It is known that some alcohol such as butanol shows peculiar temperature dependence of surface tension. Thus, thermo-capillary force acts for the liquid to wet the heated surface, so that solutions are sometimes called as "Self-rewetting Liquids". In this paper, a boiling experiment of butanol aqueous solution was performed on a wire. A heated wire is easy to observe the phenomena and easy to address the fundamental issues of boiling. Bubbling aspects and bulk liquids component were measured utilizing high-speed video camera and microscope lens Critical Heat Flux of Butanol aqueous solution at saturated temperature is enhanced from 2 to 3.5 times higher than that of pure water. Two types of boiling aspects were observed in this paper. Boiling mode of butanol aqueous solution is named as "Small bubble Emission Boiling (SEB). SEB is very high heat flux and bubble is small size, and many in number Bubbles are hard to coalescence.

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In the present study we observed Marangoni convection at the gas liquid interface of alcohol aqueous solution. It was driven by the surface tension variation caused by temperature gradient along the bubble surface. Numerical simulation was performed about pure water and butanol aqueous solution to compare with the result of experiment. It was found from this study that the direction of Marangoni convection in using butanol aqueous solution (7.15wt%) was toward heated surface. Moreover, the tendency of the experiment and the numerical simulation was the same in terms of flow pattern and its temperature dependence.

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We applied butanol aqueous solution, pure water and propanol aqueous solution to boiling with impinging flow in mini channel and compared the result with each other. The butanol aqueous solution realized higher dryout heat flux than others. Besides, the boiling bubbles behaved differently depending on the kind of the solution. In the case of butanol aqueous solution, the boiling bubble became smaller and released from the heated surface more smoothly than others. On the other hand, we started to construct numerical model in order to analyze the distribution of concentration in the vicinity of the bubbles.

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In this research, flow pattern and pressure drop characteristics of kerosene-water two phase flow in horizontal mini-channel was investigated. The tube diameter was 0.53 mm, and it was made from pyrex glass. The volumetric fluxes of each liquids were set between 0.05 and 0.6 m/s. The several flow patterns were observed in mini-channel, i.e. Droplet flow, Slug flow, Slug-Annular flow, Annular flow, Parallel flow and Kerosene slug flow. The transition of flow pattern has been explained by using Weber number of each phase. The pressure drop has shown a good agreement with Lockhart-Martinelli correlation, moreover the adaptability of the moving film model to the estimation of pressure in the slug flow regime has been confirmed.

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Pool boiling heat transfer experiments were performed for small heat transfer surfaces; the diameter D = 20 mm, 3.0 mm, 2.0 mm and 1.0 mm at 0.1 MPa by using ethanol. The overall trend of the boiling was similar to what had been observed for a usual size heat transfer surface. As the diameter of the heat transfer surface became small, the heat transfer coefficient and also the critical heat flux were greatly enhanced.

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We developed special T-type temperature sensors which sharing a common positive pole. 6 temperature sensors were placed at a depth of 1.6 μm beneath the surface of interest, at distances of 0.1mm, 0.625mm, 0.819mm, 0.919mm, 9.228 and 12.204 mm from the center of boiling cavity. The sensors were used to measure the temperature distribution under a boiling bubble. With using the measured temperature data, we solved the inverse heat conduction problem to derive the surface heat flux and surface temperature during a boiling cycle.

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Boiling feature on a copper surface with hydrophobic coating of spotted pattern has been studied. Nucleate boiling begins at hydrophobic region at low superheating and an overshoot of superheating in boiling incipience is not observed. Heat transfer on the surface of spotted pattern is better than mirror surface. At low heat flux, generated bubble size depends on the spotted size and heat transfer is enhanced by subcooling effect. The hydrophobic coat region is effective to avoid overshoot in the low superheat region.

