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Koji YAMAGUCHI, Takamitsu SATO, Toshiya NANAHARA, Shigeto HIRAI, Masaa ...
Article type: Article
Session ID: 2421
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Wind power generation in Japan has shown marked increase in recent years. From a power system point of view, since a wind turbine is an intermittent generator with large output fluctuation, increase of wind turbines causes considerable concerns on their adverse effects on power quality such as frequency and voltage deviation. Especially in wind farm, additional factors inherent to wind farm are expected to affect the fluctuation of its power output along with the output fluctuation of a single wind turbine. Because most of the output fluctuation arises from that of inflow wind for each wind turbine, modeling wake flow is indispensable in order to estimate the output fluctuation of wind farm. In this study, rotor wake of a wind turbine was examined both in field measurement and wind tunnel. Experimental expression for wake radius, velocity deficit, and turbulence intensity in a wake region is obtained with the results from these measurements.
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Shinji ARINAGA, Masaaki SHIBATA, Shigeto HIRAI, Toshiya NANAHARA, Taka ...
Article type: Article
Session ID: 2422
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Recently, wind power generation has shown marked increase also in Japan. From a power system point of view, since a wind turbine is an intermittent generator with large output fluctuation, increase of wind turbines causes considerable concerns on their adverse effects on power quality such as frequency and voltage deviation. Because of this, we carried out the research which power output fluctuation characteristics of wind farm were estimated in detail. The most important subject of this research was to estimate precisely the wind velocity that it flows in to the wind turbine. Therefore, wind measurement, wind turbine operation measurement and wind tunnel experiments were done, and by analyzing those data we developed the method that the 3-D velocity of the wind that it flows in to each wind turbine inside wind farm was estimated. Specially, power output fluctuation characteristics in column wind were examined in detail.
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Hironori HAYASHI
Article type: Article
Session ID: 2423
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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The CFD-based wind simulation model "LAWEPS" for wind farm siting was developed through four year (FY1999-2002) project of the New Energy and Industrial Technology Development Organization (NEDO) and now its production has been widely utilized through NEDO web site or distribution at actual cost This paper introduces the outline and some practical applications of the LAWEPS.
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Seiichi ARIGA, Chuichi ARAKAWA, Makoto IIDA
Article type: Article
Session ID: 2424
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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The authors have measured wind at two points near the wind turbine site since April 2002 and acquired data for another site in Tokyo bay. To estimate wind flow over Tokyo bay area. MM5 model was used to simulate wind flow around Tokyo bay area up to resolution of 1 km. CFD simulation reads the result from MM5 model as initial and boundary condition and execute simulation with higher resolution. Pseudo-compressibility method and Spalart-Allmaras turbulence model was selected for compatibility with simulation of flow around wind turbine. Comparison between measured find velocity and result from pseudo-compressibility method showed good agreement over result from MM5 simulation.
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Toshihiro INOUE, Satoshi OKAMURA, Makoto IIDA, Chuichi ARAKAWA, Takao ...
Article type: Article
Session ID: 2425
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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This study is aimed to properly assess the Renewable Energy especially wind power generation by "SeeD Model", the dynamic integrated assessment model proposing we developed. For proper assessments, we updated the assessment of Offshore wind turbine technology which calculates the resource of wind power, and included the learning curb which price the power rates. Thus, we concluded the possibility to achieve the goal the ministry set that wind power capacity should be 3GW by 2010. Also we remarked the high rate growth of wind power and fuel cells which Energy-economic simulation proved with the learning curb.
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Kazuyoshi FUSHINOBU, Daishi TAKAHASHI, Ken OKAZAKI
Article type: Article
Session ID: 2426
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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We have demonstrated the operation of a PEFC cell with Ti thin-film gas diffusion layers (GDLs.) The thin-film GDL has been fabricated by using photolithography technique with RIE to create micro-through holes for materials transport. Both temperature and through hole diameter effects have been examined to compare with conventional carbon based GDLs. The thin-film GDL can be a tool for investigating the concentration overpotentials in PEFCs.
