Advanced IGCC was planned by using exergy-recuperation concept. Advanced IGCC achieve high efficiency by the gas purification at high temperature and the autothermal reaction in the gasifier. The increment of the efficiency IGCC to the standard case is about 4% by applying autothermal reaction in the gasifier. This system requires the extra heat supply in order to hold the autothermal reaction condition in the gasifier. Therefore the increment of the gross efficiency by applying autothermal reaction is only 1% (HHV). The gross thermal efficiency of 1500 degree C class Advanced IGCC is 53.3%(HHV) i.e. 5.3% (HHV) higher than standard case. When turbine inlet temperature increase from 1500 degree C to 1700 degree C, the gross thermal efficiency increases from 53.3% to over 57% (HHV) and it is about 59% (HHV) when the adiabatic efficiency of compressor and high temperature turbine increase 5points.

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Combustion properties of coal gasification gas with CO_2 dilution were investigated for a newly proposed IGCC power generation system with CO_2 capture. In this system, the gasification gas was burned under high CO_2 concentration atmosphere. The laminar and turbulent burning velocities were measured for outwardly propagating stoichiometric H_2/O_2/CO_2 flames at the mixture pressures of 0.10 to 0.50MPa. The unstretched laminar burning velocity, u_l and the Markstein number were smaller than those of H_2/O_2/N_2 flames. The ratio of the turbulent burning velocity at the flame radius 30mm, u_<tn(30mm)> to u_l was larger than that of H_2/O_2/N_2 flames. Increase in the turbulence Karlovitz number and decrease in the Markstein number by the CO_2 dilution might cause the increase in u_<tn(30mm)>/u_l of H_2/O_2/CO_2 flames.

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Coal gasifier which produces the syngas is an important part of the IGCC plant. Models of the coal gasifier for the process modeling of the IGCC plant are typically developed based on heat and mass balance and equilibrium calculations. An upgraded gasifier model is proposed with an aim to incorporate the coal kinetic rate characteristics. Three steps of coal gasification, devolatilization, homogeneous reactions, and heterogeneous reactions are considered. Importance of coal devolatilization as the initial step in coal conversion makes its understanding essential in the optimization of processes and the development of pollution control strategies. Homogeneous and heterogeneous reactions are considered with reactivity of coal or char. Because these reactions progress simultaneously, they are dealt with by explicit method for numerical analysis. For the gasifier efficiency, carbon conversion and cold gas efficiency are defined and calculated.

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This research develops an energy-economic model with endogenous technological change. This model assumes a decrease of specific capital cost and O&M cost from technological change, and considers that technological experience is shared among the same component technologies. Furthermore, feasibility of CCS in Japan's electricity sector is analyzed. The analysis is performed based on scenarios with alternative assumptions over technological change of CCS component technologies; carbon capture, transport, and injection technologies. As a result, technological change doubles CCS potential, and generation technologies with CCS can produce 10% of total power generation in 2030. In addition, CO_2 reduction from CCS introduction is increased by half, and 16% of carbon emissions in 2030 are reduced. CCS introduction increases the total system cost by 3%. Technological change has little influence on the total system cost. Aggressive R&D effort for CCS might push reduction by 20% of carbon emissions in 2030.

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A systematic evaluation of design alternatives for oxy-coal power generating plant with carbon dioxide capture and storage (CCS) capability is presented. This study is performed along with the retrofitting attempt of the existing 125MWe coal firing power station of Young-Dong (YD) station of Korea South-East Electric Power Company. Evaluation cases are selected for comparison, namely the base case of original plant, a case of retrofitted boiler with existing steam-power generation block, a case of optimized oxy-PC power plant. Comparative evaluation is based on the system of individual blocks, including air-gas block, water-steam side block, air separation unit (ASU) and carbon dioxide process unit (CPU) blocks. A system of independent blocks as well as a system of cross-linked blocks is considered. Thermodynamic analysis included the thermal efficiency to power generation, the exergy analysis based on the second law and sensitivity analysis to impurities in the system including the purity of oxygen, air ingress into the oxygen-combustor, and unwanted gaseous components of nitrogen, argon and oxygen in ASU and CPU.

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IGCC is expected to expand fuel for power generation and to reduce carbon dioxide emission. Therefore it is important to establish and expand the way to reuse IGCC slag, coal ash from IGCC power station, as a resource. Focusing on foaming characteristic of IGCC slag, we succeeded in establish the way to control bulk density of slag balloon precisely and find out promising technique to promote foaming of IGCC slag. And the possibility was found that ultra light-weight slag balloon from IGCC slag can substitute expanded obsidian as material for soil drainage improvement or green-roof. Production cost of ultra light-weight slag balloon is expected as much lower than market price of expanded obsidian.

