We developed a thermal conductivity measurement system using a high-stiffness linear-motion guide and measured Li-ion battery electrodes which sealed within aluminum-laminated films. The apparent thermal conductivity of the battery electrode, which was measured at a temperature from minus several degrees to approximately 60°C, was from 1.1 to 1.4 W/(m･K) in the cross-plane direction, and from 37 to 38 W/(m･K) in the in-plane direction.

Thermal transport properties of silicone polymers containing thermally conductive fillers have been investigated experimentally and analytically. Composite sheets were fabricated by mixing silicone polymer with alumina particles with mean diameter of around 500μm. Temperature distribution observation were carried out with the composite sheets using a thermo-microscope and the effect of heating condition (continuous and pulse heating) on the temperature distribution in the composite sheets was discussed. Additionally, the steady and transient state thermal problems for the random unit cell model of the composite sheet were solved using ANSYS finite element program and temperature distributions in the composite were evaluated.

Recently, infrared thermographs are used frequently by electronic engineers in the design phase of electronic equipment. However, concerning the temperature measurement of a small-sized electronic component, the relation between the minimum area detectable of the peak temperature of an object and the area corresponding to one pixel of the detector of an infrared thermograph has not been known well. Therefore, in such cases, there is a possibility that a large error would occur. In this study, a simple method for estimating the peak temperature detection capability of the infrared thermograph has been proposed and discussed.

Three dimensional numerical analysis is utilized for thermal design of electronic devices. In this calculation, heat productions of electronic component are needed for input values, and they have an important consequence for prediction accuracy. But, it is often the case that the values are imprecision, because it is not well defined to measure or calculate the values at the moment. We developed a measurement method that is used a heatsink with cooling fan and a heat flow sensor. A heat production for a top of the electronic component is measured by the heat flow sensor. Total heat productions are calculated according to a correction algorithm. This measurement is executed in the state that electronic circuit is operated.

The purpose of this study is to maintain the performance of LiB (lithium-ion battery) of electric vehicle by controlling temperature of LiB. We verified the effectiveness of cooling system utilizing PCM (phase change material) and HP (heat pipe) at the time of sharp temperature rise of LiB as in abnormal heat emission. As a result, we found that cooling by PCM was more effective than cooling by HP at the time of sharp temperature rise of LiB.

Heat-transfer performance of the heat pipe is determined by dynamic wetting on the wall. In this study, an MD simulation of water droplet spreading on kaolinite wall: a material with both hydrophobic and hydrophilic surfaces, was conducted. We compared kinematic properties of water molecules near the contact line region when droplet is placed over the hydrophobic surface and the hydrophilic surface. As a result, different mechanisms of water molecules approaching the contact line region in the two cases were observed. The interaction between water molecule and wall was also analyzed in both cases.

Heat transfer characteristics of boiling part under low-pressure is examined experimentally in order to improve thermal performance of loop thermosyphon. Thermal performance of pyramid 2.5mm type is the best among test surfaces when pure water is used as working fluid. By adding surfactant to pure water, thermal performance is futher improved. However, the effect of surface type and surfactant on thermal performance is almost disappear at lowest pressure of 5kPa.

Porous metal fin was used as boiling heat transfer plate of phase change devices. The number of cells of the porous metal fin is 8 ppi, and the pore diameter of the porous metal fin is 3.1 mm. On the boiling heat transfer surfaces, the porous metal fin and the bass plate are brazed. Three samples of boiling heat transfer plates with the porous metal fin were made as prototype. Working fluids are HFE7000 and HFE7100 made by 3M. Predicting method of the boiling heat transfer coefficient was based on the expansion ratio of effective area to the flat plate and the correlation of that of Stephan's equation. The boiling heat transfer coefficient in the heat transfer plate with surface roughing process of concave can be put in order by ± 10 %.