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Hiromitsu MASUDA, Kohei ITO, Takashi MASUOKA, Yasushi KAKIMOTO
Article type: Article
Session ID: 2427
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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When PEFC is operated at high power, a drop of water is appeared in the channel and the gas diffusion layer. And then the gas supply is blocked, and the cell voltage decreases and becomes unstable. So we are developing a numerical code considering gas-liquid two-phase flow to elucidate the problem of water to PEFC. In the numerical model, mass and momentum conservation were considered two-dimensionally. Especially in mass conservation, the water vapor condensation was considered when the vapor pressure exceeded the saturation vapor pressure. In this report, we show the outline of the code and an example of the calculation result.
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Kazuhiro TERANISHI, Shohji TSUSHIMA, Katsuhiko FUKUZATO, Shuichiro HIR ...
Article type: Article
Session ID: 2428
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A water transport analysis has been developed and used to investigate the water distribution in the polymer electrolyte membrane for the polymer electrolyte fuel cell. In this article, we introduce the maximum water content value for the PEM, and water transport constant for the cell, based on the experiment respectively. The analyzed water distribution of a PEM at various operation conditions is consistent with that of the previous MRI measurement.
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Shohji TSUSHIMA, Kazuhiro TERANISHI, Shuichiro HIRAI
Article type: Article
Session ID: 2429
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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In this article, we examined an effect of liquid water supply to a polymer electrolyte fuel cell membrane on membrane hydration and cell performance, because the membrane is to be swelled by means of direct contact with liquid water and thus improvement of cell performance can be expected. We assembled a fuel cell with liquid water feed for magnetic resonance imaging (MRI) measurement and measured water content distribution in the membrane under fuel cell operation with liquid water supply. It was revealed that supplying liquid water to the membrane improved cell performance. MRI result clearly shows that liquid water supply enhanced membrane hydration, resulting in reduction of electric resistance of the membrane.
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Naofumi Nohara, Tomohiro Ogawa, Kazusige Kikuta, Takemi Chikahisa
Article type: Article
Session ID: 2430
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A fuel cell was made to allow direct observation of the phenomena and 2-D temperature measurement in cathode channels. The experimental results showed production and flow of liquid water in the cell, and there was good correlation between area covered by condensing water and cell voltage. The experimental results also showed that uniformity of the contact pressure strongly influenced the temperature distribution. Experimental setup was made to measure local current distribution, and it was recognized important to develop a method to compensate the effect of local resistance change due to inserting the measuring probes. The paper proposes an unique method to correct these effect to determine actual local currents.
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Ryuichiro GOTO, [in Japanese], Yasuhiro HAMADA, Makoto NAKAMURA, Hidek ...
Article type: Article
Session ID: 2431
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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This paper describes performance evaluation of a polymer electrolyte fuel cell for applying to the demonstration on hybrid utilization of renewable energy and the fuel cell for a residential energy system. First, experiments of characteristics on heat and power generation were carried out Direct current electrical efficiency and the heat recovery efficiency at a rated output operation were quite high; 42.5% and 49.2%, respectively. Second, characteristics of partial load, water temperature for heat recovery, start-up time, load following and exhaust gas were clarified.
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Zhili CHEN, Yasuyuki TSUTSUMI, Kenichi HASHIMOTO, Mitsuru KONNO, Susum ...
Article type: Article
Session ID: 2432
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A simulation and experimental study was carried out for estimating the performance of an DDFC (Direct Dimethyl Ether Fuel Cell) exhaust gas recovery system which was designed for abstraction of DME (Dimethyl Ether) from CO_2 in DDFC exhaust gas and recirculation of DME to the cell by dissolving DME into water. The simulation results show that the recovery ration reached to 80% with a DME oversupply ratio of 150% and a solubility of DME to pure water of 5wt.%. The simulation results also show that an equilibrium beteew water comsurption for fuel humudification and water production by water generationg reaction in cathode side could be kept at the temperature of recovery system <48℃. The experimental results show that the cell output current increased when the exhaust gas was absorbed by water and the absorbent wasrecycled.
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Mayumi OGAWA, Mitsuru KONNO, Zhili CHEN, Yasuyuki TSUTSUMI
Article type: Article
Session ID: 2433
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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The solubility of dimethyl ether (DME) in water was investigated, as the base data for developing an DDFC (Direct Dimethyl Ether Fuel Cell) exhaust gas recovery system. The equilibrium vapor pressure and liquid compositions were measured at the DDFC working conditions of temperature of 50 and 80 ℃ .The results of the experiments were compared with H.Holldorf's data.
