Recent stationary battery containers have cuboid battery modules with a forced air convection cooling system. A resin case of battery module is molded with a lot of ribs. The flow around battery module is modeled as a cuboid with textured surfaces by ribs in a narrow rectangular duct. Previous similar researches for cuboid with a rectangular duct are assumed for wide gaps between cuboid and duct walls. To design the forced air convection cooling system, heat transfer coefficients around a battery module and flow have to be evaluated. The paper proposes a flow visualization method to investigate flow around a cuboid with textured surfaces in a narrow rectangular duct utilized in a digital camera for consumer use and high intensity slit LED (Light Emitting Device.)

In this research, nanoparticle-layer was used as the wick in a cylindrical heat pipe to experimentally investigate its effect to enhance the heat transfer performance. In the experiment, the one end of the heat pipe was heated using a nichrome wire heater and the other end was cooled using saturated boiling pure water. In addition, effects of pre-coating of the screen mesh and the inside wall of the heat pipe with nanoparticles on heat transfer performance were explored. The experimental results showed that in comparison with the normal heat pipe BBW (bare tube / bare mesh / pure water), the thermal resistances of BNW (bare tube / nanoparticle-coated mesh / pure water) decreased 16-73% if the deposited amount of nanoparticles were sufficient. The critical heat flux (CHF) increased 1.7 times and the performance was not deteriorated even after the CHF condition was experienced. If the weight of deposited nanoparticles was sufficient, the thermal resistances of NXW (nanoparticle-coated tube / no mesh / pure water) decreased 16-71% although CHF dropped about 30%. Performance degraded after the CHF condition was experienced．When the working fluid was changed to a nanofluid, the thermal resistances of NXN (nanoparticle-coated tube / no mesh / nanofluid) decreased 14-74% and the CHF increased 1.6 times. Performance was not deteriorated even after the CHF condition was reached. Since the nanoparticle layer is thin, it may effectively be applied particularly to small heat pipes for small electronic devices.

This study proposes a new method for producing silicon crystal substrates utilizing surface tension and electromagnetic pressure. In our previous model experiments with a special alloy under the condition that an alternating current of 361 kHz was applied, producing substrate failed due to overcooling. It was considered that production of substrates can be expected by increasing heat generation. In this study, heat generation and electromagnetic pressure when frequency was increased to 407 kHz were calculated with magnetic field analysis software. In addition, the optimum velocity of cooling wind for the heat generation was calculated with thermo-fluid analysis software and applied to the producing substrate process.

Visual observations of bubbles and wall temperature were carried out to explore the mechanisms to cause departure from nucleate boiling (DNB) in subcooled flow boiling. It was observed that as presumed in the liquid sublayer dryout model, DNB was incepted when the liquid film between the wall and the large bubble was exhausted. At high flow rate and high subcooling condition, however, DNB was triggered immediately after the formation of large bubbles. The situation at DNB in this case would hence be similar to that supposed in the near-wall bubble crowding model since the bubble crowding leads to the formation of large bubbles.

With the increasing performance and miniaturization of electronic devices, the use of high-power components and the high density of component mounting are being promoted. When the heat generation density becomes high and the temperature of the mounted component rises, it leads to component failure or instability. Therefore, it is necessary to efficiently dissipate the heat generated by the component. On the other hand, in order to ensure the mounting reliability of the component, it is necessary to reduce the difference in thermal expansion between the component and the PCB(Printed circuit bord), and it is necessary to ensure heat dissipation and at the same time reduce the thermal expansion of the PCB. Therefore, we have developed a new multi-layer PCB that uses Cu-Mo composite materials and has both high heat dissipation and low thermal expansion.

According to the NEDO roadmap, the operation temperature over 90 ℃ and 100 ℃ is the target of PEFC systems for stationary and vehicle application respectively from 2020 to 2030. Numerical analysis using COMSOL Multi-physics was performed to clarify the mechanism and dominant factor of various coupled phenomena in a single cell of PFFC under high temperature operation condition. The relative humidity of inflow gas was also changed. As a result, it was found that the amount of produced H2O as well as current density decreased with increase in operating temperature irrespective of relative humidity condition.