A next-generation electric vehicle requires a high-performance IC inverter with the thermal emission of more than 500 W/cm² . To remove such a high heat emission, boiling heat transfer with microbubble emission boiling (MEB) is expected to be an advanced cooling technology because MEB can improve the maximum heat flux. On the other hand, the wall super heat in MEB is higher than that in CHF. In this study, we investigated the characteristics of MEB with and without a hydrophobic coating. As a result, the wall super heat with the hydrophobic coating in MEB was lower than that without the coating.

This paper describes comparison of temperature distribution between Si and 4H-SiC power MOSFET (Metal–Oxide-Semiconductor Field-Effect Transistor). In this paper, Electro-Thermal Analysis was employed for calculation of Si and 4H-SiC power MOSFET. Recently, SiC device has attracted attention as high power and high temperature power device. However, thermal properties of SiC power MOSFET are not clear. Therefore, in this study, hot spot temperature and average temperature of Si and SiC power MOSFET under various drain voltages are compared. From this result, the thermal properties are not same, and hot spot temperature of 4H-SiC power MOSFET is lower than Si power MOSFET in the case that both power MOSFETs have same structure.

SiC is expected as a next generation power semiconductor material due to its excellent properties. For SiC power device production, an efficient drilling method for 3D packaging technology aiming at further space saving is needed. In order to improve the quality of laser drilling process on SiC, Bessel beam laser drilling was conducted. Due to side lobes of Bessel beam, the effects of its long focal depth and small spot size were not obtained under the processing parameters we selected. To find appropriate processing conditions of Bessel beam laser drilling, further investigation is needed.

Thermal triple-axis accelerometer based on micro-electromechanical systems (MEMS) has a cavity enclosed by an outer wall, thermal detectors and a ring-shaped heater wire in it. The heater warms up the air inside the cavity and generates laminar convection. The heated air moves in the direction of the acceleration because of buoyancy effect. The thermal detectors detect the deviation of temperature caused by the warm moving air. There is a proportional relationship between the change in temperature and the magnitude of acceleration, and hence the accelerometer can detect the direction and magnitude of the acceleration from the temperature change. When the acceleration changes at a certain frequency, it can be calculated from frequency characteristics.

This study describes a possibility of an improvement of fans' cooling technique while decreasing time-averaged power consumption of a fan mounted in electronic equipment. The cooling performance of the square prism object by the axial small fan was evaluated while changing the input voltage to the fan periodically. Through the experiment, it is found that the fan's cooling performance can be maintained while decreasing the time-averaged power consumption according to the pattern of the intermittent operation of the fan. The possibility of the energy saving of the fan cooling can be confirmed.

This study describes a possibility of heat transfer enhancement in mm-scale water-cooled channels using pulsating flow. The effect of heat transfer enhancement around cylindrical or square prism obstructions by using pulsating airflow have been clarified. Our study is trying to apply pulsating flow to heat transfer enhancement method in water-cooled device. In this report, we especially investigated the effects of the combination of the rib and the pulsating water flow on the heat transfer performance in the square mini channel through CFD analysis. It is found that the heat transfer performance in the water cooling channel can be enhanced by using the combination of the rib and the flow pulsation.

In order to let power electronics apparatus extend its life, it is necessary to keep the temperature of the apparatus constantly by some kind of cooling methods. Though the forced air-cooling by the fresh air introduction is the most efficient of all cooling methods, cooling performance decreases because dust included in the fresh air invade the apparatus and attach to the apparatus. Therefore, in this article, we report the result the best structure optimized by the simulation and the performance evaluation with the trial product.

This study describes a possibility of an improvement of cooling performance on the surface of heating elements by using an intermittent jet flow like a geyser in nature. In this report, we tried to evaluate the heat transfer performance of the intermittent impingement jet on heating surface, which simulates the surface of the cooling channel or the electrical chips. We developed the flow tunnel which can generate the intermittent jet on the heating surface and the heat transfer experiment was performed. Through the experiment, it was found that the intermittent impingement jet has almost the same heat transfer performance as the steady impingement jet regardless of the decrease of the time-averaged supply flow rate.