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Sangkyun PARK, Kazushige KIKUTA, Takemi CHIKAHISA, Yukio HISHINUMA
Article type: Article
Session ID: 2434
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A free-breathing polymer electrolyte membrane fuel cell (PEMFC), whose oxidant is fed by natural convection from ambient air, is considered as one of small and portable power sources. In this study, the performance limit without gas humidification and the factors affecting performance of the free-breathing PEMFC were investigated. The cell voltage of normal PEMFC without gas humidification is approximate equivalent of that with gas humidification under low current density conditions, less than 0.1 A/cm^2. For the performance of the free-breathing PEMFC at the low current density, the contact resistance loss between separator and gas diffusion layer is dominant factor and the separator structure for decreasing the contact resistance is needed to improve performance.
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Hiroyasu KIMURA, Naoki SHIKAZONO, Nobuhide KASAGI
Article type: Article
Session ID: 2435
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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In the present study, numerical simulation of thermal and electrochemical fields of planar SOFC has been performed. Effects of cell aspect ratio, oxygen utilization, cell division and steam reforming on temperature field and output power were investigated. It is demonstrated that short cell length in air flow direction and short steam reformer are recommended for designing small temperature variation cell.
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Takafumi NISHINO, Hiroshi IWAI, Kenjiro SUZUKI
Article type: Article
Session ID: 2436
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Effects of inlet temperature and flow rate of air on the cell thermal field of an indirect internal reforming tubular solid oxide fuel cell (IIR-T-SOFC) have been examined by using a quasi-three-dimensional numerical model previously developed. In this model, multicomponent thermo-fluid fields and electric potential/current fields in the cell are simultaneously treated with consideration of reforming/electrochemical reactions. As a result, it was shown that lower air inlet temperatures reduce the overall cell temperature while larger air flow rates effectively reduce the maximum temperature and temperature gradient of the cell.
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Takashi ONO, Akira Kokaji, Yoshihide Ohshima, Takashi Shigehisa, Narut ...
Article type: Article
Session ID: 2437
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Since 2001 Kyocera corporation has been developing 1kW class Solid Oxide Fuel Cell (SOFC) power module. A conceptual design was conducted to achieve high electrical efficiency. To achieve this aim, the SOFC power module has stacks of SOFC cell of high power density for high fuel utilization. The module is operated thermally self-sustainable. We developed a flat tube SOFC cell, which has high power density performance, and can be manufactured by low cost process. The developed SOFC cell stack has shown high fuel utilization performance. We also developed a new conceptual SOFC power module. This module has high efficiency heat exchanger for high thermal energy efficiency. This module structure enables thermally self-sustainable power generation at high electrical efficiency. As a result, we achieved 1200W(DC) electrical power at 48%HHV(DC, 54%LHV) electrical efficiency.
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Aina MORITA, Shinji KIMIJIMA
Article type: Article
Session ID: 2438
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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In this paper, the energy-supplying capacity optimization of the cogeneration system based on a micro gas turbine (μ,GT)-solid oxide fuel cell (SOFC) hybrid system is discussed. The cogeneration system consists of the hybrid system, waste heat recovery devices and air-conditioning equipments. The power output capacity of the hybrid system is set in the range of 100kW to 800kW, because the floor area of a target building (hotel) is fixed at 7000m^2. Typical time-series energy demand data and the climate condition data in Tokyo are also used in the calculation. In consequence, the fuel consumption is approximately minimized at the power output capacity of 300kW. At this optimal capacity, the hybrid system should be operated under the partial load condition in order to follow the fluctuation of the electric power demand. The reduction of the fuel consumption becomes about 57% of a conventional energy supply system, and the energy cost saving is simultaneously reached to be almost 60%.
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Osamu AZEGAMI, Iwao AKAIDA, Kazuhiko ITO, Shinichiro HIGUCHI
Article type: Article
Session ID: 2439
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A pressurized Molten Carbonate Fuel Cell (MCFC) / Micro Gas Turbine (MGT) hybrid system has been developing to demonstrate high efficiency and very low NOx and SOx emission. The 300kWe MCFC / MGT hybrid Co-generation system is in test at the TOYOTA Environmental Center. An inferred system efficiency has been nearly achieved, and this system has been possible to operate with no firing of MGT combustor in the range of 75% to 100% load. The developed MGT and control method of this system are focused in this paper.