Many correlations have been developed so far for the bubble departure frequency in forced convective subcooled boiling, but their prediction capability is still not satisfactory and further improvement is required. In this study, bubble behavior and wall temperature transient were visually observed using a high-speed camera and an infrared camera, respectively, to measure the bubble departure frequency and bubble diameter at each active nucleation site individually. It was found that nucleation is interfered by the wall temperature reduction caused by the bubble formation at nearby nucleation site. This indicates that the effect of interference from nearby nucleation sites should be included for accurate prediction of the bubble departure frequency.

An experiment was conducted to clarify the local heat transfer fluctuations in the boiling heat transfer of a falling droplet. In this report, a droplet was dropped on a heat transfer surface, and the boiling behavior was photographed by two high-speed cameras, one from diagonally above and the other through the heat transfer surface. At the same time, the heat transfer fluctuations were measured with an infrared camera. As a result, it was possible to measure the series of the process of formation, growth, and collapse of the boiling bubble with the corresponding fluctuations in heat flux distribution quantitatively.

The melting of opposite horizontal ice plates into binary aqueous solution is considered experimentally. Specifically, mean melting mass of ice plates, flow field in the liquid layer and temperature decrease of ice plates are examined in this paper. At the beginning, flow field is chaotic. Melted water stagnated in the upper part of the aqueous solution layer, and the melting of the upper ice plate was gradually suppressed. Therefore, it is considered that the melting from above is the main cause of the vertically opposite melting. As the melting progresses, the melting system is suppressed as a whole, and the velocity field gradually weakend.

Effects of orientation direction, Darcy number and Rayleigh number of the porous metal fins installed in a rectangular enclosure on the solidification process are investigated by dimensionless numerical analysis. Specifically, the thermal storage capacity in PCM and the time to complete solidification are examined in this paper. Comparing the three cases of porous metal fins, full porous, and only PCM, we confirmed that porous metal fins have an advantage in thermal storage. Especially in the early stage of solidification with porous metal fins, cold heat is used for sensible heat rather than latent heat because of convective flow.

For thermal design, it is necessary to know the thermal properties such as thermal conductivity with high accuracy. We have developed an apparatus based on ASTM E1530 and D5470, but it is necessary to measure samples of the same material with different thicknesses in order to measure the thermal conductivity considering the thermal contact resistance. In this study, we investigated a method to measure the thermal conductivity considering the thermal contact resistance from a single sample. The measurement results of the conventional method and the proposed method were compared in a measurement system with an infrared thermography camera added to the measurement system of the conventional method.

Air cooling technology is widely used for cooling electronic devices, air conditioning devices, and engines. In order to realize a highly information-oriented society in the near future, thermal management of many related electronic devices requires a new cooling technology that exhibits excellent cooling performance with much lower power consumption. In this study, we evaluate heat transfer performance of a new air-cooling technology with lotus copper wavy fins that introduces "breathing effect". The lotus fin has unidirectional pore structure that induces gas flow passing between the fins, which enhances the heat transfer performance.

In a bipropellant thruster, a part of the liquid fuel is injected onto the combustion chamber wall to form a liquid film, which protect the wall from combustion gases. Particularly in the pulse operation, the fuel is injected onto a heated wall with temperature gradient formed by heat soak back from the nozzle throat. In this study, the transient processes of film formation and wall temperature distribution were visualized using a high-speed camera and an infrared camera, respectively, for a liquid film formed by a pulsed injection of liquid jet on a heated wall surface with temperature gradient. As a result of the analysis, knowledge about the liquid film behavior during the cooling and no-cooling periods was obtained.

Carbon-free energy sources, such as hydrogen and ammonia, have recently been attracting attention as next-generation fuels. Ammonia has many advantages compared with hydrogen in terms of transportation, such as its ability to be liquefied at atmospheric temperature, but low burning velocity and the high NO_x emissions rate are major issues. If conventional burners for hydrocarbon fuel can be applied to ammonia combustion, it will be easy to switch between hydrocarbon combustion and ammonia combustion with the same burner. In this study, we experimentally investigated the possibility of realizing Low-NO_x ammonia combustion by using a hydrocarbon fuel burner with the two staged combustion method in which fuel and oxidizer are separately injected into the furnace.