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Component level models are frequently used to simulate the performance of gas turbines. Precision of these models are dependent on the performance map of the components, such as compressors, turbines and combustors. Difference between the simulation results and the field data can be ascribed to the deviation of the component maps. Shape similarities of component maps are observed so linear scaling factors can be used for correction. A method of adaptive modeling of gas turbine engine by scaling component map is discussed in this paper. The adapting method is composed by two nested parts. The inner part is a steady state model solved by matrix iteration algorithm. The outer part is a determination process of scaling factors solved also by matrix iteration algorithm. As a demonstrative example, a three spool gas turbine is simulated and its model is corrected by matching simulation results with field data.

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The cooling effectiveness of gas turbine blades by film cooling was examined. Air at 420 K flowed in the rectangular test flow channel of 60 mm wide, 60 mm high and 350 mm long. Air at room temperature for the film cooling flowed into the test flow channel through a hole at the bottom. The effect of the shape of the effluent hole for the cooling flow on the cooling effectiveness was examined. The shapes examined were circular and oblong-circular. The effect of mist introduction into the cooling flow was also examined. Experimental results were analyzed with the STAR-CD code. Since the film cooling flows from the oblong-circular holes spread wider than from the circular hole, better cooling effectivenesses were maintained in the wider area in the cases of the oblong-circular holes than the case of the circular hole. In the case of the circular hole, the flow separation occurred near the effluent flow hole, which resulted in the lower cooling effectiveness than in the cases of the oblong-circular holes. The deterioration of the cooling effectiveness occurred in the larger effluent flow in the case of the circular hole. Results of the STAR-CD analyses proved that the vortex that existed at the edge of the cooing film flow and rolled the main flow into the cooling film was kept farther away from the center of the cooling film and made weaker in the oblong-circular hole case than in the circular hole case. These might result in the better cooling effectivenesses in the cases of the oblong-circular holes. The introduction of mists into the film cooling flow produced the remarkable improvement of the cooling effectiveness. It might be caused by a decrease in the temperature of the cooling film and an increase in the velocity of the cooling film flow due to the evaporation of the mists.

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To understand the mixing phenomena of film cooling air with mainstream is very important to attain higher film cooling performance. This paper describes the detailed mixing mechanism of film cooling air with mainstream using a low-speed wind tunnel. The three different shaped film cooling holes and a conventional circular hole were used in the experiment for comparison. The time-mean and instantaneous fields of velocity and film cooling effectiveness were measured in high resolution by PIV and LIF, respectively. The experimental results show that fine vortex structures are formed in the shear layer between film cooling air and mainstream. Numerical simulation has been also conducted to examine detailed mechanism of the mixing process, using Detached Eddy Simulation (DES). The DES revealed that pre-mixing of coolant jet and mainstream occurs inside a shaped hole (c), which has relatively long and deep diffused exit. This leads to deterioration of film cooling effectiveness at the downstream.

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This study deals with the investigation of thermal and aerodynamic performance of film cooling over the leading edge of a high-pressure turbine blade for gas turbines. A large-scaled test model of a typical leading edge with cooling holes is constructed by use of acrylic-resin semi-circular cylinder and flat plates to obtain experimental data. In this study, film effectiveness and heat transfer coefficient over the leading edge are measured by a transient method using thermochromic liquid crystal, where the secondary air is heated. As for the film effectiveness, a comb-like thermo-probe consisting of a number of thermocouples is also employed to acquire the quasi-adiabatic wall temperature as well as spatial distributions of the secondary air temperature on each of the traverse planes normal to the model surface. The steady-state flow field around and inside the test model, including the plenum chamber, is reproduced by RANS (Raynolds-Averaged Navier-Stokes) solvers. A commercial CFD solver, ANSYS Fluent, is used in this study. DES (Detached Eddy Simulation) based on Spalart-Allmaras model is also applied to the simulation. Film effectiveness distributions are numerically investigated using RANS and DES approaches and compared with the experiments. It follows that DES shows better agreements with the experiment than RANS simulation.

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The Double-Jet Film-Cooling (DJFC) technology is invented by the authors and comprises a significant enhancement of the adiabatic film-cooling effectiveness due to the formation of anti-kidney vortices. The DJFC technology places a second ejection hole with compound angle in a double-hole arrangement downstream the first hole. The second hole creates a second jet with another dominating vortex rotating in opposite direction to the first one and then combines both jets to one jet (or double jet). The basic applicability and function of the DJFC technology has been proven by the numerical studies and testing in a test rig. The comparison of the experimental results of the adiabatic film cooling effectiveness to the numerical results for the same blowing ratio (e. g. M=0.5; M = (p * C)_c/(p * C)_h) shows qualitatively similar distributions. However, the experimental results show enhanced mixing-out of the cooling air and, thus, the experimental values of the adiabatic film cooling effectiveness are lower compared to the numerical values.