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Chiyuki NAKAMATA, Youji OOKITA, Kazuyoshi CHIKUGO, Fujio MIMURA, Masah ...
Article type: Article
Session ID: 2501
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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For a turbine cooling air reduction, an integrated impingement and pin fin cooling configuration was developed. This configuration integrated impingement cooling and pin fin cooling devices into one body, aiming at an enhancement of the effective heat transfer area. Not only a cooling performance improvement but also an establishment of manufacturing process and keeping sufficient strength and life are the subjects of this research. A staggered type cooling configuration was designed to get better cooling performance in manufacturing limitations. A cooling performance test was conducted, and it was confirmed that a heat conductance enhancement factor for a cooling air side surface of a staggered type specimen was 1.2-1.3. And the staggered type gave superior cooling performance over the conventional type that had no pin, for given pressure drop. An actual size staggered type specimen was successfully manufactured. A fatigue test was also conducted, and it was confirmed that there was no higher stress concentration in a staggered type specimen than that in a conventional type specimen.
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Kazuyoshi FUSHINOBU, Daishi TAKAHASHI, Ken OKAZAKI
Article type: Article
Session ID: 2426
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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We have demonstrated the operation of a PEFC cell with Ti thin-film gas diffusion layers (GDLs.) The thin-film GDL has been fabricated by using photolithography technique with RIE to create micro-through holes for materials transport. Both temperature and through hole diameter effects have been examined to compare with conventional carbon based GDLs. The thin-film GDL can be a tool for investigating the concentration overpotentials in PEFCs.
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Toshihiko TAKAHASHI, Kazunori WATANABE, Takayuki SAKAI, Takeshi TAKAHA ...
Article type: Article
Session ID: 2503
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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The present paper reports on a numerical analysis of a temperature distribution of a rotor blade in a gas turbine, which has ribbed serpentine passages for internal cooling. Three-dimensional steady-state numerical analysis was conducted by thermal conjugation of inside and outside fields of the blade, which consists of convection heat transfer around the blade, thermal conduction in the blade material and internal blade cooling. In order to evaluate heat transfer in the internal cooling passages, correlations derived from calculations of convection in the ribbed passage were applied. As a result, predicted temperature profile on the blade coincides with the distinctive features on real blades, which are due to damages by oxidation, and that predicted temperature profile is in agreement with local wall temperature estimated on the basis of the material of the real spent blade.
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Norio OHIWA, Hirofumi HATTORI, Mitsuru KOZUKA, Yasutaka NAGANO
Article type: Article
Session ID: 2504
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Turbulence model has been improved so far for analysis of a turbulent flow with rotation. In particular, a modified nonlinear two-equation model was proposed, with which rotating channel flows with spanwise rotations were predicted very accurately. Recently, rotating channel flows with arbitrary rotating axes have been investigated by direct numerical simulation (DNS). Although a knowledge of spanwise rotating channel flow has been accumulated, there are few reports on streamwise and wall-normal rotating channel flows. In the present study, based on our DNS databases of streamwise and wall-normal rotating channel flows, the existing nonlinear two-equation heat-transfer turbulence models were evaluated. And using the results of evaluation, we improved the modeled expression of turbulent heat-flux for heat transfer in flows with arbitrary rotating axes.
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Hiroyuki SATO, Tadaya NAKAJIMA, Takahisa NAGAO, A. Koichi HAYASHI, Sat ...
Article type: Article
Session ID: 2505
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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This paper describes results of experiments on combustion control systems for the suppression of combustion oscillation. Considering the thermo acoustic effect, secondary injection system was applied to reduce the pressure oscillation and combustion noise. In this study, both fuel and air injection systems as the secondary injection were carried out As the results, in the case of fuel injection, the main flame was anchored with lift-off and then the pressure oscillation was suppressed. However, NOx level was increased. In the case of air injection type, both the pressure oscillation and the NOx level were decreased. Furthermore, it was found that flame-holding technique with the super-lean combustion could be established using the secondary air injection system.
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Masato FURUKAWA, Isao TOMITA, Takurou KAMEDA, Kazutoyo YAMADA, Masahir ...
