掲載種別：研究論文（学術雑誌）  

The natural convective heat transfer from a heated horizontal disc with gapped heated hollow cylinders was investigated experimentally, forming the foundation for improving the cooling performance of the heat sinks. The cooling target for this study was the central area of the heated horizontal disc where the heat dissipation was low. The heat transfer was greatly enhanced by the reversal of the flow from the gap between the heated hollow cylinders towards the heated horizontal disc. The reverse flow was promoted by the conditions of a narrow clearance between the heated horizontal disc and the heated hollow cylinder and a wide gap between the heated hollow cylinders. Conversely, for the flow along the heated horizontal disc, the heat transfer showed improvement by increasing the clearance between the heated horizontal disc and the heated hollow cylinder. The relationship between the heat transfer and flow properties was demonstrated using the Nusselt number of the heated horizontal disc and the Rayleigh number corrected for the ratio of the heated hollow cylinder height to the clearance between the heated horizontal disc and the heated hollow cylinder.

DOI： 10.1016/j.icheatmasstransfer.2023.106928

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掲載種別：研究論文（学術雑誌）  

Microencapsulation of n-tetracosane, whose melting point is approximately 50 °C, in a silica shell has been performed through the sol–gel method using tetraethyl orthosilicate (TEOS) as the precursor for silica-shell formation. Additionally, two types of silane coupling agents were used to modify the surface of the microcapsules to change the wettability. The morphology of the microcapsules was observed by scanning electron microscopy. The chemical composition was characterized by Fourier transform infrared spectroscopy. The results confirmed the presence of n-tetracosane and silica in the synthesized microcapsules. Wettability analysis showed hydrophobic and hydrophilic features because of the added silane coupling agents. From the results of differential scanning calorimetry measurements, the encapsulation ratio of the microcapsules increased with decreasing TEOS/n-tetracosane ratio, and the highest encapsulation ratio was 87.1 % at a TEOS/n-tetracosane ratio of 0.25. The pH in the microcapsule solution was affected by addition of a silane coupling agent, and shifting the pH to the basic side lowered the encapsulation ratio owing to enhancement of silica condensation. After 100 differential scanning calorimetry cycles, there was no significant degradation in the phase-change temperatures and enthalpies, which confirmed the good phase-change stability and repeatability. Therefore, the microcapsules are a potential material for thermal-energy-storage systems to effectively utilize energy.

DOI： 10.1007/s10765-023-03179-1

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掲載種別：研究論文（学術雑誌）  

Microencapsulated n-tetracosane as a phase change material with an inorganic calcium carbonate (CaCO3) shell has been synthesized through a self-assembly process with varying pH value of a precursor solution, and the resultant materials were systematically investigated. Spherical microcapsules with a mean diameter of less than 3 μm were seen by microscopic observation. X-ray diffraction analysis revealed the presence of three CaCO3 polymorphs such as calcite, aragonite, and vaterite in the shell, and these compositions depended on the solution pH. This fact was also confirmed by Fourier transform infrared spectra and reflected in the surface morphology of microcapsules. The characterization of the phase change behavior has shown no significant change in the phase change temperatures and more than 170 mJ/mg of phase change enthalpies with the microcapsules synthesized at pH = 1. This enthalpy corresponds to 69.2% of encapsulation efficiency which is improved from the value reported by other microcapsules with CaCO3 shells. Thermal cycling analysis exhibited good reliability and durability of phase change phenomena in the long term. These results demonstrate a promising potential of microcapsules for developing thermal energy storage materials at a mild temperature range, which can be applied for waste heat recovery applications.

DOI： 10.1021/acs.energyfuels.2c03564

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担当区分：責任著者   掲載種別：研究論文（学術雑誌）  

A spraying system was constructed with a microencapsulated phase change material (MPCM) slurry as the working medium to weaken the adverse effects of the slurry's high viscosity and low thermal conductivity on heat transfer in a wall tube heat exchanger. The temperature distributions of pure water and MPCM slurry were first obtained through infrared thermal imaging in spraying. Furthermore, the latent heat use of MPCM slurry was investigated through a new method based on the temperature properties of the phase change fluid, in which the working and phase change temperature ranges are matched. The heat-mass transfer characteristics are compared and discussed with those of the base fluid, and the latent heat use of 10wt% MPCM slurry containing the core material n-docosane (C22H46). The experimental results indicate that the phase change enables the MPCM slurry droplets to maintain a higher temperature than a fluid with no phase change or base fluid. Different application modes (static and spraying) have correspondingly different phase change temperature ranges owing to supercooling, and the degree of matching between the working and phase change temperature ranges has a critical impact on the latent heat use of the MPCM slurry. Finally, comparing the heat transfer coefficients and Lewis numbers between the base liquid and MPCM slurry reveals that the phase change not only enhances the heat transfer but also slightly reduces water evaporation compared with pure water spraying.

