle velocity accord when the system is miniaturized. Moreover, results confirm that the distribution of sound pressure accorded with the total length. A functioning straight-type thermoacoustic system with 130 mm total length was designed based on experimental results. Its operation shows successful conversion from heat energy to sound energy.

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