Article type: Article
Session ID: 2506
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A transient phenomenon of rotating stall inception in an axial compressor was investigated by unsteady three-dimensional Navier-Stokes flow Simulation. This simulation has captured vertical flow structure at rotating stall inception. It was found that the spiral-type breakdown of the tip leakage vortex at near-stall condition and leading edge separation-Type stall inception occurred. In comparison with casing wall pressure distribution, this result was similar to experimental result using 'Synchronous Field Measurement' with time interpolation. Therefore, it shows that RANS flow simulation has high accuracy for the transient phenomenon, and it was able to predict the rotating stall inception.
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Kouji ISHIHARA, Hoshio TSUJITA, Shimpei MIZUKI, Atsumasa YAMAMOTO
Article type: Article
Session ID: 2507
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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The increase of blade loading of a turbine cascade makes it possible to reduce the number of blades and stages, and consequently to decrease both the weights and the costs for manufacturing and maintenance. However, the strong secondary flow appears in such highly loaded turbine cascades due to the high turning angles and reduces the efficiencies. In the present study, the effects of the tip clearance size(TCL) on the aerodynamic performance of a stationary linear ultra-highly loaded turbine cascade(UHLTC), which will be used for the future gas turbine engines of hypersonic transport, were investigated numerically.
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Ken-ichi FUNAZAKI, Kazutoyo YAMADA, Arisa ITO, Toshiaki IKOHAGI
Article type: Article
Session ID: 2508
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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In this work, we made an attempt to optimize the blade profile in a high-load LP turbine. Multi-Objective Genetic Algorithm (MOGA) was used as the optimization technique. For the two target functions, we employed the total pressure loss and the weight of the LP turbine. These target functions were evaluated from the 2D calculations, which were performed using commercial software, CFX5. In the calculations, the computational grid was generated automatically from the blade profile using the bezier curves.
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Takayuki MATSUNUMA, Hiro YOSHIDA, Yasukata TSUTSUI
Article type: Article
Session ID: 2509
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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Blade Reynolds numbers for the turbine stage of small and micro gas turbine engines can drop below 10^5. At these low Reynolds number conditions, the boundary layer is dominated by laminar flow and is susceptible to flow separation, which is associated with increased loss and reduced performance. This paper describes the effect of boundary layer trip on an annular turbine cascade under very low Reynolds number conditions, Re_<out>= 4.4×10^4〜22.8×10^4. The free-stream turbulence intensity was varied between 0.5% and 8.9%. The velocity and turbulence intensity at the exit of the turbine cascade were measured using a single-element hot-wire anemometry for both "with trip" and "no trip" blades. Effect of the trip was concentrated at the blade hub region because of the three-dimensional flow fields. The effect of trip gradually decreased with increasing turbulence intensity.
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Junichi KAZAWA, Toshinori WATANABE
Article type: Article
Session ID: 2510
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A flow-structure coupled numerical method was developed to study the possibility of active control of cascade flutter. With the intention of applying piezo electric device, numerical analyses were performed under transonic flow conditions. In the cascade model adopted for this study, the unsteady aerodynamic force induced by passage shock wave was dominant for blade vibration stability. To control the passage shock movement, the method in which the trailing edge of blade was actively vibrated was sought. The method was revealed to change the unsteady aerodynamic force acted on the blade from exciting force to damping force if the phase of trailing edge oscillation was properly selected. To confirm the possibility of active control of cascade flutter, on/off control method with trailing edge oscillation was numerically simulated by flow-structure coupled method. From the results, it was revealed that increase in blade amplitude was suppressed by this control.
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Shijie GUO
Article type: Article
Session ID: 2511
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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This paper demonstrates the investigations on the blade vibration of a radial inflow micro gas turbine wheel. Firstly, the dependence of Young's modulus on temperature was measured since it is a major concern in structure analysis. Secondly, turbine blades suffer many excitations during operation, such as pressure fluctuations (unsteady aerodynamic forces), torque fluctuations, etc. On the other hand, a turbine wheel has many kinds of vibration modes, typical ones being blade-hub (disk) coupled modes and blade-shaft (torsional) coupled modes. Model experiments and FEM (Finite Element Method) analysis were conducted to study the coupled vibration and to identify the modes, which are more likely to cause problems. It is demonstrated that Young's modulus depends on temperature greatly and the dependence should be considered in structure analysis. Anisotropy and scattering of the Young's modulus were not significant even at high temperature. The results of model experiments and FEM analysis show that torque fluctuations and uniform pressure fluctuations (the fluctuations acting on all the blades in the same phase) may excite resonance of blade-shaft (torsional) coupled modes. Impact excitations and propagating pressure fluctuations (the fluctuations propagating in the circumferential direction around the blades) may excite blade-hub (disk) coupled modes.