DOI： 10.1016/j.ijheatmasstransfer.2022.123573

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掲載種別：研究論文（学術雑誌）  

Droplet transportation using a wettability gradient surface has attracted much attention owing to applications such as in microfluidic devices. A surface with a spatial structural gradient was prepared through a simple and cost-effective process even though understanding of droplet behavior on the structure was still limited. Here, we report impinging droplet motion on a gradient wrinkled surface. Surfaces were prepared through hard film deposition on soft pre-strained polydimethylsiloxane (PDMS) with a mask installed with a slit to control the amount of deposition, which is related to the wavelength of the wrinkles. Droplets were impinged with varying position with respect to the structure, and the droplet motion was observed in the direction away from the region under the slit. We found an asymmetric contact angle and alternate motion on both sides of the three-phase contact line during the motion according to the gradient of the wrinkle wavelength. These results may help not only to understand the behavior of droplet impingement on a gradient structural surface but also to further develop applications using directional droplet transfer.

DOI： 10.1039/d1ra09244h

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

DOI： 10.1007/s10765-022-02996-0

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その他リンク： https://link.springer.com/article/10.1007/s10765-022-02996-0/fulltext.html

掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Science and Business Media LLC  

DOI： 10.1007/s10765-021-02944-4

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その他リンク： https://link.springer.com/article/10.1007/s10765-021-02944-4/fulltext.html

担当区分：最終著者   掲載種別：研究論文（学術雑誌）  

Microencapsulated phase change material (MPCM) slurries are energy-carrier fluids. Their latent heat utilization has been investigated by a new method based on the temperature properties of the phase-change fluid, in which match of the working and phase-change temperature ranges is considered. Based on the working-temperature range (3–15 °C) in heat-exchange circulation, the dynamic heat-transfer characteristics and utilization of the MPCM slurry with the core material n-docosane (C22H46) are discussed. The experimental results indicate that the effects of the stirring rate and flow rate on the dynamic heat-transfer characteristics are similar to those of water, and they have little influence on utilization of the 10% MPCM slurry, whereas the corresponding effect of the concentration is relatively large. When investigating the effect of the concentration, it was found that a low phase-change ratio suppressed movement of the phase-change-temperature range owing to the residual solid core material acting as a crystal nucleus, while the heat-transfer performance and latent heat utilization of the MPCM slurry suppressed each other. The 10% MPCM slurry is the most suitable energy carrier fluid, but supercooling still needs to be resolved. The experimental results provide a reference for practical efficient application of MPCM slurries as energy carrier fluids.

DOI： 10.1016/j.icheatmasstransfer.2021.105788

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記述言語：日本語   出版者・発行元：社団法人 日本伝熱学会  

DOI： 10.11368/tse.30.23

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Thermophysical Properties  

DOI： 10.2963/jjtp.35.76

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2020.115512

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掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Thermophysical Properties  

DOI： 10.2963/jjtp.34.147

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掲載種別：研究論文（国際会議プロシーディングス）  

This paper deals with the characteristics of a straight pipe inner flow of the nanosuspension that has non-Newtonian viscosity. The parameters are set in the mass composition of 10–20 mass% of dispersoid and in the temperature range of 20–70 ℃ that includes the melting point of tetracosane. The experimental study is carried out by using the flow pressure loss measurement apparatus. The test section that made of a stainless straight pipe has an inner diameter 8 mm, and it has the length 1000 mm. The inner flow of a straight pipe is occurred by using a pump that is controlled by an inverter. The pressure drop is measured by a differential pressure gauge. The measured pressure loss is used for the calculation of the flow friction loss coefficient and the pump power. The experimental data are evaluated by the variation of the pressure loss coefficient with Reynolds number that defined by the non-Newtonian behavior. Viscosity data by previous study data that correlated by the power law method are used for Reynolds number calculation. The viscosity including non-Newtonian characteristics had been estimated by using a rotary viscosity meter. The measuring ranges are shear rate <500 1/s and temperature 10–84 ℃. The calculation data from experimental correlation equation, which was adjusted by an exponential law, are used for Reynold’s number. The flow friction loss coefficient and the pump power are estimated by measured flow pressure loss. The heat transport amount is calculated by the sensible heat and the latent heat of nanosuspension. The thermal property data (specific heat and latent heat) are the obtained data by previous study that measured by using differential scanning calorimeter. The relationship between the heat transport amount and pump power of this study is shown that the heat transport ability of nanosuspension is 1.5–2 times of water at the same value of pump power.

DOI： 10.1007/978-981-15-1892-8_2

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.langmuir.9b01173

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Thermophysical Properties  

DOI： 10.2963/jjtp.33.151

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.icheatmasstransfer.2018.08.021

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.8b06406

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1615/ihtc16.bae.022231

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1615/ihtc16.cov.021496

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1103/PhysRevE.97.043113

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-017-2108-2

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11368/tse.26.19

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s10765-017-2238-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2963/jjtp.31.125