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In the present study, we measured liquid phase temperature field during pool boiling with the laser interferometry, and tried to directly evaluate the heat transfer from the liquid to the bubble. The MEMS thermal sensor which can control the bubble generation was used as the heating surface, and the thermal field around the isolated bubble without bubble-bubble interaction was measured. The interferometric method successfully visualized macroscopic thermal field in the liquid phase such as swell of the thermal boundary layer with the bubble growth and the hot wake accompanied by the rising bubble. However the temperature gradient driving the evaporative heat transfer in the vicinity of the interface was not able to be measured due to shortage of the spatial resolution. Two-dimensional thermal fluid analysis demonstrated that the improvement in resolution by one order of magnitude will be required in the future work.

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This paper presents an experimental investigation on forced convective boiling of refrigerant HCFC123 in a mini-tube, and visualization of boiling phenomena at the onset points of nucleate boiling is conducted. It was indicated in the former report that heat transfer characteristics of forced convective boiling in mini-tubes, of which inner diameter is φ0.51mm and φ0.30mm, were different from those in conventional tubes. In order to clarify this difference of heat transfer characteristics, bubble formation and growth at the onset points of nucleate boiling were observed and examined, using a glass tube on which ITO film is formed. For low heat flux, an isolated bubble grows up to occupy the whole tube cross section, and flows in the form such as a bullet. As heat flux becomes larger, plural bubbles grow to coalesce into a long vapor plug, and evaporation through liquid film between the vapor plug and the inner tube surface becomes dominant.

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The major reason for the lack of data in the multiphase flow lies in the difficulties in measuring the flow quantities of the multiple phases simultaneously. The difference in the refractive indices makes the visualization almost impossible. Presently, the simultaneous visualization has been carried out about the both phases of the liquid-liquid two-phase flow by adjusting the refractive indices of both phases. The PIV measurement has been carried out for a falling water droplet near the wall in the stationary oil. The results reveal the typical features of the effect on the convection around and inside of a droplet.

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This paper presents experimental investigations of effects of the surface roughness, impinging velocity, and diameter of a droplet on the cooling rate in water spray cooling. The sample surface used is SUS304 cylinder with different roughness, Ra 0.04 (Mirror), 0.2, 3, and 10. The droplet diameter and velocity are independently controlled in ranges of 300-700 μm and 1.0-5.0 m/s, respectively. The cooling rate increases with decrease in droplet diameter when the flow rate of water is constant. The cooling rate also increases with impinging velocity and surface roughness. The effect of the velocity difference arises in the film boiling region.

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A challenge developing surface temperature sensor with short response time below the order of 1 ms has been done to investigate wetting or non-wetting phenomena on a hot surface. A hot junction of Chromel-Nickel thermocouple was formed at 3μm below the surface with electroless nickel plating. Combination of thermoelectric materials and structure of the sensor are carefully considered to realize the required response time and indication accuracy.

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In this study, effects of droplet flow density and mean droplet diameter on film boiling heat transfer and collapse temperature of film boiling (MHF point temperature) of spray nozzle cooling were examined experimentally. A test heater was Nichrome foil with 0.2 mm thickness, 5 mm width and 100 mm length. The droplet flow density was 50, 100, and 200 l/min m^2, respectively. The mean diameter of droplet was 198, 301,352,415, and 472μm, respectively. The test heater was heated DC current through DC power supply. The temperature of test heater was measured by using a K-type thermocouple. The present experimental results showed that film boiling heat transfer was increasing with mean droplet diameter. The effect of mean droplet diameter to MHF point temperature was weak. On the other hand, film boiling heat transfer and MHF point temperature increased with increasing droplet flow density.

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The limit of heat flux estimation by 3-D inverse heat conduction was investigated for a system in which constant annular heat flux moving from the center to the periphery is removed from the end surface of a columnar block. Temperatures of sensor positions were calculated through axi-symmetric situation and 76 temperatures at an equilateral 2-D locations are used to estimate heat flux distribution across the surface. The product of heat flux and width can be accurately estimated independent of the transverse velocity of heat flux pulse. Heat flux estimation is valid when the width of heat flux pulse is less than twice of temperature sensor depth and the pitch of two neighboring sensors.

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The purpose of this study is to develop the latent heat storage system using erythritol as a latent heat storage material. In this study, the direct contact melting and solidification behaviors between oil and erythritol were visualized in order to investigate the characteristics of heat storage and release of erythritol. The experimental results show that the increase of erythritol bubbles was inhibited by using a perforated aluminum lattice. And it is clear that solidification height of erithritol with the lattice was lower than the height without the lattice.