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The high temperature gas turbine with high loaded turbine cascade is under development to prevent the global warming effect by the carbon dioxide and to save natural resources. The larger loss at the high loaded turbine cascade is generated by the secondary flow including horseshoe vortex. In this research flow visualization and the loss measurement were carried out to understand the behavior of the horseshoe vortex and its effect on the loss. The internal flow measurement showed that the loss increased greatly toward the trailing edge of the blade suction surface root. The suction surface fins were tested as a countermeasure and proved to reduce the peak loss of the secondary flow.

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Endwall heat transfer characteristics of inclined pin-fin array channels have been investigated to improve the cooling efficiency of gas turbine's combustor liners. The time-mean local Nusselt number profiles were obtained by naphthalene sublimation technique based on the heat/mass transfer analogy. Three kinds of angled pin-fins (-45, 0 and +45 degrees) were tested and compared with each other. As a result, the average heat transfer coefficient on the endwall of normal pin fins was higher than that of the angled pin fins. However, the total amount of heat transfer is expected to be increased by inclined pin fins because the total surface area is about 1.4 times larger than that of normal pin fins, and the pressure loss in angled pin-fin channel was smaller than in the normal pin-fin channel.

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If the turbine inlet temperature (TIT) of gas turbine exceeds 1000℃, attaining 35% efficiency becomes promising. Silicon nitride ceramic is well known as a typical material for hot components of the gas turbines. In utilizing ceramics as the hot components of gas turbines, foreign object impact damages are the main issue in the ceramic engines. In this study, we examined the critical impact velocity, which resulted in the fracture of the ceramic test pieces. In the experiment, a 1 mm diameter samarium cobalt ball impacted on the type SN282 (Kyocera) silicon nitride ceramic test piece. The test piece was hold under the actual service condition, i.e. the elevated temperatures and the pre-loading tensile loads pertinent to the centrifugal force. The main results so far obtained were: Both the elevated temperature and the pre-loading stress decreased the critical impact velocity lower than that under the room temperature without stress. The effects of the temperature and the stress on decreasing the critical velocity were not simply additive.

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A large-eddy simulation of coal combustion on a pulverized coal combustion furnace with a complex swirl burner is performed and validated by comparing with the experiment in this study. Unstructured grid system is employed to apply LES to the practical complex geometry burner. The motion of coal particles is calculated by the Lagrangian method with the parcel model. The direct closure SSFRRM (Scale similarity filtered reaction rate model) is used as a turbulent combustion model. The results show that a recirculation flow is formed in the downstream central region of the burner and its region varies dynamically due to the turbulent mixing with the axial direction flows. Comparisons of the axial distributions of time-averaged gaseous temperature and oxygen concentration shows in general good agreement with the experiment results, although the distribution of NO concentration which is relatively minor to the major species in the combustion is not in agreement with the experiment result very much. It is confirmed that the basic combustion characteristics can be captured and the capability of the LES of coal combustion field is well demonstrated in this study.

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It is very important for China to reduce the consumption of petroleum under the pressure of its fundamental realities of lean-oil--rich-coal and the consistently increasing price of international crude oil. For this reason, we developed series of minimal-oil igniting burners applied on the boilers in power stations to reduce the oil consumption for ignition. The most significant characteristic of the burners is the average igniting-oil reduction by over 95%. This superior performance can be assured by some built-in igniting oil nozzles and by some novel designs for the burners' cooling. The application of this technology on a 600 MW unit shows the igniting-oil consumption reduced from 631 tons to 11 tons. Up to now, the technology has achieved remarkable success on over 50 power units in China.

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A three-dimensional numerical simulation of the flow, combustion, heat transfer and NOx formation process is applied to a 1MW pulverized coal furnace with two swirl burners oppositely installed at the front and back walls. Different cases as varying the coal properties, coal concentration bias and air supply are simulated in detail. Comparisons of simulation and experimental temperature distributions are conducted and the results show that the numerical and experimental results are consistent generally. Air supply has obviously influence on combustion characteristics and the ratio of inner and outer secondary air is a key factor for air staged combustion. The fuel rich/lean combustion can significantly reduce the NOx emission, however the injcetion position for the fuel rich stream must match the recirculation zone.