We attempted to discriminate active-transport stop by measuring electrical impedance at the ambient temperature that seemed to be the boundary of active-transport stop in cold stored cells, and compared it with the survival rate after storage. Rat cardiac myocyte was stored at 4 to 7°C for 3 to 12 h, and the electric impedance was measured during storage. The results showed that the electric impedance of rat cardiac myocyte was significantly lower at 4°C and 5°C for 12 hours than at 3 hours, and the survival rate was also lower. It was suggested that influence of an active-transport stop on cell damage was great.

In nucleate pool boiling of nanofluid, a nanoparticle layer is formed on the heat transfer surface. Since the nanoparticle layer adheres to the heat transfer surface, the material of the heat transfer surface may have a noticeable effect on the pool boiling heat transfer performance. In this study, the effect of the heat transfer surface material on the boiling heat transfer was examined. In addition, the surface properties of the nanoparticle layer were measured to explore the difference in the surface properties caused by the heat transfer surface material.

We aim to propose a heat transfer promoter using uniporous structure fabricated by explosive welding technique toward its practical use. In this study, we evaluate the heat transfer performance of a double-tube heat exchanger in which the outer-tube channel has the uniporous structure and the inner tube is a circular tube. The heat is exchanged between hot water passing through in the inner tube and cold air flowing in the outer porous tube. The heat transfer quantity and the temperature efficiency per unit volume show higher performance than those of a commercial double tube heat exchanger with similar geometry.

As a technology of exhaust gas heat recovery, the thermoelectric generator using the loop thermosiphon (LT-TEG) has been developed. The loop thermosiphon can transport exhaust gas heat effectively to the thermoelectric modules. This study has considered installing two LT-TEGs along exhaust gas flow. It is concerned that decrease in the heat input on downstream side causes deviation in the electric output between the two LT-TEGs. To maximize the electric output of both the LT-TEGs, it is necessary to suppress the deviation. To do this, the refrigerant channels of the two LT-TEGs have been connected so that they can share the refrigerant of uniform pressure. Numerical modeling of the joint system and its experimental verification have been performed.

This paper reports the visualization of frost formation behavior at fins used in heat exchangers and the investigation of thermal properties of the frost layer surface using infrared thermography. Visualization uses two types of fins to understand the difference in frost formation behavior. In infrared thermography, the Nusselt number on the surface of the frost layer on a flat plate was calculated as a preliminary step to determine the heat transfer coefficient of the frost surface adhering to the fins.

Heat transfer performance of aluminum and copper surfaces with fine tunnel structures are investigated experimentally. We measured heat transfer performance of 7 new tunnel surfaces (No.1~3, No.6~9). Fluorine-based refrigerant HFE-7000 was used as a working fluid. Absolute pressures used are 0.10MPa,0.14MPa,0.18MPa, respectively. New surface No.1 surface has the highest heat transfer performance among tested aluminum surfaces. Heat transfer is higher than 11 times of smooth surface and 2 times of the reference tunnel surface No.4 at 80kW/m² of 0.14MPa. When the fin height is too high, the heat transfer performance is significantly decreased. When comparing the copper and aluminum surfaces, the heat transfer performance of copper is superior to aluminums.

We conducted the single droplet evaporation experiments for iso-octane/ethanol blended fuel to research the effect of adding ethanol on single droplet evaporation characteristics of iso-octane. To investigate the effect of blending ethanol, we compared experimental results of iso-octane/ethanol blended fuel and iso-octane/nonane blended fuel. From experimental results, we obtained three findings indicated below. First, molecular clusters may be formed in iso-octane/ethanol blended fuel, and molecular cluster may make intermolecular force stronger. Second, the droplet lifetime of 50wt% iso-octane + 50wt% ethanol blended fuel was almost the same as that of 25wt% iso-octane + 75wt% ethanol blended fuel and ethanol. Third, the instantaneous evaporation coefficient of 50wt% iso-octane + 50wt% ethanol blended fuel and that of 25wt% iso-octane + 75wt% ethanol blended fuel show almost constant like a single component droplet.