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The present paper is suggested to reuse waste heat in middle temperature region (100℃〜250℃) from factories. The purpose of this paper is comparing the melting and solidification characteristics of the mixture of mannitol and erythritol (C_M=70mass%, mannitol[70mass%]: erythritol[30mass%]) and mannitol as a PCM in a vessel with pipe heat exchanger. The experimental result was confirmed that the heat storage speed of the C_M=70mass% mixture is faster than that of the mannitol with an average 1.5 times in each flow rate of oil.

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It is at now that addition of Carbon Nanotube (CNT) changes the physical and thermal description of the added substance. It is well known that we investigated the effect of CNT content of suspension (0.35〜0.5 wt%) and heating time to evaluate of fundamental temperature data of heating medium. In the case of unfilled CNT system, the suspension temperature has reached 65℃, 90℃ and 120℃ for 7min,12min and 20min,respectively. The results of utilizing this method effectively thought that it was manufacture of the generator of small steam, and made small steamy generating equipment as an experiment.

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Concerning thermal conductivity measurement of solids, there are many sorts of methods like Guarded hot plate method, Laser flash method, and so on. And using these methods, one can perform reliable and high-precision measurement. However, depending on the methods, fairly high cost and/or skill are required to obtain satisfactory results, In the present study, for the purpose of developing a simple thermal conductivity measuring method for thin metal plate, a steady-state method in accordance with the Fourier's law of heat conduction has been proposed. Furthermore, the apparatus constant has been evaluated based on the measured results using copper C1100, aluminum alloy A1050 and A5052 with known thermal conductivity.

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As part of the effort to elucidate the potential of steam-water mixed spray, a high-speed multi-phase thermal fluid, we conducted a series of experiments with resist-coated silicon wafers as the target of the spray. We measured the amount of the resist removed by the spray, and found that it depends on several parameters such as the thickness and mechanical strength of the resist. The results suggest that the resist removal by the spray is essentially a physical process, and the impact of the spray can be controlled, implying the application potentiality of the spray.

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The purpose of the present study is to establish the basic technology to achieve the CO_2 reduction and the hydrogen production by using exhaust gas, waste steam, and sawdust. As the method, we used shock heating by the gas shock waves driven from high pressure gas. The experimental apparatus is standard shock tube. As a result, hydrogen concentration increased by getting small size and adding the sawdust and rising the shock heating temperature. The highest hydrogen concentration is about 30%. The particle diameter of the sawdust should be adjusted a decrease of CO_2 and a high hydrogen concentration to about 30% or less, and the shock heating temperature be adjusted to about 1200K or more.

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In heterogeneous interface systems such as two-phase interfaces and membranes, mass transport in the vicinity of the interfaces exhibits complicated characteristics and an essential understanding of their mechanism is of critical importance. In the present study, molecular dynamics simulations of silica-water and silica-IPA (iso-propyl alcohol) interfaces have been performed in order to investigate molecular-scale structure of the adsorption layers of liquid molecules and molecular transport characteristics. As typical terminations of silica surface, H- and OH-terminated ones were used and behaviors of liquid water and IPA molecules in the vicinity of these surfaces were analyzed. Self-diffusion coefficients in the direction parallel to the interface were measured and the mass transfer properties were discussed.

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An ice slurry, which is a mixture of fine ice particles and liquid has both very high heat storage performance and fluidity. The objective of the present study is to investigate the heat transport mechanism of the ice slurry when an ice particle is just close to the area on horizontal heated surface. Experiments were carried out for a variety of the flow velocity and solid fraction. The results indicated that the contribution of latent heat to heat transport of ice slurry increased on a bottom side heated surface with the increase in flow velocity, while it decreased on a top side heated surface as the flow velocity increased.