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掲載種別：研究論文（学術雑誌）  

DOI： 10.2963/jjtp.31.118

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-016-1767-8

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11630-016-0898-z

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2963/jjtp.30.80

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記述言語：日本語   出版者・発行元：日本熱物性学会  

<p>本研究は，廃食油を再利用する事が可能なボイラ燃料の開発を最終目標として，重油又は灯油と食用油の混合連続相中に微小水滴を分散させたW/Oエマルション燃料の熱物性値を測定評価した結果を示すものである．この種の燃料は，燃焼過程において分散液適のミクロ燃焼が二次微粒化作用と燃焼促進作用をもたらすことが知られている．本報は，従来の灯油または重油に替えて食用油混合W/Oエマルション燃料を使用する際に必要となる，発熱量および粘性特性を測定した評価結果を示すものである．測定された発熱量は，加成性法則による評価が行われ，同法による推算が可能であることを示す．粘性は，組成質量割合によっては非ニュートン性が観察され，べき乗則による実験整理式を提示する．</p>

DOI： 10.2963/jjtp.30.80

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2014.11.050

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PERGAMON-ELSEVIER SCIENCE LTD  

Recently, latent heat thermal energy storage system has gained attentions in order to utilize the middle temperature factory waste heat (100-200 degrees C). The purpose of this study is to develop heat storage system with a latent heat storage material for using the middle temperature heat. In this study, the direct contact melting and solidification behavior between heat transfer fluid (oil) and erythritol (PCM) were visualized in order to investigate the characteristics of heat storage and release at difference flow rate of oil (1.0-4.0 kg/min) and the effects of perforated partition plate. In this direct contact method, if the packed height of erythritol increases due to porous solidification, erythritol may be flowed out from a vessel with oil. So to control the packed erythritol height, the effect of a perforated partition plate in the vessel was investigated. As a result, it is found that since the bubbles of PCM are broken by the perforated partition plate, it prevents that the solidified height of PCM increases. (C) 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.ijheatmasstransfer.2014.11.050

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1615/JPorMedia.2015012375

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1615/JPorMedia.2015012156

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記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Mechanical Engineers  

The effects of design parameters on natural convection heat transfer from a horizontal heated surface with a heated cylindrical pipe were estimated experimentally. The parameters considered were the heat flux of the horizontal heater and the aspect ratio of the heated cylinder. The flow fields around the horizontal heated surface and the heated cylinder were visualized. The results showed that flow characteristics have three distinctive patterns: non flow reversal, flow reversal occurred only in the heated cylinder and reached to the horizontal heater. The necessary conditions to determine the flow fields were discussed. With decreasing the distance of between the heaters and the aspect ratio of the heated cylinder, the ascending flow velocity in the pipe becomes low and flow reversal occurs. In all flow fields, an increasing in the heat flux of the horizontal heater enhances the heat transfer. In the case of no flow reversal and flow reversal occurred only in the heated cylinder, the heat transfer shows the same tendency and increases with increasing the aspect ratio of the heated cylinder. On the other hand, when flow reversal reaches to the horizontal heater, the heat transfer has a little influence on the heated cylinder conditions. Nusselt number is expressed as a function of the modified Rayleigh number of heaters and the nondimensional height.

DOI： 10.1299/transjsme.14-00400

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11368/tse.23.5

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Recently, metal fiber materials were made by laminating metal fibers with a diameter of about 30 μm to 300 μm. Since the almost metal fibers were oriented in the horizontal direction (the major axis of the fiber), these metal fiber materials are estimated to be anisotropic with an effective thermal conductivity. However, there is little quantitative data on the anisotropic effective thermal conductivity of the various kinds of metal fiber materials. The purpose of this study is to investigate the anisotropic effective thermal conductivity of various metal fiber materials experimentally and theoretically. In order to measure the horizontal and vertical effective thermal conductivities of these metal fiber materials, new measurement devices were developed. As a result, it is found that the anisotropic effective thermal conductivity of the various metal fiber materials was confirmed, and the horizontal and vertical effective thermal conductivities of these metal fiber materials depend on the bulk density or porosity, Young's modulus, the fiber length, and fiber diameter. And a dimensionless correlation equation for predicting the vertical and horizontal effective thermal conductivities of the various kinds of metal fiber materials was derived in terms of various dimensionless parameters. © 2011 Springer Science+Business Media, LLC.

DOI： 10.1007/s10765-011-1066-z

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2013.06.055

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2013.02.010

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s11630-013-0605-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.4236/ojfd.2013.32A008

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.79.2289

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Heat Transfer Society of Japan  

Recently, latent heat thermal energy storage system has been used in order to utilize the middle-temperature (100 - 200 °C ) factory-waste heat. In the range of middle temperature, erythritol is a suitable PCM, which has melting point at 119 °C , and latent heat of 340 kJ ⁄ kg . In this experiment, silicon oil as a heat transfer fluid injects from the nozzle plate of the bottom of a heat storage vessel. It flows to the upper direction through PCM region and heat is directly transfered between PCM and oil. In this study, the melting and solidification behavior between oil and PCM were visualized in order to investigate the characteristics of heat storage and release at difference flow rate of heat transfer fluid (1.0 - 4.0 kg ⁄ min ) and packed height of PCM (0.23, 0.45, 0.60 m ). The experimental result shows that the amount of heat storage and release is influenced by the flow rate of oil and the packed height of PCM. It is found that the volumetric overall heat transfer coefficient increases when the flow rate of the oil increases. During solidification process, the volumetric overall heat transfer coefficient decreases with increasing the packed height of PCM, while, it is not different in the melting process.

