This paper proposes a non-intrusive measurement technique for the ion concentration distributions at liquid-solid interfaces in microchannel flow using total internal reflection Raman imaging. The technique uses spontaneous Raman scattering excited by evanescent wave. The evanescent wave was generated at a glass-solution interface by total internal reflection using an optical system employing two prisms. The calibration result showed a linear relationship between the Raman intensity ratio and the ion concentration of NH_4Cl deuterium oxide solution. Using this calibration, further experiments will be performed for non-intrusive measurement of the ion concentration distributions in mixing area of D_2O and NH4Cl deuterium oxide solution at liquid-solid interfaces.

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In this paper, molecular behavior simulations considering non-intrusive two laser measurements were performed to investigate the influence of the heat from the laser. Virtual particle was released into microchannel and particle trajectory was changed at nanoscale by the heat from laser. In microscale laser measurement concentration distribution by simulation had no change with the heat from laser. However, only in nanoscale imaging, Raman scattering intensity from the virtual particle was increased because of the virtual particle behavior. The influences on molecular diffusion phenomena in nano/microscale by the heat of the laser were successfully explained.

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Adsorption heat pump system is expected to increase energy efficiency. However, insufficient performance of the system is still a critical issue. To improve the efficiency, fundamental phenomena of water adsorption and desorption on silica gel need to be elucidated. In this study, adsorption and desorption process on silica gel were investigated by using X-ray computed tomography. As a result, water distribution on silica gel during adsorption and desorption process was visualized successfully. The visualized images indicated that the desorption process occurs uniformly in the silica gel. On the other hand, the non-uniform water distribution was observed in the adsorption process. It suggested that the outer part of the silica gel adsorbed more water than the inner part.

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We propose the thermal-mode spectroscopy (TMS), a new experimental technique for thermal conductivity of minute specimen. The TMS method is based on the excitation and detection of "thermal modes" using an optical pump-probe technique. All existing methods are based on "heat transport", and they are unsuitable for minute and high-heat-diffusivity specimens because of many ambiguous parameters. Thermal conduction is recognized as "overdamping" phenomenon of thermal wave, and it is characterized by the temperature relaxation time (corresponding to eigenvalue), which is a function of dimensions and thermal diffusivity of the specimen. By solving the eigenvalue problem of heat equation, we theoretically obtain the relaxation time and then the thermal conductivity. Because the TMS method needs no ambiguous parameters owing to the eigenvalue method and the non-contact measurement, we can determine thermal conductivity more accurately than other previous methods.

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For obtaining the data that contributes to propose detailed chemical reaction mechanism including the evaporation process of the liquid fuel, experimental study of counter-flow pool combustion was conducted. The one-dimensional diffusion flame was formed in this configuration. With respect to the counter-flow pool combustion of ethanol in this study, we carried out the temperature measurement by thermocouple and OH measurement by laser induced fluorescence method. The results obtained by the experiments were compared with the numerical simulation with OPPDIF/CHEMKIN-Pro. Results showed good agreement with experimental results and numerical results. In addition, we also tried numerical simulation of hydrazine as a realistic fuel.

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The purpose of this study is to investigate compounds of tar in which are produced in a fluidized bed gasifier. The tar compounds (M.W<300) were identified by gas chromatograph mass spectrometer (GC/MS) and gas chromatograph (GC-FID). The results of field desorption mass spectrometry (FD-MS) of tar showed that m/z increased by 24 when adding aromatic-ring to polycyclic aromatic hydrocarbon (PAH). Also, it was found that m/z changed 26 in difference to the bonding position of aromatic-ring with PAH. By applying this law to Benzo[ghi]perylene (M.W. 276), it was found that main compounds of tar were PAH.