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The moisture thermal control air-cleaning method where sample air is continuously humidified with heating and dehumidified by cooling removes suspended particulate matter, SPM, from the air. This paper reports the removal characteristic of this method on SPM. A closed circulating system composed of a thermal moisture air cleaning equipment, a tank, a flow adjustment system and ducts was made and the time variation in SPM concentration was measured. The result showed continuous SPM reduction with time and the convergence of the SPM concentration. The convergence was due to equilibrium between the removal effects and leakage from outside. The variation tendency was modeled by the equation that expresses reduction in the air cleaning unit, the flow adjustment system the tank and the ducts and leakage from outside. The model showed that the important factors of this system were removal ratio of the thermal moisture swing operation and air flow rate.

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Two types of the optical indicators with light reflection and diffraction were proposed and verified. The thermal magic mirror used the light reflection. The thermal magic mirror indicates variation of the temperature as a sign visualized by light reflection pattern which changed with thermal expansion of microstructure on the device. In the experiment, the thermal magic mirror showed the sign on a screen above a specific temperature level. The holographic indicator is the diffraction type optical indicator. Test hologram was fabricated by computer-generated hologram and MEMS processes. Also, principle of holographic indicator was proposed and simulated by computer-generated hologram. If the holographic indicator was stretched by physical external force, the holographic image was changed to blurred image.

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Endoscopic PIV has been developed to measure flows in opaque equipment. It is however difficult to measure velocities near the edge of the field of view in the endoscopic PIV due to the Lagrangian nature of PIV. The authors developed an Eulerian velocimetry, that is, spatial filter velocimetry (SFV) to realize the simultaneous multipoint measurement of velocity with a high spatial resolution and high accuracy. In this study, we visualized natural convection of water in a pan heated by a cooking stove using a high-speed video camera with a borescope. The velocity distribution in the field of view of the borescope is evaluated by SFV to examine applicability of SFV to measurement of a velocity distribution from the borescope images. The experimental results indicated that SFV can measure the velocity accurately at arbitrary multiple points in the filed of view. The results also demonstrated the high applicability of SFV to the whole field measurement of velocity in the field of view of endoscopic visualization.

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In response to today's environmental and energy issues, the civilian sector desires a reduction of CO2 emissions as well as energy saving. In order to deal with such issues, this study will effectively use existing waste heat such as cogeneration systems, boilers and so on. Therefore, power generation by Brayton cycle machine and waste heat recovery systems (hot water supply and heat-driven air-conditioning equipment) are used for research and development. Here, in the development of integrated 500W Brayton engine generator, verification of operating principle and characterization of component will be announced.

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Discharge characteristics of multi-phase AC arc were investigated for the innovative in-flight glass melting technology. The discharge behavior were studied by using high-speed video observation and the analysis of the obtained images for 2, 6, 12-phase AC arcs. The luminance area of the arc and its fluctuation were estimated to investigate the periodical characteristics of the multi-phase AC arc. Obtained results indicated that an increase of the number of the phase leads to large luminance area and faster fluctuation. Consequently, the 12-phase multi-phase AC arc is suitable for the powder heat treatment.

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In this study, direct decomposition of waste oil was attempted by use of plasma-assisted combustion under reduced pressure. Experiments were performed to compare the emission spectrum, composition and production of the gases generated by plasma-assisted combustion and reduced-pressure combustion. It was found that plasma-assisted combustion increased the total emission intensity, and that OH emission intensity was increased more than 30 times. In addition, H2 and CO increased, whereas CO2 decreased in the generated gas. This study showed the decomposition characteristics of waste oil during plasma-assisted combustion under reduced pressure, and it indicated the possibility that it can be used as a new waste-treatment technology.

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RF thermal plasma was used to prepare nano-sized boron-rich compounds and the mechanism of nanoparticle formation was investigated by estimating the homogeneous nucleation rate. In order to synthesize aluminum dodecaboride (AlB_<12>), the premixed feed powders in different compositions of aluminum and boron were injected into the thermal plasma operated in different working gas conditions. High boron-ratio and thermal conductive helium were favorable to enhance AlB_<12> synthesis in final product due to higher boiling point of boron than aluminum. In the nanoparticle synthesis process, vaporized raw materials in the high temperature region were rapidly cooled and nucleate in the plasma tail region with a steep temperature gradient. At this point it was predicted that boron nucleates first and then aluminum nucleates. Therefore, AlB_<12> is formed by condensation of aluminum to the boron nuclei.