DOI： 10.11368/tse.21.83

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10024835298?from=CiNii

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijheatmasstransfer.2012.07.021

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記述言語：日本語   出版者・発行元：The Heat Transfer Society of Japan  

The purpose of this study is to understand the factor that influenced the heating efficiency of the outward and inward multi-hole gas burner. The flame-hole angle and the distance from flame hole to heating object are chosen as the experimental parameter. The measurement of the flame temperature distribution is carried out on each experimental condition. LPG (Liquefied petroleum gas) is used for the test fuel gas. The compositions of LPG are propane 97.5vol%, butane 0.2vol% and methane + ethylene 2.3vol%. It is clarified that the optimum ranges of the flame-hole angle and the distance from flame hole to heating object. The experimental correlation equation is proposed for the outward and inward multi-flame-hole gas burner by design factors.

DOI： 10.11368/tse.20.51

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記述言語：日本語   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

The purpose of this study is to examine the dehumidification behavior of a block type desiccant unit of organic sorbent. This unit has simple rectangular parallelepiped shape, and initial cost can be lower than the desiccant rotor. This unit will be used in batch system that one unit is used for sorption and another is used for desorption at the same time. Experimental conditions are as follows, sorption air temperature is 18 °C, sorption air relative humidity is 90%, desorption air temperature is 40°C, and desorption air relative humidity is 36%. It was found that completed time of desorption is earlier than that of sorption. As a result, sorption and desorption characteristics of the block type sorbent unit and their overall-mass-transfer coefficients are clarified.

DOI： 10.11322/tjsrae.29.153

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10003897682?from=CiNii

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

In order to improve the sorption efficiency of the desiccant rotor, double ventilation rotor system has been proposed. In this system, at first the process air is dehumidified in the rotor. Next, the air becomes high relative humidity by cooling with an evaporator, and it is ventilated to the rotor again. In the first report, ventilation experiments of four types of air flow routes were investigated and it is clarified that each route has own characteristics on dehumidification. In this paper, the experiments of double ventilation rotor system of various flow routes were investigated with a refrigerator as a heat pump. Temperature and absolute humidity of the air at the entrance and exit of each zone were measured. Dehumidification amount of the rotor in single ventilation dehumidification system was equal to that in double ventilation dehumidification system. But recovered cold heat from evaporator in double ventilation dehumidification system was higher than that in single ventilation dehumidification system. With increasing the absolute humidity of inlet air, dehumidification amount of the rotor in each route and the absolute humidity of exit air increased. The COP of double ventilation dehumidification system was higher than that of single ventilation dehumidification system.

DOI： 10.11322/tjsrae.29.131

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10003897668?from=CiNii

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jtst.7.563

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記述言語：日本語   出版者・発行元：Japan Society of Refrigerating and Air Conditioning Engineers  

In this paper, the desiccant rotor with double ventilation system is proposed in order to improve the sorption efficiency of the rotor. In this system, the processing air is dehumidified with the rotor. Next, the air becomes high relative humidity by cooling with an air cooler, and it is ventilated to the rotor again for dehumidification. This desiccant rotor with the organic sorbent has high adsorption ability at high relative humidity and can be recovered at low temperature. In this study, ventilation experiments of four types of air flow routes were investigated. In the experiment, temperature and absolute humidity of the air at the entrance and exit of each zone were measured. It is clarified that each route has own characteristics on dehumidification. As a result, it is found the most suitable route of the double ventilation dehumidification system.

DOI： 10.11322/tjsrae.29.119

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10003897651?from=CiNii

担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.77.1801

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOCIETY OF THERMOPHYSICAL PROPERTIES  

本研究では，工場から出る100℃〜250℃の中間温度域の廃熱を利用するため，潜熱蓄熱システムで利用可能な相変化物質としてエリスリトールとマンニトール，およびこれらの混合物の基礎的融解特性に関する実験を行った．エリスリトールとマンニトールの融点，混合物の融解ピーク温度および潜熱量をDSCで測定し，さらに試験管に入れた試料の融解挙動をデジタルカメラで観察した．その結果1)混合物のマンニトール含有量が10〜40mass%と50〜65mass%，および70〜90mass%の時にそれぞれ1ヶ所，3ヶ所，2ヶ所の融解ピーク温度が現れることを確認した．2)混合物の基礎的融解挙動観察では，凝固融解の繰り返しによって挙動が変化しないこと，固相と液相の密度差が融解挙動に影響を与えることを確認した．

DOI： 10.2963/jjtp.25.136

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20008145824?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：HINDAWI PUBLISHING CORPORATION  

Flow drag and heat transfer reduction effects are useful in heat energy transportation systems and can lead to lower pumping energy requirements. The purpose of this research is to describe the flow drag and heat transfer reduction characteristics of organic (potassium acetate) and inorganic (calcium chloride) brine solutions. The nonionic surfactant oleyl dihydroxyethyl amine oxide (ODEAO) is used as a drag-reducing additive. The pipe friction coefficient and heat transfer coefficient are investigated experimentally in a straight pipe for each type of solution with ODEAO. These coefficients are found to be lower than those of water in the turbulent flow range. However, the rod-like micelles of ODEAO, which are necessary to induce the flow drag reduction effect, are not readily formed in these solutions. Hence, the flow drag and heat transfer reduction effects are measured only under limited conditions and it is difficult to apply these solutions practically as heat transfer media.