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Hideo YOSHIDA, Hideomi ISHIBE, Hiroki MATSUI, Takeshi EGAWA, Satoshi Y ...
Article type: Article
Session ID: 2512
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A hybrid gas bearing with water evaporation from ultra-fine porous medium is newly proposed. The proposed bearing is considered to be applied to microturbines and have mainly three advantages suitable for the applications. The first is the stability improved by water evaporation from ultra-fine porous medium. The second is the effective lubrication by liquid water at start and stop of the journal rotation. The third is the cooling effect on the high-temperature journal due to water evaporation. A preliminary experiment is conducted, and the stable start and stop of the journal rotation are confirmed.
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Yutaka Sakurai, Rie Shirakawa, Yutaka Koizumi, Toshiharu Kobayashi
Article type: Article
Session ID: 2513
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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National Institute for Materials Science has been developed several Ni-based single crystal superalloys for a gas turbine aiming at improvement in thermal efficiency .This project attained the heat resistance of 1100℃ which was a target at last recently. In this investigation, high temperature Young's modulus of each generation's alloy developed until now was measured by the ultrasonic method and resonance method. Thus, it was clarified high temperature Young's modulus measurement of an ultrasonic method has large variation compared with the resonance method. The variation in a measurement result is a gap of the crystal angle of a specimen. When [011] direction of a crystal shifted 23degree, it turns out that a Elastic modulus value changes about 9 %.
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Hiro YOSHIDA, Takayuki MATSUNUMA, Norihiko IKI, Yoshio AKIMUNE
Article type: Article
Session ID: 2514
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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A primary operation tests using a desktop size gas turbine has been successfully carried out. In the first step of the tests, we have concentrated ourselves on the operation at elevated temperatures. Thus the duration of the bench test at each rotation speed was set to be 1 minute. The baseline machine is J-850 (Sophia Precision, Co.,Ltd.) originally made for model airplanes. In this study, we replaced an INCONEL 713C alloy turbine rotor with 5.5 cm diameter into a type SN235 ceramic rotor (Kyocera Corporation). Mixture of 70% white kerosene and 30% gasoline was used as the fuel. The running test was made at the rotational speeds up to 140,000 r.p.m. in the atmospheric air. The basic performance of the small gas turbine with ceramic rotor was tested.
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Yoshinobu MORI, Yuichi MIYAMOTO, Kazuya MATSUO, Dai HASHIMOTO, Kenji M ...
Article type: Article
Session ID: 2515
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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We propose a new control method for an absorption chiller-heater with a compact gas turbine generator and an exhaust re-combustion burner. This absorption chiller-heater is driven by heat power of the burner for re-burning exhaust gas of the gas turbine generator, and all or a part of its electric power consumption can be supplied from the gas turbine generator. Therefore, the control system is required cooperative control functions, for example, added fuel rate control, sensible heat quantity of exhaust gas, generating power, exhaust gas composition, and so on. In this paper, we describe a configuration of this control system, simulation and actual examination results.
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Sachio Tachibana, Takanobu Yamada, Hiromi Isitani
Article type: Article
Session ID: 2516
Published: September 04, 2004
Released on J-STAGE: August 01, 2017
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This study shows the performance of co-generation system operated by micro gas turbine (MGT) in a snowy and cold area. In the experiment it was clarified that the characteristics of generating efficiency, heat recovery efficiency, and the other parameteres were obtained under lower ambient temperatures. As the results, generating efficiency increased with the decrease of the temperature and the co-generation system could operate smoothly although the ambient temperature reached downward to -20℃. It was also found that the exhaust energy from the system became significantly effective to a snow melting equipment and bio-gas plants in public facility, as the practical applications.
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