Ice slurry, which consists of water and fine ice has high fluidity and cooling efficiency, hence ice slurry is expected to be used for cold heat in various fields. However there is a problem that ice particles in ice slurry gradually cohere with passage of storage time. In this study, two types of silane coupling agents with different organic functional groups were added to the ice slurry, and the effect of silane coupling agent on the cohesion of ice slurry was investigated by measuring porosity, ice particle diameter, and cohesive force.

Flame synthesis can be performed by jetting an oxidizer flow with fine particles into the center of the six merged diffusion microflames under appropriate conditions. In this study, the gas composition distribution in flames was measured in order to clarify the suitable conditions for oxidation synthesis. As a result, it was found that even if the tip of the inner inverted diffusion flame was opened by increasing the oxidizer flow rate or the oxygen concentration, an oxidizing atmosphere containing oxygen did not necessarily reach up to the tip of the flame.

An all solid-state lithium metal battery has high theoretical energy density and is a candidate of a next generation secondary battery for electrical vehicles. However, high cycle performance has not been achieved owing to the lithium dendrite generating in charging process. In this study, cycle performance measurements of all solid-state lithium metal battery symmetric cell are conducted with changing the particle size and the molding pressure of separator made by sulfide and oxide solid electrolyte. The result show that, in the case with sulfide solid electrolyte, solid electrolyte particle size and molding pressure changes the durability of the separator. Relatively high durability is achieved with small size particle and optimum molding pressure. In the case with oxide solid electrolyte, the durability is increased with the decrease in particle size but is not dependent on the molding pressure.

Transient heat transfer of decaying swirl flow in a circular pipe was investigated by the technique using a high-speed infrared thermograph. The flow was swirled by a twisted tape upstream of the test section, and the heat transfer of the decaying swirl flow was measured using a test pipe composed by a heated thin foil. The Reynolds number was ranged between 1000 and 12000. It was confirmed that when the flow was swirled, heat transfer was enhanced at the same pump power in the Reynolds number range examined here. In particular, the enhancement was confirmed in the transition regime between laminar and turbulent (Re = 1600～3400), being about 40%.

The effect of the sample holding method on the flame spread phenomena of printed circuit boards was investigated. To realize the two-dimensional flame spread front over the printed circuit board, we provided the air gap between the side edge of the sample and sample holder wall. The air gap can reduce the heat loss from the sample to the holder, however edge propagation started to appear when the size of the air gap increased excessively. To find an optimal size of the air gap, flame front shape, flame spread rate, and limiting oxygen concentration were measured by changing the size of the air gap and those results are reported in the presetnation.

In order to comprehend fluid dynamics of gas-liquid two phase flow through plate heat exchangers flow of HFE7000 between inclined parallel plates has been numerically inverstigated based on a mixture model for gas-liquid two phase flow with the phase changes. The characteristics of the flow patterns for various flow configurations were discussed and both the Nusselt numbers and pressure drops were evaluated. As the results using plate heat exchangers, that the gas-liquid phase change could effectively enhance the heat transfer between the working fluid and the surfaces, and the prefered orientation for the installation of the plates could be identified based on the combination of the heat transfer coefficient and the pressure drop.

In this study, the heat transfer coefficients were measured to investigate the effects of surface shape for the heat transfer characteristics of impingement air cooling system. The surface shape applied to obtain the variation in the heat transfer coefficient was the pyramid-like-surface and smooth surface. As a results, the heat transfer coefficients of both the pyramid-like surface and smooth surface were increased with increasing the pressure ratio of air. Moreover, it was found that the application of pyramid-like-surface improved the heat transfer performance of impingement air cooling system by the change of pyramid angle.

Many studies have been conducted so far on droplet entrainment in annular two-phase flow, but knowledge on boiling entrainment phenomenon is still insufficient particularly when forced-convective gas flow is present. Since the gas flow affects the flow field and nucleate boiling heat transfer in the liquid film, it would also affect the rate of boiling entrainment. Thus, the effects of gas flow on the process of boiling entrainment were explored experimentally in this study. It was found that no boiling entrainment occurs at low heat flux but two types of boiling entrainment called ‘jet-type’ and ‘filament-type’ occur at higher heat flux. In the present experimental conditions, the minimum heat flux needed to cause the two types of boiling entrainment increased with an increase in the gas flow rate.