DOI： 10.1155/2011/206219

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担当区分：筆頭著者   記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.76.764_625

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DOI： 10.11322/tjsrae.26.173

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DOI： 10.11322/tjsrae.26.489

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/08916150903099173

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.2970076

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-008-0371-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jtst.3.195

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jtst.3.207

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-006-0121-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/htj.20134

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.2217751

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.2227043

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jtst.1.66

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

DOI： 10.11322/tjsrae.23.479

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-004-0599-0

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.ijrefrig.2004.07.012

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記述言語：日本語   出版者・発行元：JAPAN SOCIETY OF THERMOPHYSICAL PROPERTIES  

現在，低温用の２次冷媒として使用されている有機系ブラインに対して流動抵抗低減効果を適用した搬送エネルギーの削減技術が注目されている．しかしながら，流動抵抗低減剤である界面活性剤が添加された有機系ブラインの粘度は非ニュートン特性やSIS（Shear Induced State）状態などの特異な粘度を示すため，実用化のためには，粘度の把握が必要不可欠である．本研究では，回転式レオメーターによって界面活性剤添加有機系ブラインの粘度測定を行ってその特異な粘度を明らかにし，さらに，実用化を想定した流動抵抗および熱伝達実験に対して適用可能な粘度の無次元整理法の検討を行い，流動抵抗および熱伝達実験結果への実際の適用結果を示した．

DOI： 10.2963/jjtp.19.67

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00251431431?from=CiNii

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.71.573

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-004-0512-x

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.1773584

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER-VERLAG  

This paper has dealt with the natural convection heat transfer characteristics of microemulsion slurry composed of water, fine particles of phase change material (PCM) in rectangular enclosures. The microemulsion slurry exhibited non-Newtonian pseudoplastic fluid behavior, and the phase changing process can show dramatically variations in both thermophysical and rheological properties with temperature. The experiments have been carried out separately in three subdivided regions in which the state of PCM in microemulsion is in only solid phase, two phases (coexistence of solid and liquid phases) or only liquid phase. The complicated heat transfer characteristics of natural convection have appeared in the phase changing region. The phase change phenomenon of the PCM enhanced the heat transfer in natural convection, and the Nusselt number was generalized by introducing a modified Stefan number. However, the Nusselt number did not show a linear output with the height of the enclosure, since a top conduction lid or stagnant layer was induced over a certain height of the enclosure. The Nusselt number increased with a decrease in aspect ratio (width/height of the rectangular enclosure) even including the side-wall effect. However, the microemulsion was more viscous while the PCM was in the solid phase, the side-wall effect on heat transfer was greater for the PCM in the solid region than that for the PCM in the liquid region. The correlation generalized for the PCM in a single phase is Nu=1/3(1-C-1)Ra-1/3,Ra-5n+1, where C1=e(-0.09AR) for the PCM in solid phase and C-1 = e(-0.33AR) for the PCM in liquid phase. For the PCM in the phase changing region, the correlation can be expressed as Nu=CRa(1/7n+2)Ste(-(1.9-1.65n)), where C = 1.22 - 0.035AR for AR&gt;10 and C=0.55-16.4e(-1.1AR) for AR&lt;10. The enclosure height used in the present experiments was varied from H=5.5 [mm] to 30.4 [mm] at the fixed width W=120 [mm] and depth D=120 [mm]. The experiments were done in the range of modified Rayleigh number 7.0x10(2)less than or equal toRaless than or equal to3.0x10(6), while the enclosure aspect ratio AR varied from 3.9 to 21.8.

DOI： 10.1007/s00231-003-0419-y

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN SOC MECHANICAL ENGINEERS  

In the present experimental study, the stability of Rayleigh-Bernard convection has been investigated in rectangular enclosures filled with microemulsion Phase-Change-Material (PCM) slurry. The PCM slurry exhibited a pseudoplastic non-Newtonian fluid behavior. Hysteresis in convection was clearly observed while the PCM were in a solid phase and in phase changing. The critical Rayleigh number decreases with the PCM mass concentration while the PCM is in phase changing. The fluid temperature at the center of the enclosure showed a time-dependent oscillation during the transition from a heat conduction state to a convection state. The maximum Nusselt number has been observed for all of the slurries while the heating plate was controlled at a temperature that most of PCM was in phase changing.