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Temperature and heat of reactions have been measured during fast pyrolysis of biomass powder packed bed. For cellulose powder, temperature at the center of the bed, T_C, increased monotonously with time due to thermal conduction for T_C < 500K. The temperature increased slowly with time due to endothermic decomposition of cellulose for 500 K < T_C < 600 K. On other hand, exothermic behaviors for xylan powder and lignin one were significantly observed at TC > 500 K and at T_C > 600 K, respectively. Furthermore, numerical simulation of fast pyrolysis of cellulose powder packed has been conducted.

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Heat and mass transfer during co-pyrolysis of packed bed of pulverized coal and polystyrene have been investigated. Mass fraction of the pulverized coal in the mixed powder and polystyrene was changed from 0.00 to 1.00. The temperature in the packed bed of pulverized coal increased monotonously with time and approached to the steady state value of it except for until 375 K due to the evaporation of water. On the other hand, temperature in the packed bed of polystyrene bed increased initially with time and then didn't change due to endothermic pyrolysis of it at 450K. After that the temperature increased again and approached to the steady state value. The co-pyrolysis rate could controlled by the decomposition of pulverized coal when the mass fraction of the coal was greater than 0.25.

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Emulsion is a mixture of two substances which isn't soluble to each other. When the water is continuous phase and very fine oil particles are dispersed in the continuous phase, the emulsion is defined as O/W emulsion. The O/W emulsions have been used in various fields, such as food processing and chemical industry. However, the flow and heat transfer characteristics of O/W emulsion have not been clarified yet. Therefore, in this study, natural-convectional of the O/W emulsion in a rectangular container was investigated experimentally. The particle size of the oil particles and temperature difference between heating plates were varied as the experimental parameters, and the effect of the parameters on stratification condition was revealed.

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Emulsion is a mixture of two materials that generally don't mix with each other. It has been used in various fields, such as food, cosmetics, paints, pharmaceuticals, chemical products, and thermal storage media. Oil-water emulsion has a lot of very small oil particles in water. In this study, since the particle might affect the flow and heat transfer characteristics in microchannel, the flow and heat transfer characteristics is investigated experimentally. Emulsion consists of pure water, silicone oil, and surfactant. The combination of the ratio and kind of each material and the channel width was varied as experimental parameters. As the result, the effect of these parameters on emulsion's apparent viscosity and Nusselt number were clarified.

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A model has been developed to investigate the evaporation behavior of water droplets in a uniform duct flow under gas turbine environments. It is assumed that the change of water droplet temperature is caused by convective heat transfer through droplet surface. The temperature of a water droplet has been calculated by treating the droplet as a lumped mass with a representative temperature uniformly distributed in the droplet. The proposed model consists of two steps. The 1st step is the heat transfer calculation between a water droplet and surrounding air flow and the 2nd step is the calculation to take the latent heat of vaporization into consideration. The evaporation rate is calculated based upon mass transfer between water droplet and surrounding air flow.

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The effect of working fluid properties on gas turbine performance has been investigated. The physical properties such as density, specific heat at constant pressure, ratio of specific heats, acoustic speed, viscosity coefficient and heat transfer coefficient have been considered for various candidate gases from the standpoint of the working fluid for closed cycle gas turbine systems. In the present paper, the influence of Reynolds number has been discussed to investigate the effect of viscosity on compressor performance.

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Oil tankers carrying high viscous oil are usually equipped with the cargo-oil heating system. From the point of view of improvement in economy, the cargo-oil heating system is required to be more efficient. In this paper, comparison of oil heating model testing and 3D unsteady numerical simulation of thermal convection in the tank under the assumption of incompressibility was made to verify numerical calculation method. As the results, it is found that thermal convection performance during model tank heating was approximately characterized by unsteady incompressible thermal convection numerical model.

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This paper described the evaluation of the cooling performance of temperature control system for Agricultural Greenhouse by passing water type heat exchange panel. The temperature control space of this system was made by Styrofoam and heat exchanger panel, and it was installed in the Agricultural Greenhouse. In the theoretical calculation, the temperature in this space was decreasing with increasing thickness of the Styrofoam. However, since the irradiation energy of the sunlight is large, it had been found that it was difficult to keep the room at a low temperature. Moreover, experimental evaluation of this systems was carried out, and found the possibility of temperature control by the ground water.