The ground source heat pump (GSHP) is a system that uses buried pipes to extract heat from the soil and release it to the soil. Underground heat exchangers were set to a length of 25 m and inserted into each of three water-filled bore holes. The purpose of this paper is to evaluate the performance of the GSHP using the direct expansion method in cooling mode. The performance was evaluated by the Coefficient of Performance (COP), which is determined by the ratio of the heat exchange to the power consumption of the compressor. The experimental results showed that the average COP was more than 8.2 in the cooling mode.

The cooling performance of ground source heat pump (GSHP) that use direct expansion method were obtained by an experiment. An underground heat exchanger with a three-branch copper tube was used in the GSHP. The GSHP also adopted a pouring water system into the borehole during high-load continuous operation. The output power of the heat pump is 6.8 kW in cooling operation. The depth of a borehole and the length of the three-branch copper tube was 30 m. The casing pipe were inserted into the borehole. Then, the U-shaped underground heat exchanger was inserted into the casing pipe filled with water. The average value of the obtained output power, power consumption, and System Coefficient of Performance during the cooling operation period was 10.0 kW, 1.3 kW, and 7.45, respectively.

Triangular pyramid type heat transfer surfaces were made as new type of heat transfer surface, and its low pressure pool boiling cooling performance was investigated experimentally. The saturation pressure cited was 15 kPa. Working fluid was pure water, and its liquid height was 25 mm. Two types of triangular pyramid type heat transfer surfaces were used, one with a pyramid size of 2.5 mm and the other with a pyramid size of 5.0 mm. The heat transfer performance of the triangular pyramidal surface with size of 2.5mm was better than that of 5.0 mm. The heat transfer coefficient was about 2.0 times higher with size of 2.5 mm and 1.8 times higher with size of 5.0 mm compared with the smooth surface. When comparing with the square pyramid types, the triangular pyramid types had a higher heat transfer coefficient than the square pyramid types.

Although the effect of radiant heat transfer is important for the natural convection field in large-scale systems, the influence of the radiation on the natural convection has not yet been clarified experimentally. This study is focusing to evaluate the mechanism of the effect of radiation on the convection field from the viewpoint of experimental and numerical analysis. In order to achieve the purpose, the Mach-Zehnder optical interferometer is used in this study to change the emissivity of the wall surface inside the rectangular cavity. Visualization measurement of changes in the natural convection boundary layer under the influence of radiation caused by this is performed.

Methane was issued from six nozzles with an inner diameter of 0.7 mm placed at each vertex of a regular hexagon to establish a lifted flame, of which flame holding characteristics were investigated. It was found that the lifted flames on the burner of six-nozzle with nozzle pitch from 8 mm to 14 mm, where the lifted flame was held on the center axis of six fuel jets, were more difficult to blow-off than a single nozzle burner. In the burners with nozzle pitch from 4 to 14 mm, the burner with nozzle pitch of 10 mm was the most difficult to blow-off and stably held in a relatively wide range of exit flow velocity, from 20 to 170 m/s.

Sauna bathing, which has attracted much attention in recent years, because it has t relaxation effect. On the other hand, the risk of heatstroke in saunas has not been evaluated, and it is necessary to evaluate the heat transfer characteristics around the human body against the heatstroke. To solve this problem the heat transfer inside the sauna room was evaluated by numerical simulation using OpenFOAM. To understand the radiative heat flux which propagates to the human body, the mean radiative temperature inside the sauna room was evaluated.

To improve the thermal efficiency of automobile engines, it is necessary to reduce cooling loss by clarifying the heat transfer mechanism. The purpose of this study is to develop a general measurement method for investigating the relationship between flow and heat transfer to quantitatively evaluate the cooling loss. We investigated the relationship between the flow near the wall and the heat flux using a hot wire anemometer and a MEMS heat flux sensor in a special field where a simple flow structure can be reproduced, i.e. a collision of laminar vortex ring to the wall. Double peak in the heat flux is observed during the vortex passage on the sensor.