DOI： 10.1299/jsmeb.47.126

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.70.444

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.70.209

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DOI： 10.11322/tjsrae.21.33

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0017-9310(03)00289-8

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S1290-0729(02)00048-0

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s00231-002-0298-7

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.69.2486

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.69.2122

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記述言語：日本語   出版者・発行元：公益社団法人 空気調和・衛生工学会  

本研究は,高圧水の高い空気溶解性を利用し,その減圧操作により水中で微細気泡生成を試みたものである.実験因子として水圧力,水温度,減圧ノズル直径などを選び,これら諸因子の生成気泡径に及ぼす影響を実験的に検討した.減圧により飽和状態から過飽和状態へと変えて気泡を発生させる場合において,気泡核から気泡へと成長する過程で水の粘性が大きく影響し,加圧溶解時の濃度と大気圧下での濃度の比を高くし,シュミット数を大きくすれば気泡直径が減少することを把握した.最終的に微細気泡生成に関する諸因子の無次元数の定義とその無次元整理式の誘導を行った.

DOI： 10.18948/shase.28.90_1

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記述言語：日本語   出版者・発行元：空気調和・衛生工学会  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

DOI： 10.11322/tjsrae.20.37

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s002310100200

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jsmeb.45.322

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jsmeb.45.183

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.68.2606

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.68.1537

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.68.481

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.68.161

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

DOI： 10.11322/tjsrae.19.13

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

DOI： 10.11322/tjsrae.19.151

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

It was clarified that the transportation of latent heat evolved by melting and solidifying the latent heat microcapsules. Exerted on strong influence on the natural convection heat transfer in the latent microcapsule layer. The numerical results revealed quantitatively that the natural convection heat transfer depended on the concentration of microcapsule slurry, temperature difference between the heating and cooling walls, and width of the rectangular cavity.

DOI： 10.1299/jsmeptec.2002.0_219

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jsmeb.44.328

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.67.2113

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.67.2105

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記述言語：英語  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Brine flow characteristics with drag reduction surfactant are important to reduce energy consumption in a pipeline system. Oleyldihydroxyetyl Arhine Oxide (ODEAO) reported as an effective drag reduction surfactant additive was add to Ethylene Glycol (EG) solution at 40wt% as the brine in the present study. The friction factor and heat transfer coefficient of the Ethylene' Glycol solution with ODEAO were measured as a function of various solution temperatures. It was found that the solution temperature has exerted an influence on the flow drag and heat transfer reduction rate of the EG solution with the ODEAO surfactant.

DOI： 10.1299/jsmeptec.2001.0_13

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

The objective of the present study is to investigate the advanced thermal energy storage/transport system with ice water slurry. Thermal energy storage systems for air conditioning has been developed actively for the purpose of saving energy and reducing the peak electrical demand in the daytime during summer. In particular, a great deal of attention has been paid to the thermal energy storage system with ice water slurry since it would be beneficial to be able to utilize the large latent heat of melting ice. It is required to clarify fundamental making/transport/melting mechanism of ice water slurry for the systems, so this paper deals with a dynamic ice making characteristics using flowing supercooled water solutions, pressure drop of flowing ice water slurry in a pipe, and melting heat transfer of ice water slurry in a heat exchanger.

DOI： 10.1299/jsmeptec.2001.0_207

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Abstracts A two-dimensional numerical study has been conducted to obtain fluid flow and heat transfer characteristics of Rayleigh-Benard natural convection in non-Newtonian Phase-Change-Material (PCM) slurries inside a rectangular enclosure with isothermal horizontal hot and cold plates and adiabatic side walls. Generally, a PCM slurry has the properties that its density draws down sharply but continuously with the melting of PCM and its specific heat capacity shows a peak value during melting. Some PCM slurries such as microemulsions can exhibit pseudoplastic non-Newtonian fluid behavior. This paper deals with the differences in natural convection and flow patterns between Newtonian and non-Newtonian fluids of which with or without PCM theoretically. Given in the paper are also some explanations and mechanisms about the results. The simulation is performed with the following parameters: a shear thinning pseudoplastic fluid for 0.8&le;n&le;1.0, Ra&le;2×10^6, Pr=70〜210, and the aspect ratio from 1:5 to 1:20.

DOI： 10.1299/jsmeptec.2001.0_171

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In order to use fluidity characteristics of ice slurry, it is neccesary to prevent ice particles.from adhering a cooling surface and agglomeration of ice particles. The purpose of this study is to observe ice particle characteristics of propylene glycol water solution added with an antiagglomeration surfactant. The results revealed that the fluidity characteristics of ice particles were made by the surfactant in comparison with the solution without the surfactant.

DOI： 10.1299/jsmeptec.2001.0_477

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

The present study deals with the characteristics of the heat storage vessel packed with rectangular phase change materials by numerical analysis. The latent heat storage materials in the vessel are heated by utilizing the natural convection of the heat transfer medium, which flow the interval of the latent heat storage materials. The interval of rectangular latent heat storage materials is greatly related to natural convection of the heat transfer medium. Numerical results revealed temperature profiles and flow patterns of the heat transfer medium affected the heat storage characteristics.

DOI： 10.1299/jsmeptec.2001.0_487

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s002310050382

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.1286333

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/jsmeb.43.52

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S1290-0729(00)00200-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：HEMISPHERE PUBL CORP  

The effects of various parameters on the limiting characteristics of an open-type water-cooled flat-plate collector were studied numerically. The results showed that the heat and mass transfer was enhanced with an increase in the inlet water temperature. The operating temperature and the interfacial mass flux maintained a higher constant for 4 and 2 hours around the noontime, respectively. An increase in atmospheric temperature or humidity and a decrease in the film thickness caused the operating temperature to rise to some extent. The wind velocity exerted a great influence on the operating temperature.