This paper describes fundamental heat transfer performance of porous metal sheet under natural convection condition. In recent years, passive cooling techniques are required even in high heat generating electrical device because of miniaturizing of equipment and not enough space for cooling. Porous material sometime acts as thermal insulator due to its high dense air contents. However, if the material is metal and has high porosity, it is possible to behave as a heat sink. In this study, several types of porous metal was prepared and fundamental cooling performance as a heat sink was evaluated.

Toward the improvement of performance of the air-cooled generator, an appropriate design for the heat removal is important. The present study numerically clarifies the flow behavior and heat transfer characteristics in rotating coaxial cylinders simulated a salient-pole rotor within the air-cooled generator. The same vortex structure as flow visualization was identified. Heat transfer coefficient on the trailing side wall near separated flow was lower than that on the leading side wall. It is implied that temperature on the wall near separated flow increased because of flow congestion at separated flow region.

In order to examine the generation mechanism of the vertebrates, including humans, and to explore the diverging point of the genetic abnormalities, it is effective to investigate the growth of the embryo of an artificial mutant. As the embryos of Medaka or Zebrafish hatch outside of the body and their egg membrane are transparent, it is quite easy to carry out the in-vivo observation of their organs. Moreover, the development and the structure of their major organs are quite similar to those of human. Thus, the observation of the developmental abnormalities of Medaka embryos may serve as a clue to the pathologic investigaion of the genetic disease and hopefully give some insight to the effective treatment. Presently, the venous and intracardiac blood flows of Medaka embryos have been observed by a high-speed camera under microscope. The obtained images are processed and the velocity fields in the main vein and the heart are measured by PIV.

We have proposed a simple method for measuring thermal conductivity of gases and liquids using a micro-beam MEMS sensor that is a ~10-μm long free-standing membrane suspended across a trench on a silicon substrate. In this study, we fabricated a device that has a mini-channel to supply a liquid to the sensor. Using this device, the thermal conductivity of FC-72 and ethanol was successfully measured with samples of only 30 μL.

This study describes the measurement of CO₂+N₂ mixture flow concentration using CARS (Coherent anti-Stokes Raman Scattering). CARS is generated by two excitation beams of different wavelength, which excite the vibrational motion of the molecule. This method can selectivity measure the molecule of gas, which means that the non-intrusive measurement is achieved. However, the non-resonant background noise has been generated from channel walls. The objective of this study is to reduce the influence of the background noise by varying diameter of excitation beam in order to energy densities of excitation beams transmitted through the channel walls.

A non-intrusive, two-dimensional temperature measurement technique in electrolyte solution was developed by spontaneous Raman imaging. Raman scattering from water molecules was focused on for the temperature measurement, and the temperature was measured by using a calibration curve depicting the correlation between the Raman intensity and temperature. The temperature-sensitive NHB band, which appears due to OH stretching vibration of water molecules, and ν₂ band, which appears due to vending vibration of H₂O, were simultaneously detected by a two-wavelength Raman imaging system which consists of two cameras and two optical filters. By using these two different Raman bands, a spatial distributions measurement of temperature in electrolyte solution was achieved.

The purpose of this study is to establish a measurement method of gold nanoparticles zeta potential using builtin device called Evachip. Evanescent wave generated using an Evachip are capable of illuminating the vicinity of an interface easily. The conventional measurement methods of nanoparticle zeta-potentials had complicated optical systems and cost a lot. Therefore a simpler measurement method was desired. Gold nanoparticles zeta potential was estimated from electrophoresis velocities using the formulas of Helmholtz-Smoluchowski. This measurement method using evanescent enabled nanoparticle zeta-potential measurement in the vicinity of the liquid-solid interface.