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When an activated cokes bed is irradiated by microwave, it is observed that nonequilibrium argon plasma is induced in the downstream of the bed with low electromagnetic power under atmospheric pressure. This paper presents the fundamental behavior as well as direct decomposition performance of nitrogen monoxide (NO) in the microwave plasma without catalysis. Argon plasma was generated stably with a broad distribution in the reaction zone in the downstream of the activated particle packed bed under a microwave field beyond a critical power. NO contained in argon stream was significantly decomposed in the stable plasma and the conversion was achieved over 90% for 1040 ppm inlet NO content without any catalyst and reducing agent. The effect of de-NO conversion was improved by addition of ammonia.

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Long DC arc plasma was generated in the distance of 400 mm with argon under the atmospheric pressure. It has some typical features of larger thermal plasma volume providing long processing time. High speed video and digital oscilloscope were used to capture the arc column fluctuation and with simultaneous measurement of the arc voltage for analyzing arc column characteristics. Arc column radiation intensity was increased with an increase of gas flow rate in spite of the decrease of the arc column voltage. The interesting phenomenon of the arc voltage decreased according to gas flow rate in the argon arc plasma that was occurred by the thermal pinch. It is very important for industrial application that the arc column core temperature keeping constant between electrodes.

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The purpose of this research is to develop a process to use the plasma decomposition of clathrate hydrates to produce fuel gas. An ordinary microwave (MW) oven is used as the source of 2.45 GHz MW radiation under atmospheric-pressure. The plasma decomposition of the hydrates could pave the way for a new utilization of atmospheric pressure plasma. Cyclopentane (CP) hydrate formed at atmospheric pressure was decomposed by plasma in a MW oven generating gas with a content of 65% hydrogen, 12% CO, and 8% CO_2. About 32% of the MW input power was consumed to decompose the hydrate.

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The purpose of this study is to investigate the application of DC water plasmas on liquid waste decomposition. Decomposition system of liquid waste by DC water plasma at atmospheric pressure has been developed. 1-Decanol emulsion used a model substance of water-insoluble organic compound was mixed with emulsifier (Tween 60) for plasma supporting gas. The decomposed gas was investigated with gas chromatography and mass spectroscopy. The main gases after the decomposition were H_2, CO, and CO_2. The mole fraction of H_2 in the decomposition gas was 68% in the decomposition gas. The water plasma system can be used for industrial application of liquid waste decomposition.

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This study focuses on the effect of the compression ratio on the in-cylinder deposit formation of a diesel engine fueled with straight vegetable oil (SVO). Two-dimensional thickness distributions of the carbon deposits on the cylinder head wall were measured by a laser displacement meter after continuous operation for 4 hours. The experiment result shows that a lot of carbon accumulated along the injection directions especially in the case of low compression ratio. Also, it was shown that the higher compression ratio, the lower the deposit accumulation is.

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To study the effect of the ethanol concentration gradient on knocking in n-heptane/air homogeneous mixture, we carried out the compression and auto-ignition experiment by using rapid compression machine (RCM). The luminescence of flame was captured by High speed camera. Experimental results were that the luminescence progressed from top (lean) to bottom (rich) in cylinder with the ethanol concentration gradient and when the ethanol concentration gradient was over 0.1, the knock intensity was smaller than that of homogeneously mixed ethanol.

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City electric power decentralize reciprocating engine is fit to use to small scale power generation for home and so on. Fuel diversity is important and the efficiency is the most important. This paper shows the effect on thermal efficiency of mixtures rate. As a result, ethanol/gasoline mixture thermal efficiency is increase as mixture rate increase, kerosene/gasoline mixture thermal efficiency is hardly changed by mixture rate. However, both of fuel occurred nocking and the engine power was limited.