DOI： 10.1080/104077800274415

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記述言語：日本語   出版者・発行元：公益社団法人 空気調和・衛生工学会  

本論文は,温水層とその底部に設けた金網を介して吹き込まれる空気泡群との間の直接接触による熱及び物質交換特性に及ぼす諸因子の効果について実験的な検討を行ったものである.その結果,温水層内へ流入する空塔空気流速の増加に伴って,発生する空気泡群の流動状態は独立空気泡領域,遷移領域,空気泡合体成長領域へと変化し,空気泡群と温水との間の熱・物質交換は,空塔流速の増加と共に,その熱伝達および物質伝達の増加割合が変化することを定量的に明らかにした.最終的に,空気泡群と温水間の熱伝達と物質伝達に関する無次元整理式の誘導を行った.

DOI： 10.18948/shase.25.79_71

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.66.650_2661

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DOI： 10.11322/tjsrae.17.343

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DOI： 10.11322/tjsrae.17.333

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.66.647_1818

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.66.652_3204

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.66.651_2964

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

DOI： 10.11322/tjsrae.17.159

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.66.1487

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0035-3159(99)80028-2

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER VERLAG  

This paper has concerned the heat and mass transfer of a water film falling down a tilted plate with radiant heating and water evaporation. A cluster of physical models was developed for evaluating the properties of heat and mass transfer. A fully implicit control-volume finite-difference procedure was used to solve the coupling equations. The effects of various parameters on heat and mass transfer were investigated. The results showed that the mass fraction of water vapor in ambient atmosphere and the flow turbulence played key roles in the heat and mass transfer. The ambient atmospheric temperature dramatically affected the sensible heat flux. However its effect on the latent heat flux is negligibly small. The magnitude of solar incident flux had an intense influence on the water film temperature.

DOI： 10.1007/s002310050274

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記述言語：日本語   出版者・発行元：社団法人日本機械学会  

Transient heat release characteristics of a latent heat storage vessel packed with surface cross-linked form stabilized high-density polyethylene pellets as a phase change material (PCM) have been investigated numerically and experimentally. The obtained results revealed the effects of the inlet velocity, the inlet temperature of ethylene glycol/water solution as a heat transfer medium, and the amount of the PCM on the heat release characteristics. As a result, the nondimensional correlation equation of the completion time of the heat release process was derived as a function of some nondimensional parameters.エネルギーの効率的変換及び熱エネルギーの有効利用の立場から、著者らは脱カプセル型の表面架橋を施した形状安定化潜熱蓄熱材の開発とその蓄熱槽内での蓄放熱特性をそれぞれ実験及び数値計算により解明し、その優れた蓄放熱特性を明らかにした。さらに、前報では、中温度水準（130～150℃）の潜熱蓄熱材として表面架橋処理を施した形状安定化ポリエチレンペレット（以下粒状蓄熱材と呼ぶ）に着目し、粒状蓄熱材と熱媒体としてのエチレングリコール水溶液（以下熱媒体と呼ぶ）を充填した新たな潜熱蓄熱槽を提案した。すなわち、その蓄熱槽下部に設けた電気ヒーターの加熱により、蓄熱槽内の熱媒体の沸騰そしてその凝縮現象に伴う大きな凝縮熱により、粒状蓄熱材を急速に融解蓄熱した場合の蓄熱性を諸因子のもとで解明した。本報告は、前報の粒状蓄熱材を融解蓄熱した蓄熱槽からの熱抽出、すなわち融解した粒状蓄熱材の凝固に伴う放熱特性を実験及び数値計算により解明し、この種の新しいタイプの潜熱蓄熱システムの特徴を明らかにするものである。まず、放熱実験結果に基づいた数値計算モデルを提案し、その放熱特性に影響を及ぼす熱媒体の入口流速、熱媒体の入り口温度及び粒状蓄熱材の充填高さ等の効果を実験と数値計算により総合的に検討するものである。特に、得られた結果をもとに、この種の潜熱蓄熱槽の放熱完了時間に関する無次元整理式の誘導も試みてある。

DOI： 10.1299/kikaib.65.973

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その他リンク： http://ousar.lib.okayama-u.ac.jp/11189

記述言語：英語   出版者・発行元：The Japanese Society of Snow and Ice  

本論文は,傾斜した屋根上への積雪防止に流下水膜を利用した場合の研究成果を述べたものである.水膜を乱流とし,その上の降雪を含む大気を,0℃以下の飽和蒸気の層流として数値解析した解析モデルを誘導した.様々な因子の熱伝達や水膜温度降下に及ぼす効果が研究された.その結果,傾斜した屋根上の積雪防止に流下水膜を用いることが有効であることを解明した.水膜温度降下,水量,屋根の長さや傾斜角そして降雪強さ,大気温度および風速が融雪に重要な役割を及ぼすことを定量的に明らかにした.これらの諸因子の屋根上積雪防止に関する限界条件を見い出した.さらに,水膜の熱伝達に関する無次元整理式の誘導にも成功した.