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The laser-induced ignition gathers attention as the relatively new technique of ignition owing to its flexibility of ignition point that could be of benefit for security and combustion efficiency in the lean premixed combustion. In this study, the laser-induced ignition phenomenon is investigated experimentally, especially on the relation between the temperature of the premixed gas and the minimum ignition energy. Methane/air mixture is used as the premixed gas. The initial temperature of premixed gas is varied from 296 K to 450 K at the same number density of molecules. Results clearly show that the ratio of absorption to the plasma increased with the increase of the initial temperature of premixed gas. In addition, the minimum ignition energy decreased with the increase of initial temperature of premixed gas. Eventually, it improves the ignitability of premixed gas by the laser-induced ignition.

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The sol-gel citrate method and the co-precipitation method are industrially practical technique to synthesis perovskite for methane combustion. In the present study two methods were compared with respect to their activity for methane combustion. XRD, SEM and TG-DSC were used to characterize the catalysts. The results show that the citrate method was more promising than the co-precipitation method. Higher purity, more uniform and finer particle, lower formation temperature and higher activity are achieved by the citrate precursor. In the co-precipitation method, the convertional oven drying and supercritical drying sample achieves similar catalytic activity for methane combustion.

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In recent years, the high enthalpy value of the fuel combustion has been studied by a number of investigators in some specific conditions. A novel liquid-metal combustion system involving the reaction of lithium (Li) and sulfur hexafluoride (SF_6) can release a lot of heat in a short time and is also known as the SCEPS (Stored Chemical Energy Propulsion Systems). Li/SF_6 Chemistry Heat Source System can provide heat to specific heat storage equipment, which can be a heat source of AMTEC (Alkali Metal Thermal to Electric Converter). AMTEC is a novel method of energy conversion, which is researched by many individuals and institutes. This paper researched on Combustion Flow Field in Li/SF_6 Chemistry Heat Source System. Used limited velocity chemical reaction model to simulate the process of physical and chemical, applied RNG k-ε and EDC model to calculate turbulence combustion flow. Through simulation, it obtained the character of flow field and the distribution of the products in 10 seconds and the affection of different conditions of mass flux and initial temperature, which provided a new way to study the combustion flow field in the Chemistry Heat Source System.

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To improve radiation emission characteristics of a single-layered porous burner, the heat-recirculating porous burner constructed by two sections of porous materials with different porosities and pore per inch (PPI) were investigated experimentally and theoretically. The improved porous emitter or the second section was installed downstream of a single-layered porous burner (first section) in which dividing distance between two surfaces of porous materials was restricted at 30 mm. As this structure of the present burner, a multi-layered porous burner is defined. In the analysis, the energy liberation due to combustion and the effects of radiation were considered in the energy equations for the gas and solid phases. We assumed that the chemical kinetics of gas-phase reactions were governed by a single-step Arrenius rate expression of methane-air premixed combustion. To evaluate the radiative transports in the solid-phase energy equation, the P_1 approximation was used to solve the equation of transfer for the radiation field in the porous burner and porous emitter. Ni-Cr open-cellular porous material, where porosity and PPI are 0.93 and 21.5 respectively, was selected as a porous burner, and three kinds of Ni-Cr open-cellular ones with different physical characteristics were used as the improved porous emitters. Radiant output from the multi-layered porous burner was measured based on a two-color radiometry. Comparison between predicted and measured results of the forward radiative heat flux and the porous surface temperatures were satisfactory agreement: the validity of the present theoretical model for predicting the radiation from the present porous burner was confirmed.

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Co-firing of Municipal Solid Waste with coal is an attractive option for their disposal. Hydrothermally treated MSW blends of various proportions (on %wt), with coal were tested in a Thermogravimetric Analyzer. The result of this work indicates that the blending of MSW with low rank coal enhances the ignition of coal. But the co-firing characteristics of MSW and coal blend cannot be predicted only from the pyrolytic phenomena as the other factors such as the energy content of the individual blend fuel also play vital roles in deciding the blend co-firing characteristics. The combustion characteristics of blends followed those of parent fuels in both an additive and non-additive manners. However, the effects of MSW blending in smaller than 20% were hardly noticeable and the blend fuel behaves similar to coal. This result shows the feasibility of using MSW with coal in the present combustion facility without major modifications.

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Addition of coal into the biomass gasification as an auxiliary or backup carbon resource was proposed to maintain the economical scale of treatment. The gasification performance of combined wood powder and pulverized coal was examined in the lab-scale test furnace of the down-flow entrained bed. The wood powder sieved under 200 μm and bituminous coal pulverized under #200 mesh were used as a combined fuel sample and fed pneumatically with nitrogen into each different burner set on the top of the furnace. Oxygen was supplied as the gasification agent. The maximum temperatures in the furnace were over 1500 K, but were not beyond the fusion temperature of coal ash, 1700 K. This temperature region is essentially important to allow the fly ash captured in the down-flow of the entrained bed without slag yield. The carbon conversion to gas achieved at higher efficiency than 80-90 percent although the residence time of gas-solid flow in the furnace was as short as a few seconds. The slag formation of coal ash was not observed at the temperatures in this work.