ZnO/CuO nanowire (NW) catalysts for methanol steam reforming are prepared and evaluated for hydrogen production for fuel cells. NW catalysts are expected to be more durable than conventional nanoparticle catalysts due to their fine structure that prevents agglomeration. In this study, we introduce a hierarchical structure to the NWs to increase the active surface area. The NW catalysts are prepared by hydrothermally synthesizing ZnO NWs and coating them with CuO. The reforming tests indicate that the coexistence of CuO and ZnO under appropriate conditions and the hierarchical structure improve the catalytic performance.

In recent, environmental regulations have been tightened, and the development and introduction of Battery Electric Vehicles are accelerating. Since not only the passenger but also the electronic equipment cooling is required for car air conditioners, it is necessary to increase the cooling performance of evaporators. In addition, since the power saving is required for car air conditioners to improve the cruising range of Battery Electric Vehicles, it is necessary to save the cooling performance by zone air conditioner. We have developed a new structure that can achieve both cooling performance at high flow rates and uniform air temperature distribution at low flow rates by using the refrigerant flow that can reduce the pressure drop inside the evaporator.

In this study, in order to develop the film flow model for critical heat flux prediction in a downward flow, a double liquid film extraction method was applied to a forced flow boiling system. In addition, characteristics of liquid droplet at the downstream of the first liquid film extraction section were simultaneously observed by high-speed camera. As the results, the liquid film mass flux at heating section exit and the droplet transfer coefficients in downward flow were successfully obtained. The obtained droplet transfer coefficients in downward flow correlated with not droplet concentration but volumetric flux, and these characteristics may be correlated with the unique liquid droplet movement of downward flow.

Systematic PIV measurements of turbulent channel flows over rib-roughened porous media are conducted to find universal correlations for the combined effects of the roughness and the wall-permeability on turbulence. Square porous ribs whose height k is 10% of the channel height are set at regular intervals, of w/k=1,3,7,9,19. Three kinds of porous media applied have the same porosities, 0.95, but different mean pore diameters. By fitting the mean velocity profiles to the logarithmic law, discussions of the log-law parameters are conducted. It is then confirmed that the zero-plane displacement has a linear relationship with the roughness scale and that the newly determined effective displacement well correlates to the mean pore diameter.

Our laboratory has proposed Self-Water Management Separator (SWMS) with a bypass channel in the separator to progress the system efficiency and reduce the system cost. Because SWMS improves water-management- issue of Polymer Electrolyte Fuel Cells (PEFC) by reusing water generated within the same cell, it can achieve the improvement and the lowering the cost of efficiency. This study aims to select the optimum packing material from polyvinyl alcohol (PVA) sponge, diatomite powder, cellulose fiber insulation, and EM diatomite grain. Therefore, we selected PVA from viewpoints of cell performance and handling ability.

We have been developing High Functional Direct Carbonate Fuel Cell (HF-DCFC) composed of Molten Salts Gasification and Tubular Molten Carbonate Fuel Cell (T-MCFC), can use an organic waste as fuel directly. The previous study has established the manufacturing method of a T-MCFC single cell supported by a stainless tube of φ9. Aiming at commercialization of HF-DCFC, T-MCFC should be stacked to output a high power. We proposed that the socket type T-MCFC stack was composed of connecting several single cells supported by alumina tube to avoid short circuit. However, because the crack was caused in both electrodes of this socket type, it was able hardly to generate electricity due to gas cross leakage through these cracks. These failure factors were confirmed by manufacturing the stack with a stainless support tube of φ19. We have developed a new stack composed of connecting two single cells supported by stainless tube and alumina-joint.

We have been developing High Functional Direct Carbon Fuel Cell (HF-DCFC) composed of molten salts gasification system and tubular molten carbonate fuel cell (T-MCFC). This paper aims to evaluate the fundamental characteristics of HF-DCFC using wood pellet and the optimum electrolyte loading ratio. As a result, we were able to confirm that the cell performance of T-MCFC depended on electrolyte loading ratio. We were able to confirm that HF-DCFC is effective enough as the distributed power source and the waste disposal equipment if wood pellet was supplied to HF-DCFC continuously, because the electric power of HF-DCFC was enhanced even if fuel gas utilization ratio increased.