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Ground source heat exchangers are a growing technology in the area of building air conditioning, and it is therefore important to evaluate soil thermophysical properties at the installation location. We have undertaken such an evaluation at the College of Engineering, Nihon University (Koriyama, Fukushima) using a Thermal Response Test (TRT). The effective thermal conductivity of soil and the thermal resistance of the ground heat exchanger were approximately 2.0 W/(m・K) and 0.086 (m・K)/W respectively. The main component of the soil is sand gravel, and the measured effective thermal conductivity was found to be in agreement with literature values.

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In this study, we investigated temperature and oxygen concentration effects on the phosphorescence of thermographic phosphors which are expected to be applied to two-color phosphor thermometry. For YAG:Pr and BAM:Eu phosphors, two-color ratios showed strong variations with temperature. For YAG:Eu, YAG:Tb, YAG:Ce and YAG:Ce,Tb phosphors, two-color ratios showed so small variations with temperature that those temperature resolutions in the two-color method were quite poor. Furthermore, phosphorescences of YAG:Pr, YAG:Eu and YAG:Ce exhibited insensitivity to oxygen concentration, while those of BAM:Eu, YAG:Tb, and YAG:Ce,Tb exhibited oxygen quenching effect with elevating temperature. However, for BAM:Eu, the two-color ratio exhibited insensitivity to oxygen concentration. The results conclude that YAG:Pr and BAM:Eu phosphors are applicable for phosphor thermometry to domains where oxygen concentration varies.

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LED is more convenient than laser because of its compactness and economical advantage if LED can be used as a light source to the light extinction method. However, whether LED can be an alternative to laser is not verified so far. In this study, soot volume fraction generated in the ethylene jet diffusion flame was measured by light extinction method using both laser and LED as a light source. As a result, the maximum value of the soot volume fraction measured by LED is smaller than that by laser. The peak position of soot generation measured by LED is closer to the center axis of the burner than that by laser.

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Ammonia is regarded as one of the alternative fuels. To use ammonia as the alternative fuel, it is necessary to pay attention to Fuel-NOx formation. In this study, the oxygen-enriched combustion was applied to an NH_3/N_2/O_2 premised flame to make the flame stable. The effects of the oxygen-enriched combustion on characteristics of the NOx formation and on the unburned ammonia remained in the burned gas were evaluated. Results showed that the NO concentration reached to 1.4 % in fuel lean conditions. In fuel rich conditions, the NO concentration decreased with increasing the equivalence ratio.

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Effects of the non-equilibrium plasma superposition on the ammonia / oxygen / nitrogen unburned premixed gas was investigated to improve the laminar burning velocity of the ammonia flame. The plasma-assisted combustion is the one of the methods to improve the combustion characteristics. In this study, the dielectric barrier discharge (DBD) was focused and the effect of the DBD on the burning velocity was experimentally investigated. Results indicated that the burning velocities became faster with increasing the peak to peak voltage of DBD. The largest improvement of the burning velocity was observed at the stoichiometric condition.

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The primary objective of our study is to clarify the effect of alcohol additions on combustion processes of a FAME droplet. Experimental study has been carried out to discuss a statistical characteristics of occurrences of secondary atomization of a burning FAME droplet with methanol additions. Oleic acid methyl ester (OME) is used as FAME of test fuels. It is indicated that the secondary atomization including puffing and micro-explosion occurs in the combustion processes of OME/methanol droplet, and droplet life time is dominated by occurrence of secondary atomization. It is also discussed that effect of exposure time of suspended droplet on changes of internal phase and ratio of micro-explosions.