This paper shows heat generation rates of a 1-mm-diameter magnetic sphere at different positions in a magnetic field. To determine the heat generation rates, temperature distributions of water around the sphere were measured by the near-infrared absorbance imaging method based on the temperature dependence of absorbance of water at the wavelength of 1150 nm. A two-dimensional map of the heat generation rates, corresponding to the distribution of magnetic field intensity, was constructed. These values of heat generation rates agreed with theoretically estimated values.

Superheated steam/high-humidity air over boiling point temperature is used as a heating media for food heating machineries, such as steamers and ovens. However, there is no suitable humidity measuring equipment under high temperature and humidity air. Therefore, we have developed a measuring device using porous ceramics based on the principle of the psychrometer. In this study, we have developed a humidity generator of calibrate the humidity measuring device. Standard humidity is generated by mixing of hot air and superheated steam. We have verified the accuracy by comparing values in steam mole fraction measured by the calibrated dew-point instrument and by the flow meters as well as by the psycrometer using porous ceramics. We have analyzed uncertainty of the generated humidity to evaluate the reliability.

Effects of temperature gradient on ultrasound velocity profile method was evaluated by experiment. Ultrasound echo signals under temperature gradients condition was measured. The incident ultrasound beam which was caused by temperature gradients. After the confirmation of refraction beam, flow caused by heater was measured by an ultrasound phased array 2-D velocity profile measurement system. An upward flow was observed as expected using this system. As a result, the availability of flow measurement by phased array system under the temperature gradient environment was confirmed.

The purpose of this study is a development of the local thermal conductivity measurement method by contact temperature method. In this paper, the applicable conditions of this method were examined. First, by the numerical simulation of heat conduction and the measurement test for non-conductive materials coated with gold film, it was found that the proposed method with the platinum wire probe is useful for thermal conductivity of 1 to 100 W/mK. Spatial resolution of this system was also examined. It was noted the resolution for low conductivity sample is approximately 100 μm.

The heat transfer of natural convection from the horizontal heated surface which a heated annular duct was placed above was investigated experimentally. The relationship of the flow and heat transfer characteristics to the height and the heat flux of the heated ducts were examined. With decreasing the height, the induced flow rate decreases and the reverse flow occurs. The heat transfer increases with increasing the modified Rayleigh number of the heated ducts. However, when flow reversal reaches to the horizontal heater, the heat transfer has a little influence on that.

Natural convection cooling is used for medium or small capacity motors with low revolving speed. In order to raise the cooling performance in natural convection, the fin which consisted of laminated iron core, and the cast frame fin are applied. Cooling performance is determined by heat conduction anisotropy of a laminated iron core, contact thermal resistance between iron core and the frame, and fin pitch, etc. This paper describes the evaluation of a fin pitch which is suitable to natural convection by using computational fluid dynamics, and the results using the thermal network to decide presence of a frame.

This study describes a heat transfer characteristic on the heating rotating horizontal disk in the opened space. The heat transfer on the heating rotating disk becomes mixed convection which is affected by both buoyancy and centrifugal force. In this study, a relationship between the rotating Reynolds number and the heat transfer characteristics on the disk was investigated through three-dimensional numerical analysis. The transient change of the heat transfer was also observed. When the rotation speed becomes slower and buoyancy force becomes stronger, natural convection heat transfer becomes dominant. On the other hand, when the rotation speed becomes faster and centrifugal force becomes stronger, forced convection heat transfer becomes dominant. In these cases, we can predict the heat transfer characteristic by using the conventional formulas. However, when buoyancy force balanced with centrifugal force, the different heat transfer characteristic from both natural and forced convection conditions can be observed.

Thermocapillary flow in a liquid bridge changes from laminar to oscillatory flow with increasing a temperature difference at the free surface. It is considered that the heat transfer at the liquid bridge surface is one of the important parameter to determine the onset of oscillatory flow. The effect of Biot number on the critical Marangoni number was investigated by changing a thermal conductivity of the ambient gas experimentally. The critical Marangoni number was remarkably different from not only the Biot number but also the thermal conductivity of the gas. It was assumed that the transition of oscillatory flow is not organized by the average Biot number and should be considered the local heat transfer at the surface.