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The effects of three factors on combustion performance of petroleum coke, Hejin Coal and Shenmu Coal has been compared, including the ratio of primary air, excess air factor, and the swirling intensity of outer secondary air. The experiments were carried out on a one-dimensional furnace with dual channel swirling burner, in which temperature of center furnace, emission of air pollutants, and burn-out rate of fuel were measured. The results provide the optimal ratio of primary air, excess air factor and swirling intensity of outer secondary air for the fuels. The combustion performance of petroleum coke B is much better than petroleum coke A, but worse than Hejin coal and Shenmu coal. In addition, the burn-out rate of petroleum coke depends much more on the temperature in terminal stage of combustion than in the early stage of combustion.

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Soot formation characteristics of PME liquid fuel are investigated experimentally. The effects of droplet size distribution on soot formation characteristics are focused in this study. The droplet size distribution is controlled by using a vibratory orifice atomizer. A laminar counterflow spray burner is utilized as the combustion field. The soot formation characteristics of PME are measured by Laser Induced Incandescence (LII) and Time Resolved LII. Results show that the soot volume fraction increased with the increase of mean droplet size of PME fuel spray. It can be considered that the increase of the penetration and the decrease of evaporation rate associated with the increase of the mean droplet size of fuel spray, are the main reason of this inclination. In addition, soot formation is locally suppressed at the center of spray flame. These inclinations are similar to that of the hydrocarbon liquid fuel (n-dodecane) that has smaller molar weight than that of PME, since PME has oxygen in the molecule.

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Tunable Diode Laser Absorption Spectroscopy (TDLAS) technology is an ideal method to detect trace gas quantitatively based on the wavelength tunable character of diode laser. It can obtain the absorption spectroscopy in the characteristic absorption region. It can be used for trace gas detection and industrial combustion control due to its advantages of high sensitivity, high selectivity, quick respond and on-line measurement. Simultaneous measurement of O_2 concentration and temperature in combustion environment has great significance for improving combustion efficiency and reducing pollutants emission. A pair of O_2 absorption lines location at 13150.19cm^<-1> and 13160.34cm^<-1> was selected for measuring. Absorption line in 13150.19 cm^<-1> is selected for concentration measurement because of bigger line-strength. By detection of the background absorption simultaneously, the effecting of the O_2 in air atmosphere can been remove. O_2 concentration and temperature is simultaneously measured on high temperature test bench in laboratory based on TDLAS. Experimental results show that when concentration of O_2 higher than 2.5%, within the temperature range from 373K to 723K, the calculation error of concentration and temperature were below 4% the results coincide with calibration value. Simultaneous measuring of O_2 concentration and temperature has been done on an oil burner, the result proves that this method can be used on combustion environment.

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To understand SO_2 oxidation mechanism in boiler furnaces and to examine its factors quantitatively, the effects of coal type and combustion stoichiometry on SO3 formation have been investigated by conducting tests at 1.6MWth pilot plant having a test section simulating a horizontal tube bank. SO_3 concentration was high for coals containing high amounts of sulfur and vanadium oxides. SO_3 concentration decreased linearly with decreasing O_2 concentration. Reduction of combustion stoichiometry from 1.5 to 1.2 decreased SO_2 oxidation rate from 1.4 to 0.6% and from 2.4 to 1.0% for high sulfur coal and 40% petroleum coke blend, respectively. Our results are consistent with some field data and also significant for quantifying the effects of operating conditions on reducing SO_3.

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Diesel oil was used as the liquid fuel and the packed bed spheres were used as the porous medium. As different from the conventional open spray flame burner, the fuel was supplied dropwise to the top surface of the porous medium and burnt on the bottom side, where the swirling combustion air mixed with the fuel vapor. The pebbles, which were carefully chosen in the same size like the solid sphere homogeneously, had been adopted and used as the porous medium. The combustion behavior and the evaporation mechanism of the porous medium burner were investigated by measuring the profiles of temperature along the burner length as the axial temperature profile. The pollutant emission characteristics were also examined at the burner exit. The combustion, for the low emission of pollutants, was stabilized in the region of an equivalence ratio of 0.29 to 0.51 with the fuel input load of 4.01 to 5.11 kW. The effects of various parameters comprising equivalence ratio, fuel input load and porosity of the porous media on the combustion behavior were clarified. Practical applications and the future improvement of this type of the porous burner were also discussed.