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The response of a stretched cylindrical diffusion flame to a sinusoidal oscillating air flow was investigated experimentally. The cylindrical flame used in this study had a concave curvature with respect to the fuel stream. The methane diluted with nitrogen was used as fuel. The oscillating frequency of the air flow was varied ranging from 10 to 250 Hz. Following results are obtained: (1) Fluctuating amplitude of the flame curvature decreases with an increase in frequency. (2) Oscillating amplitude of the flame luminosity has a maximum value with respect to the frequency. (3) In a certain frequency range, the variation width of the luminosity of the dynamic flame is larger than that of the static flame in the velocity range corresponding to the fluctuation.

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Jet noise is one of dominant noise sources in an aircraft engine. This paper describes a research on a jet noise reduction device, a chevron nozzle. Although chevron nozzles reduce the jet noise by an effect of promoting the mixing of high velocity jet and external flow, they tend to provide a thrust loss at the same time. In this research, experiments have been conducted using a small turbo-jet engine to evaluate the effect of chevron nozzles on the engine performance from both aspects of noise reduction and thrust loss. Three kinds of chevron shapes and two kinds of nozzle exit geometries have been used in the experiment and results have been compared with the reference nozzle.

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The influence of propelling nozzle exit area on a turbo jet engine performance has been investigated in this paper. The experiments have been conducted for a small turbo jet engine with a standard propelling nozzle and six different nozzles whose nozzle exit areas were varied by ±5%,±10%,±15% from that of the standard nozzle. It has been observed that the running lines on the compressor performance map for enlarged propelling exit areas have been moved away from the surge line, resulting in lowering turbine inlet temperatures and hence specific thrusts as well. On the other hand, the reduction of propelling nozzle exit area has caused the opposite effect for the running lines.

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An influence of the performance degradation of compressor on operating lines of turbo jet engine has been investigated. A model has been developed to estimate the deteriorated centrifugal compressor performance such as pressure ratio and adiabatic efficiency by increasing impeller surface roughness. The modified compressor performance map has been utilized to investigate the effect of performance degradation on running lines of turbo jet engine. The running lines on compressor map have been determined by the matching calculation of components such as compressor, turbine and propelling nozzle. It has been observed that the running lines on the compressor map have been shifted toward surge line, resulting in the loss of thrust and in rising turbine inlet temperatures by increasing blade surface roughness.

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This paper presents a simultaneous imaging method of the temperature and concentration of ethanol aqueous solutions in a microchannel. Absorbance images at the two wavelengths in the ν_2 + ν_3 absorption band of water: 1905 nm and 1935 nm, are simultaneously acquired and converted to the temperature and concentration images. The absorbance at 1905 nm is the most sensitive to the temperature in the band, but that at 1935 nm is insensitive, i.e., an isosbestic point. Whereas, the absorbances at both wavelength are highly sensitive to the water molar fraction, which is inversely proportional to the ethanol concentration. When a 2 wt% ethanol aqueous solution and pure water meet and diffuse to each other, changes in the concentration are observed, and the temperature dependence of the diffusion coefficient is discussed.

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We propose a novel method for estimating three-dimensional temperature distributions of water in a free convection field around a small heated sphere. This method consists of a near-infrared absorption imaging with a wavelength of 1150 nm and inverse Abel transform. Since temperature distributions formed by free convection above a heated sphere can be assumed to be axisymmetric ones, where the axis is in the opposite direction of gravity, the three-dimensional temperature distributions are reconstructed by applying the inverse Abel transform to every absorbance line profile perpendicular to the axis. The reconstructed temperature distributions show the transient process of free convection, indicating the validity of this method.

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Heat transport mechanisms of liquid column oscillated forcedly in a straight channel with square cross section have been investigated experimentally. The channel was initially evacuated, and ethanol was charged to form a liquid column. Vapor pressure, vapor temperature and wall temperature were measured for several oscillation frequencies and several positions of the tip of the liquid column oscillated forcedly. Based on these measurements, vapor mass fluctuations due to phase change were estimated. The effects of oscillation frequency and the position of the tip of liquid column on vapor mass fluctuation are discussed.