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In order to investigate the influence of the cavitation on the spray characteristics of the biodiesel, a spray nozzle flow visualization experiment system was established, images of nozzle flows and sprays under different pressure conditions were recorded by a high speed camera. For comparison, gas oil and water were employed. The experimental results showed that, with the increasing of injection pressure, the cavitation region extended from entrance to interior along the flowing direction in the spray nozzle. When the injection pressure continued to increase, the cavitation region extended to the outside of spray nozzle and a jet flow was caused, then spray cone angle decreased rapidly to only half of the maximum spray cone angle.

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A jet ignition method by flame jet is proposed to the combustion of lean mixture. It is worried that the heat loss of the jet ignition method becomes bigger than that of conventional ignition, because the velocity of the flame jet is very fast and the temperature of it is very high. It is thought that the heat flux at the nozzle becomes bigger than that of other locations. In this report, the heat flux distribution at the nozzle inside is investigated. The results are that the flame pattern and the nozzle diameter affect the heat flux. The smaller the nozzle diameter is, the bigger the heat flux at the nozzle is.

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Cylinder pressure is used for the closed-loop ignition angle control of a gasoline engine. This paper focused on the crank angle position where the maximum cylinder pressure reached (θPmax) and the relationship between the θPmax and the ignition angle. This closed-loop control set the θPmax a target value with an initial ignition angle and does not need a detailed ignition angle map. Response time and deflection with the target value are examined with a test bench. A simulation with AVL BOOST was performed to evaluate the experimental results.

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Burner low-temperature flames were established on a powling burner with a diethyl-ether/toluene/air (ethylene content in mixture: 5000 ppm and 10000 ppm) at an equivalence ratio of 2.0, under the atmospheric pressure, in order to better understand the low-temperature oxidation mechanism. Aromatic hydrocarbons and unsaturated aliphatic hydrocarbons measurement are preformed by a liquid- and gas-chromatograph. The temperature in the low-temperature flames were measured using a fine thermocouple. Ethylene addition retarded the low-flame appearance. The generation of the aromatic hydrocarbons is promoted by adding the ethylene only in the yellow column.

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The temperature profile of the supersonic jet from the nozzle of the high enthalpy combustion wind tunnel is measured by two-band emission method. Carbon dioxide is used as the doping material and two infrared emissions are recorded with thermo camera through the narrow band pass filters. The emission intensity profiles are converted to the temperature profile with the infrared emission database calculated by RADCAL program in advance. The obtained temperature profile was consistent with the expected profile and temperature range, and it is verified that this method is useful for capturing supersonic flow field.

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It is extremely important to save energy for prevention of global warming. New generation automotive engine is made up by high compression ratio and low friction by small engine for better fuel consumption. However with higher compression increasing the piston's temperature exceeds a melting point of the aluminum and a piston is damaged. The measurement of good piston temperature of the precision is very important for higher compression piston and good fuel consumption. In this paper we made the measurement of good piston temperature of the precision by RF-MEMS systems.

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This paper investigated the change of the number of aerobic/anaerobic bacteria alive in refuse derived fuel (RDF) with the progress of incubation and discussed its relationship to the change of hydrogen gas production in order to understand the mechanism of hydrogen gas production from RDF. This paper used Kuwana and Sakura; two kinds of RDFs that showed the significant difference in hydrogen gas production among the RDFs collected at 7 locations. As a result, it was found that the change of number of aerobic/anaerobic bacteria was similar with that of hydrogen gas production with the progress of incubation.

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In this study, a numerical simulation on the freezing and thawing process is proposed to evaluate the effects of freezing-point depression on the quality of frozen/thawed aqueous solution. Directional solidification processes of dilute solutions are simulated by considering solute redistribution at solid/liquid interface. The calculation results indicate that the solid/liquid interface shows a different behavior from the flat interface in the case of high rejection of solute. It is also found that concentrated areas of the frozen sample melts more quickly.

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This paper describes heating properties of resonant cavity applicator with 3-D FEM knee model. We proposed a new heating method for knee rheumatism rehabilitation. In this paper, first, a method of reconstruct a 3-D anatomical human knee model from 2-D MRI and X-ray CT images was described. Second, proposed heating method was described. Third, we estimated a specific absorption rate (SAR) inside the anatomical human knee model by the finite element method (FEM). From these results, it was found that our method is useful to heat deep knee region.

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