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Numerical simulations of combustion optimization under multi-operating modes have been performed for a 600 MW tangentially coal-fired super-critical boiler. Under rated boiler load, the computational combustion efficiency of pulverized coal of 99.5% and nitrogen oxides (NOx) emission less than 400 mg/Nm^3 (6% O_2) agree well with the experimental data. For the high combustion efficiency of pulverized coal and low NOx emission, some combustion optimization information should be conducted as follows: (1) A double V-shaped (DV) secondary air distribution mode and more under fire air (UFA) are recommended. (2) The air flow of separated over fire air (SOFA) is not less than 75% of designed value. (3) The tilting angle of SOFA burner in horizontal direction is bigger than zero degree. (4) Under the load of 450MW, the lowest four primary air burner nozzle layers are recommended to be in service. (5) Under the load of 300MW, the intermediate three primary air burner nozzle layers are recommended to be in operation.

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Evaporation and combustion characteristics of a single aqueous glycerin solution droplet suspended in an electric furnace were investigated as a fundamental study for spray combustion of glycerin. The furnace temperature was changed between 280℃ to 900℃. Diameter of suspended droplet was around 2.6mm. Effects of furnace temperature and glycerin concentration on evaporation and combustion rate constants were investigated experimentally. Moreover, the viscosity of aqueous glycerin solution was measured to discuss its atomization characteristics. It was shown that the evaporation and combustion rate constant of glycerin solution droplet decreased with increasing the water content in glycerin solution and the rate of 90wt% glycerin droplet was similar to that of JIS C heavy fuel oil. As for the viscosity of aqueous glycerin solution, the value of 90wt% glycerin was much lower than that of JIS C heavy fuel oil. From these results, 90wt% glycerin solution was probably used as substitution for JIS C heavy fuel oil.

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This paper presents the experimental detections of the combustion process in a 300 MW arch-fired boiler burning a low quality coal. Visualizations of two-dimensional (2-D) temperature distribution in the furnace based on a novel flame image processing technique have been carried out. The detections have been the first time to perform on this type of boiler. The average temperature and emissivity of the flame have been calculated along the height. The results indicate that the flame center, which should be generally designed to locate in the lower furnace center, shifts upward close to or into the upper furnace above the arches. It shortens the running distance of the flame in the lower furnace and is unfavorable to the burnout of the pulverized coal. The flame emissivity decreases with the increase of the burnout degree of the pulverized coal along the furnace height.

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The possibility of wear reduction to the injector nozzle and of fuel leakage reduction from the injector is examined by using fatty acids and polymer type additives. The newly developed wear test equipment is used because of the implementation of an actual injector and DME as a fuel. A HFRR (High Frequency Reciprocating Rig) is also used to select a suitable concentration of additive. As a result, the blend additives are effective for reducing wear at the needle tip and decreasing the possibility of leakage to almost nothing from the injector. Furthermore, the effect of the impurities in DME is also examined in this study. A result shows the corrosion is caused by impurities of Methanol and water in DME.

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The repairing and strengthening of steam eroded turbine blades by laser direct metal deposition (DMD) forming technology were researched in this article. Based on the numerical calculation method of finite element, primary technology parameters of DMD were simulated. The microstructure and properties (such as hardness, anti-abrasive) of test specimen of repaired and strengthened blades were tested. The repaired layer has excellent bonding with substrate. The microstructure of repaired layer is typical cellular dendritic including (Fe,C,Cr) supersolubility solid solution and the interdendritic CrC. The microstructure of hardened layer consists (Fe,C,W,Cr) supersolubility solid solution and (Fe,C,W) eutectic. The average hardness of repaired layer and strengthened layer are HV_<0.2>350 and HV_<0.2>800 respectively, while the hardness of substrate is HV_<0.2>250. The anti-abrasive properties of repaired specimen and hardened specimen increase one time and three times than the substrate, respectively.

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Piping and heat exchangers are some of the major equipments at process plants. Over time, these equipments are subject to aging related problems, which are mainly caused by scale adhesion and erosion-corrosion. The former decreases flow rate, pressure, and heat transfer performance, while the latter leads to breakage of pipes and heat exchanger tubes. Therefore, the purpose of this study is to develop a diagnostic method of diagnosing pipe thickness with a differential pressure transmitter. In this paper, the diagnostic method of diagnosing pipe inner diameter in a water line is developed experimentally. The method is based on the phase of the transfer function of the downstream pressure to upstream pressure at the test section. The experimental results show that this method is able to diagnose the inner diameter of straight pipes given any flow rate.