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This study experimentally investigated the heat transfer characteristics of oscillating heat pipe (OHP). The OHP was made of copper flat plate, and its flow pattern can be visualization. This OHP had 20 parallel channels. In this study the working fluid was ethanol. The installed condition of the experimental apparatus were performed at horizontal and vertical. As a result, the oscillation frequency of the liquid column increased with the heat input increase, and the effective thermal conductivity is increased. The liquid supply to the heating area a vertical condition was sufficient by gravity. Therefore the maximum effective thermal conductivity of the vertical condition and the horizontal condition was about 15 times and 12.5 times that of copper.

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This paper reports test results and evaluation of a long-distance loop heat pipe (LLHP) with 10 m distances for heat transport. The LLHP could transport heat up to 290 W for 10 m and a thermal resistance between evaporator and condenser was 0.11 K/W. The heat transfer efficiency of the LLHP was discussed more in detail. The results showed that 76.8% of the 240W heat load was dissipated at the condenser line under the condition of no gravitational effect. On the other hand, 73.0% of the 240W heat load was dissipated at the condenser under 30 cm anti-gravitational condition.

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A loop heat pipe (LHP) is heat transfer devices whose operation principle is based on the evaporation and condensation of working fluid, and use the capillary forces to ensure the fluid circulation. In this study, we proposed a new flat evaporator structure and micro LHP with the evaporator thickness of 3mm was designed, fabricated and tested. And we present the three-dimension mathematical model of a flat evaporator of a micro-LHP which takes into account the structural peculiarities of the evaporator and the specific character of a one side heat load supply. The computational results from the mathematical model were compared with experimental data; there was good agreement between predicted and measured temperature distributions.

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We, the outer breathing through a single channel gas intermittently in both directions, were tested in order to obtain the basic knowledge to adapt the total heat exchange technology, "intermittent small heat exchanger module "We aim the establishment of the analysis method. This time, we developed a simple evaluation test unit the total heat exchange performance and pressure loss of the "intermittent small total heat exchange module", the components of the "intermittent small heat exchanger module," the interior of the adsorbent that we have prototyped and it is reported due to the difference in impregnation amount has performed comparative experiments of total heat exchange efficiency and pressure loss.

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The function of the magnetocaloric heat pump with an active magnetic regenerator (AMR) cycle is based on the magnetocaloric effect (MCE) of a magnetocaloric material (MCM). Because the range within which the MCM exhibits an MCE is narrow near its Curie point, an AMR system with material layers, based on the arrangement of a couple of MCMs in the regenerator is needed. In order to estimate the influence of the packed number of MCMs, the refrigeration capacity and the generated temperature span of the magnetocaloric heat pump using the material-layered AMR are numerically evaluated in this study.

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A ground source heat pump (GSHP) is paying attention as one of the energy saving technologies. The purpose of this study is to investigate a heat exchanging performance of a ground source heat pump using direct expansion method. The direct expansion method for heat exchange will be more efficient comparing with the conventional indirect heat exchange method. However it is difficult to measure the calorimetric value of the heat pump system using direct expansion method because the refrigerant becomes two phase flow. Therefore, we evaluated the calorimetric value around the indoor unit of the heat pump system. We also improved the accuracy of the measurement of the velocity distribution using the traversing system of the hot wire anemometer.

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This paper describes a transient model of a loop heat pipe (LHP) based on a mass-spring-damper system, and its verification with an experimental result. The model is based on the one-dimensional and time dependent conservation equations. The momentum equation and energy equation were solved in the model. Mass-spring-damper system was also solved to calculate the two-phase length. The calculation results were compared with the experimental results of a LHP with PTFE wick and ethanol as a working fluid. The calculated result had the good agreement with the experimental result.

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