An evaporation of droplet reaches a minimum time at a temperature of hot surface beyond the saturation temperature. Most of researches have mainly focused on the temperature at the minimum time, only. This paper proposed an exact solution to calculate heat flux after a time when the droplet starts contact with the hot surface. The calculated heat flux until a time of about 1 ms when the droplet starts evaporating on the contact surface is found to be very close to the critical heat flux for subcooled pool boiling at the droplet temperature. The average heat flux at the minimum time is firstly determined for the hot surface from which the corresponding initial surface temperature is dependently determined.

The multiple-ion-probe method detects flames using a plurality of ion probes installed on the wall of a combustion chamber and by reconstructing the dynamic behavior of the flame front along the wall. This study aims to establish a method to automatically determine the characteristics of combustion for each mixture using a multiple-ion-probe measurement system. From the obtained individual experimental data, twelve types of features were extracted. We compared the features extracted from the output data of the multiple-ion probe with the different combustion modes obtained in the series of experiments; we found that a few of the features strongly responded to specific propagation states.

The triboelectric generator consists of triboelectric charging and electrostatic induction. The generator is characterized by its light weight, flexibility to use a wide range of materials, and the ability to achieve miniaturization through microfabrication technology. Extracting the static electricity generated in our daily lives as electric power can be considered as a sustainable energy source for the future. In this study, we will measure the amount of power generated when the number of blades, rotational speed, torque, material, and size of the generator are varied, and discuss the power generation mechanism in terms of capacitance and external load.

To improve the performance of the plate heat exchanger for OTEC, the anodic oxidation aluminum heat plate has been adopted as a heat exchange plate. However, there are no adoption of the anodic oxidation aluminum plate as the plate heat exchanger. To measure of boiling heat transfer characteristics of aluminum plate, the observation of boiling phenomena of FC-72 as a working fluid on plate heat exchanger which installed sight glass. In the present study, it was also clarified that the characteristics of boiling phenomena on the herringbone-type and smooth plate.

In a general electric Environmental-Control-System(ECS), the conditioned air supplied inside the cabin of aircraft is discharged outside without being effectively used. The air passed through the cabin obtains a non-negligible amount of heat from electronic devices and passengers. Therefore, in this research, we propose the use of an electric turbo compressor that recovers energy with a turbine and returns power to the electric compressor before discarding air. We will investigate a thermo dynamic analysis to obtain the energy recovery rate under the configuration with two electric turbo compressor.

The objectives of this study are to observe and investigate characteristics of near-wall turbulent heat transfer phenomena caused by a round impinging jet by means of direct numerical simulation (DNS). In order to accurately investigate such phenomena, DNS is very useful tool as far as we know. The DNS of near-wall turbulent heat transfer phenomena caused by round impinging jet with isothermal impingement wall is conducted under conditions of various impingement distances to investigate effect of impingement distance. In a round impinging jet, since a bulk flow rate decreases toward streamwise direction on the impingement wall due to increase in the cross-sectional area, heat transfer is also suppressed in the down-stream region on it. Thus, because a remarkable enhancement of heat transfer occurs around a stagnation point, it is important to know the effect of impingement distance for the near-wall heat transfer phenomena. As results of DNS, both detailed characteristics and statistics of near-wall turbulent heat transfer phenomena caused by a round impinging jet are clearly obtained.

Polymer Electrolyte Fuel Cells are expected to be widly used as clean energy source. A doctor blade method, generally manufacturing method of PEFC, it has problems such as a bad dispersibility of Pt catalyst and a difficult thickness control in precisely. Our laboratory proposes applying an inkjet coating printing to the CL manufacturing process to solve these problems. The cell performance of CL composed of a multilayer to obtain enough thickness was lower than that of single layer. The reason was to have obstructed the electron transport property by separating ionomer and Pt in the catalyst ink. The cell performance has been enhanced by the formation of the CL where I/C ratio was changed from GDL to the direction of the membrane.