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The Kansai Electric Power Co., Inc. (KEPCO) and Mitsubishi Materials Corporation (MMC) have been undertaking joint study of intermediate temperature solid oxide fuel cell (IT-SOFC), which can operate at between 600 and 800℃. IT SOFC of KEPCO and MMC is characterized by metallic separators, seal-less structure for the stack, flexible arm structure for the separators and highly conductive lanthanum gallate-based oxide for the electrolyte. The development of 10 kW-class CHP (Combined Heat and Power) system under a project supported by New Energy and Industrial Technology Development Organization (NEDO) was started in FY2004. In FY2007, the 10 kW-class CHP system gave the electrical efficiency of 41% HHV on AC output of 10 kW and the overall efficiency of 82% HHV when exhaust heat was recovered as 60℃ hot water. And two long-term field tests for 3,000 hours were carried out in FY2007 and 2008.

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The reaction characteristics of direct carbon fuel cell (DCFC) were investigated experimentally by controlling button cell temperature at 750〜900℃ and carbon fuel temperature at 800〜950℃. The polarization curves, electrochemical impedance spectra and anode gas compositions were measured during testing. The results showed that raising the temperatures of both button cell and carbon fuel can improve the performance of DCFC significantly. By increasing the carbon fuel temperature, the gasification reaction rate of carbon fuel can be accelerated and the polarization of DCFC can be reduced. The gasification of carbon fuel was the limitation factor of DCFC performance. The ohmic resistance and the activation polarization decrease with increasing of button cell temperature. The carbon deposition has been observed after testing, which can be reduced at higher temperature according to thermal dynamic analysis. In addition, it was deduced that the disordered carbon in carbon fuel is more active from Raman spectra.

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This work presents a one-dimensional distributed parameters mathematical model for MCFC based on mass, energy and momentum conservation principles and thermodynamic properties. The Model of electrochemical reaction has been considered based on the polarization characteristics from experience. Using the V-R modeling technique the partial differential equations for cell mass and momentum balance can be changed to ordinary differential equations which meet the quick simulation. The model is validated over experiments by the polarization curves when operating in different pressure and temperature. By comparison a systematic discrepancy between the experimental and theoretical cell voltage was observed. The difference can be probably caused by the existence of parasitic currents between electrodes, depending on specific cell manufacturing features, which are difficult to be evaluated. The average absolute difference between model prediction and experimental results is limited to 3% for cell voltage. The results indicate that the V-R characteristic modeling technique is valuable and viable in the MCFC system.

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With the aim of saving energy, reducing the environmental burden, conserving fossil oil and other depletable fuel resource, RTRI (Railway Technical Research Institute) is developing railway vehicles powered by fuel cells. We have already developed a 100 kW class fuel cell system and mounted on our test railway vehicle together with a high pressure (35 MPa) hydrogen cylinder system, etc. We carried out a running test of this fuel cell powered test railway vehicle at a test track laid in RTRI yard. In order to evaluate the running performance at higher vehicle speeds, we carried out a simulation running test on a rolling stock test plant. Based on those test results, we evaluated the fuel consumption rate (7.6-34.6km/kg-H_2) and efficiency (as high as 50 %). Now, we are developing fuel cells - lithium-ion battery - hybrid system for railway vehicles.

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Water management is very important in the development of the Polymer Electrolyte Fuel Cells (PEFC) with high performance and high reliability. Experimental and three-dimensional numerical studies have been done for the different type of flow passages of the PEFC. It is found that the separator rib plays as the covering to reduce the escape of water from the GDL to the channel. The moisturizing effect in the straight-type channel is better than that in the serpentine-type channels, but the draining effect in the serpentine-type channel is better than that in the straight-type channel.

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In this study, water behavior in an operating PEFC was visualized by using neutron radiography, and the cell voltage and the pressure drop between inlet and outlet of air were simultaneously measured. The PEFC is compliant with JARI (Japan Automobile Research Institute) standard PEFC. Electrode area with 50×50 mm^2 was visualized, and the cell temperature was kept at 80 ℃. The effect of geometry, i.e. single-serpentine and three-serpentine, relative humidity of air and current density were investigated. From the experiments, it can be confirmed that fluctuation of area-average water thickness in three-serpentine channel is larger than that in single-serpentine channel and water in the channel is likely to accumulate at corners of the channel in single-serpentine channel. Furthermore, movement of condensed water is strongly related with the cell voltage and the pressure drop.