Ionomer structural properties in a mixture of 1-propanol (NPA) and water have been investigated using coarse-grained molecular dynamics simulations. To perform simulations of larger systems and longer time spans, the reduced spatial resolution of the bead representation was used as a coarse-grained model for the enhancement of the computational efficiency compared to all atomistic simulations. The dependence of NPA content on the ionomer structures was studied by systematically changing the NPA content in the system. The self-assembly behavior of Nafion ionomers into cylindrical bundle-like aggregates was observed for all NPA content solutions. The ionomer aggregation size was found to tend to be larger and thus more dispersive at higher NPA contents, although the ionomers aggregated into one cluster at all NPA contents.

Polymer electrolyte fuel cell (PEFC) performance highly depends on proton conduction and oxygen transport in Catalyst layer (CL). Ionomer is one of the most important ingredients in CL of PEFC. Therefore, we need to develop a novel method to investigate ionomer distribution in CL. In this paper, we proposed a two-stage ion-beam processing method combined with ion milling and FIB processing for preferentially removing ionomer in CL. Applying this technique to the CL, we succeeded in visualization of ionomer distribution in CL.

The high-frequency resistance of catalyst inks under the drying process to fabricate catalyst layer for polymer electrolyte fuel cells was measured by using a microelectrode chip. The catalyst inks with the different ionomer to carbon (I/C) ratio were measured. Surface observation by using a digital microscope was also conducted at the same time. The catalyst ink with I/C 0.6 showed larger resistance at the beginning of the drying than that with I/C 0.8 because proton concentration in the ink is low. I/C 0.6 also showed drastic resistance drop. This result indicates that I/C ratio affect the stability of the catalyst ink.

Improvement in power generation performance of Polymer Electrolyte Fuel Cell (PEFC) is required for its market supremacy. The microstructure of cathode catalyst layer (CCL) is known to dictates the power generation performance of PEFC. Also, the requirement for the species transport characteristics should vary with the thickness-wise position in CCL. In this report, we fabricated three kinds of multi-layered CCL that has the difference in I/C ratio of 2nd layer, and investigated oxygen transport-reaction phenomena by evaluation polarization characteristics, electrochemical surface area and oxygen transport resistance in the CCLs using limiting current measurements. As these results, it was found that there is an optimization strategy of I/C ratio in 2nd CCL.

Insufficient supply of oxygen (O₂) to the cathode Pt catalyst layer can be caused by transport resistance, and is a major problem in proton exchange membrane fuel cells. To clarify O₂ transport phenomena, a non-destructive technique for measuring the O₂ concentration is required. In this study, the O₂ concentration at the catalyst layer was measured under operating conditions, using a tiny optical fiber and oxygen indicator. The O₂ concentration decreased continuously with decreasing cell voltage. It was considered that a decrease in size of the reaction area was caused by water accumulation and vapor generation. Local O₂ concentration measurements suggested that power generation was concentrated at the limited region.

One of the problems in Polymer Electrolyte Fuel Cell (PEFC) is degradation of membrane by hydrogen peroxide produced by reaction of crossover hydrogen and oxygen in membrane phase. Knowing properties of the degradation leads to durable design of PEFC. We evaluated the transport properties of the crossover gas species by using limiting current measurements by platinum microprobes. The parameters of gas flow rate, temperature, relative humidity (RH) and channel length were changed to investigate the impacts of the conditions on the transport properties along gas channel direction. Also, the distributions of water content in membrane were calculated to analyze the influence on the transport properties.