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Water management in cathode electrode of polymer electrolyte fuel cells (PEFCs) is essential for high performance operation. The objective of this study is to understand the water transport phenomenon in cathode gas diffusion layer (GDL) of PEFCs by both experimental visualization and numerical simulation. In the experiment, the water condensation process inside the cathode GDL of a PEFC was observed by using water sensitive paper (WSP) and an optical microscope, and the water distribution under the current-collecting ribs and gas channels of the cathode separator was investigated. It was found that the water vapor concentration under the ribs increases immediately after the startup, and the water condensation occurs remarkably. In the simulation, the water distribution in the cathode GDL was predicted by a two-phase flow model, and validated by comparing the calculation data with the visualization results. The simulation results agreed qualitatively with the experimental results.

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The development of high-power-density Polymer Electrolyte Membrane (PEM) fuel cells is an effective approach to widely varied commercial applications. A bipolar plate is an important component for achieving high-power-density PEM fuel cells. Our investigation focused on a novel flow distribution method for the reactant gas in order to operate at a higher current density. Two types of bipolar plates with porous flow fields were evaluated. The hybrid flow field that consists of a porous medium and stamped land structure is superior in performance to the flow field made only of a porous medium. It is considered that the reactant gas distribution was improved by the stamped land region and increased the effective working area.

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In this research, the authors examine n-dodecane as a heavy-hydrocarbons fuel, which is a main constituent of kerosene. Then, the authors develop a small and simple steam-reforming reactor in a home-use size, for a fundamental study. The authors measure the hydrogen-molecule ratio R_<H2> together with the molecule ratios R_<CO>, R_<CO2> and R_<CH4> of other main gass components such as CO,CO_2 and CH_4 using a gas chromatograph, respectively. In addition, the authors conduct numerical simulations based on the thermal-equilibrium theory, and reveal R_<H2>, R_<CO>, R_<CO2> and R_<CH4>, as well as experiments. As a result, the authors successfully achieve suitable inside-temperature profiles, by the control of a thermal diffuser. The effects of the steam-to-carbon ratio S/C upon R_<H2> R_<CO>, R_<CO2> and R_<CH4> are shown, experimentally and theoretically. The experimental results agree with the theoretical ones qualitatively, but not quantitatively especially for R_<H2> and R_<CH4>.

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To solving the problems of conventional steam reforming of methane process, a novel two-step steam reforming of methane thermochemical cycle is proposed for pure hydrogen production. The whole cyclic process is divided into two steps. The first step is methane partial oxidation with lattice oxygen in metal oxide to form syngas and reduced metal oxide. The second step is metal oxide and hydrogen production from water splitting with reduced metal oxide, and metal oxide from this step is recycled to the first step and cyclic used. Principle and thermodynamics of this new cycle was introduced, different reaction systems was discussed. Coupled with solar energy, it is prospective to get a clean and economical way for hydrogen production.

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In the present study, we reveal the dominant chemical reactions and the optimum conditions, supposing the design of ethanol steam-reforming reactors. Experiments are conducted for Cu/ZnO/Al_2O_3 catalyst. Using a household-use-scale reactor with well-controlled temperature distributions, we compare experimental results with chemical-equilibrium theories. As a result, the Cu/ZnO/Al_2O_3 catalyst shows rather high performance at low values of reaction temperature T. This suggests that the Cu/ZnO/Al_2O_3 catalyst promotes the ethanol-steam-reforming and water-gas-shift reactions, but does not promote the methanation reaction. Furthermore, we specify the effect of steam-carbon molar ratio S/C upon concentrations such as C_<H2>, C_<CO2>, C_<CO> and C_<CH4>, together with the effect of T upon C_<H2>, C_<CO2>, C_<CO> and C_<CH4>. In addition, we have researched the influence of liquid-hourly space velocity LHSV upon the ethanol conversion X_<C2HSOH> at in the range of LHSV from 0.05 to 1.40h^<-1>, at S/C = 3.0 and T= 420K, 470K and 520K.

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From the standpoint of the environmental load, it is important to develop the hydrogen production system from methane produced by the fermentation of biomass such as food waste or wood waste. Compared with conventional catalysts such as pellet or Raschig ring type catalysts, monolithic catalyst is consider to be suitable for this process, especially for small-scale applications because it has the advantages such as high geometric surface area and the low pressure drop. We applied monolithic catalyst to autothermal reforming (ATR) of biogas. We examined at the biogasification bench-scale plant in Kyoto to obtain the optimum ratios of Steam/CH_4 (S/C) and O_2/CH_4 (O_2/C). As a result, it was found that the highest hydrogen concentration was attained at O_2/C=0.5 and S/C of 1.5-2.5. Moreover, we confirmed that the consistent performance was obtained under suitable conditions for the feed amount of steam and oxygen for over 800 hours.

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