Performance evaluation of a monolayer electrode polymer electrolyte fuel cell, which consists of a polymer electrolyte membrane, catalyst layers, and separators with a narrow channel, was conducted. Two cells were fabricated. A cell has large facing area, where the narrow channel faces on the counter channel, while the other cell has the small area. The cell with the large facing area showed higher performance. The polarization curve corrected by the facing area was almost consistent with that of the other cell. Therefore, it is indicated that the facing area of the cells is the dominant area for the electrochemical reaction.

We have developed a Membrane Electrode Assembly (MEA) with a water management catalyst layer for Polymer Electrolyte Fuel Cells (PEFCs) by adding the carbon powder (NBH) with a water absorption performance to water management catalyst layer. The NBH with a Nano-pore was made by carbonizing the rice husk, and it functioned as an activated carbon. Although the water generated by cell reaction is absorbed to the Nano-pore of NBH, the absorbed water is not emitted outside from the catalytic layer by strong capillary force. However, the absorbed water is supplied to the membrane by a concentration diffusion of water under non-humidity condition. As a result, the MEA with NBH without humidifying obtained a good cell performance compared to the standard MEA even though the amount of platinum catalyst is reduced.

Water management is very important in the development of the PEFC. The purpose of this paper is to present a new method for utilizing the generated water to humidify the polymer membrane actively. We have developed a humidity control porous rib system. By changing gas flow direction in cathode side, the porous rib changes its function of both moisture absorption and dehumidification, according to the local humidity condition. In this study, experimental and numerical examinations were carried out to understand the effect of the humidity control porous rib on the water behavior and the cell performance of the PEFC. It is confirmed that the humidity control porous rib system can control water behavior and improve the cell performance.

In order to obtain an oxide ion concentration profile in solid oxide fuel cell (SOFC) anode, a quenching system of a SOFC single cell has been developed. A SOFC power generation equipment with a nozzle for helium impinging jet, which is covered by a water cooling jacket, was prepared. The quench experiment shows that the temperature of YSZ electrolyte could be decreased from 830 to 150 °C within 1.5 sec, which was in good agreement with analytical results based on the average Nusselt number of impinging jet heat transfer. In addition, a diffusion distance of an oxide ion in YSZ bulk during quenching process was calculated based on the obtained temperature profile with respect to time and a diffusion equation.

In this study, carbon deposition on Ni/YSZ anode exposed to dry methane was investigated. Thorough off gas measurement and elemental analysis of component of anode after exposure to dry methane, it was suggested that carbon, first, deposits on the surface of nickel selectively, and then, deposits on the deposited carbon. In addition, it was found that anode layer expanded after exposure to dry methane, which can cause destruction of anode structure.

In-plane temperature distribution of gas separator at anode and cathode of single cell of PEFC generated at high temperature was measured by thermograph. The effects of initial operation temperature of cell, relative humidity and flow rate of supply gas as well as cathode gas type on the in-plane temperature distribution were investigated. As a result, the temperature increased along gas flow through gas channel from the inlet to the middle, and then decreased. The impact of relative humidity difference of supply gas between the anode and the cathode on the temperature distribution was not confirmed under the investigated conditions.

The polymer electrolyte fuel cell is one of the energy supply system for aerospace application. In aerospace, the pressure around the fuel cell becomes lower than atmospheric pressure (vacuum environment), and the heat control of PEFC becomes more critical issue. To control the cell temperature, we embedded water cooling in fuel cell system, and analyzed the cell temperature under the atmospheric and vacuum environment. Results suggested that adequate flow rate of the water cooling can control the cell temperature even under vacuum condition and improve performance of the cell. Furthermore, right waight based on simplification is imposed in aerospace application. Recovering the produced water from cell and regenerating hydrogen and oxygen gas from the water are also required. Operating PEFC without humidifier and with re-circulation of supplied gas aiming for the recovering are responsible for these specific needs. Experiment clarified that operation without humidifier operation can work in the same performance as that with humidifier under room temperature. It also found that operation with the re-circulation does not degrade the performance once flow rate of the recirculation is controlled to be enough high so that gas velocity in channel is high and reduce concentration overvoltage.

Recently, although PEFC begins to commercialize in various fields such as domestic co-generation system and fuel cell vehicle etc., it is necessary to reduce the cost compared with an existing competitive commodity for a further dissemination. One of the costly parts is the carbon separator which demands a high airtightness, a high drainage and a high durability. The current specification of the carbon separator is not optimized by system requirements of each fuel cell commodity though the environment for which the fuel cell is used by each commodity is different. Therefore, we evaluated the influence of each carbon material characteristic on the cell performance by installing each separator made of each carbon material to the PEFC single cell. As a result, although the influence of each carbon material characteristic on the cell performance was able to be confirmed, we were not interpretable whether which material property influences the cell performance.

Our proposal diagnostics evaluates the PEFC's transient response with a resistance polarization, an activation polarization and a diffusion polarization, and derives diagnostics parameters by analyzing this transient response. As we have already established this diagnostics system for the 25cm² PEFC single cell, we tried to elucidate the degradation factor distribution in the same electrode by applying it to the quadrisection separator. As a result, our diagnostics was able to judge the difference of the degradation factor in each section in the same electrode. Especially, the diffusion polarization depends on the current density distribution because the integrated quantity of the generated water controls the presence of the flooding generation. Moreover, because the resistance polarization at the cell center front is the highest under any condition, we have to confirm whether this tendency is a specific behavior of the cell center front.

Due to the growing demand for high efficiency power generation system, solid oxide fuel cell (SOFC) is one of the candidate systems because of its high efficiency and fuel flexibility. In order to improve efficiency and reliability of the electrodes, introduction of fin structures in the electrodes are effective. However, fabrication of fin structures on SOFC electrode is challenging, because electrodes are made of hard brittle ceramics which are difficult to manufacture. To solve this issue, a combined process of powder metallurgy and micro molding is developed. The developed combined process enables flexible patterning of hard brittle ceramics material. In addition, micro scale molds can be copied easily, which is suitable for mass-production.

Ni-YSZ anodes of solid oxide fuel cells are fabricated using the infiltration method to control their microstructure. Microstructure of the anode with the infiltration method is evaluated by using focused ion beam scanning electron microscope and compared with that of an anode fabricated with the conventional method. From the electrochemical impedance measurement, the infiltrated anode is found to have much less polarization resistance than the conventional anode. Moreover, the infiltrated anode has sufficient Ni connectivity, smaller Ni particle size and higher triple-phase boundary (TPB) density. On the other hand, the infiltrated anode has larger ohmic resistance due to contact resistance between a current collector and surface of the anode.

Ammonia can be used as a fuel for solid oxide fuel cell (SOFC) systems because anodes of SOFCs generally contain nickel, which works as a catalyst of ammonia decomposition. This research aims to observe the phenomena on Ni-YSZ anode surface during the ammonia decomposition. First, temperature distribution on the anode surface is obtained by using an infrared camera. Temperature drop is observed near the upstream edge of the catalyst when ammonia is supplied to the catalyst. Numerical simulation was also performed to obtain information which can't be observed through the experiment.

The authors develop a small and simple steam-reforming reactor in a home-use size for such various heavy-hydrocarbons fuels as n-octane, n-decane, n-tetradecane and n-hexadecane in addition to n-dodecane. Under the thermal condition controlled by electric heaters and a gas burner with a thermal diffuser, the authors measure the inside-temperature profile and the hydrogen molar fraction (concentration) C_H2, together with the molar fractions C_CH4, C_CO and C_CO2 of other main gas components such as CH4₂ , CO and CO₂ , respectively. As a result, the authors successfully achieve suitable inside-temperature profiles. And, the authors reveal the effects of the liquid-hourly space velocity LHSV upon the molar fractions, a conversion ratio X_C12H26 and reforming efficiencies for various heavy-hydrocarbons, which suggest the common upper limit of LHSV for the practically-suitable operation.