DOI： 10.5331/seppyo.61.445

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00067773343?from=CiNii

記述言語：日本語   出版者・発行元：公益社団法人 日本冷凍空調学会  

This paper has dealt with liquid-liquid direct contact heat transfer characteristics by means of water insoluble heat transfer medium. In the present study, Perfluorocarbon(PFC, density of 1830kg/m³)was injected from above into a hot water layer, which was mounted by stainless steel wire net in order to make PFC droplets finer. The measuring result of the drop let diameter revealed that the droplet size distribution exerted an influence on the temperature effectiveness between PFC droplets and the hot water layer. It was observed that PFC droplets were dispersed by collision with stainless steel wire nets during falling in the hot water layer. Finally correlations equations of the temperature effectiveness and average diameter of PFC droplets had been derived as a function of some parameters.

DOI： 10.11322/tjsrae.16.167

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.65.3777

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1299/kikaib.65.2454

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記述言語：日本語   出版者・発行元：公益社団法人 空気調和・衛生工学会  

本研究は,暖房用空気熱媒体の昇温熱源として,マイクロカプセル化したパラフィン系潜熱蓄熱材の混合水を充てんした潜熱蓄熱槽を提案し,その蓄熱槽に熱媒体としての低温空気泡群を噴射した場合の放熱特性に影響を及ぼす諸因子の効果を実験的に検討したものである.放熱特性としては,温度効率,空気のエンタルピーそして潜熱放熱完了時間を取り上げ,諸因子としては蓄熱槽入口空気温度と湿度,噴射空気流量そして潜熱蓄熱材混合水の充てん高さを採用した.実験結果として,マイクロカプセル化潜熱蓄熱材を水中に混合分散した潜熱蓄熱槽からの採熱を空気泡群で行う場合,空気泡群への水分の蒸発潜熱が,その移動熱量の大部分を占めることが定量的に明らかになった.さらに,空気泡群とマイクロカプセル化潜熱蓄熱材混合水との直接接触熱・物質交換により,高効率な熱・物質交換が可能であることを解明した.最終的に潜熱放出を伴う気-液直接接触熱交換に関する,温度効率,蓄熱槽出入口空気エンタルピーおよび潜熱放熱完了時間に対する無次元整理式の導出を行った.

DOI： 10.18948/shase.24.74_59

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer Verlag  

This paper has concerned the heat and mass transfer of a water film falling down a tilted plate with radiant heating and water evaporation. A cluster of physical models was developed for evaluating the properties of heat and mass transfer. A fully implicit control-volume finite-difference procedure was used to solve the coupling equations. The effects of various parameters on heat and mass transfer were investigated. The results showed that the mass fraction of water vapor in ambient atmosphere and the flow turbulence played key roles in the heat and mass transfer. The ambient atmospheric temperature dramatically affected the sensible heat flux. However its effect on the latent heat flux is negligibly small. The magnitude of solar incident flux had an intense influence on the water film temperature. © Springer-Verlag 1999.

DOI： 10.1007/s002310050274

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記述言語：日本語  

DOI： 10.1299/kikaib.64.1462

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記述言語：日本語  

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記述言語：日本語   出版者・発行元：社団法人日本機械学会  

The present study deals with the heat storage characteristics of the inclined rectangular vessel packed with spape-stabilized paraffin plates as a latent heat storage material by numerical analysis. It was found that the heat storage characteristics were remarkedly affected by the inclination angle of the rectangular vessel and the heat transfer medium flow direction, due to the presence of natural convection in the fluid flow channel between the paraffin plates. Numerical results revealed flow patterns, temperature profiles and heat storage characteristics for various inclination angles, inlet velocities and temperatures of the heat transfer medium fluid, and widths of the fluid flow channel.一般に、潜熱蓄熱槽の蓄熱過程では、熱媒体流速を極力小さくすることにより、圧力損失の軽減や熱媒体の持つ熱エネルギーの有効利用を図る試みがなされており、さらに潜熱の放熱過程では、小さな熱媒体流速により、一定の高温水準での熱抽出が可能となる。例えば、齊藤らの研究においては、球カプセルを充填した円筒形蓄熱槽内熱媒体の流速は10mm/s以下の低流速領域である。また、阿部らの報告した円筒状蓄熱材充填蓄熱槽内の熱媒体流速は約0.5mm/sと極めて小さいものである。このように、熱媒体の強制対流による流速が小さい場合には、状況によって蓄熱槽内の熱媒体流路に発生した自然対流がその熱伝達特性を大きく左右することになり、強制－自然共存対流の検討が必要となる。流路内の強制－自然共存対流に起因する伝熱現象は流路形状、重力方向に対する強制対流の流れ方向、流路の加熱または冷却条件など諸因子によって複雑な様相を呈する。強制－自然共存対流伝熱現象は、電子機器の除熱や大洋州熱器などにおいて数多く見られる。この場合の伝熱現象の解析的扱いは矩形流路壁の熱境界条件として等温そして等熱流束の固定条件の場合が大半で、その壁面温度がその内部に有る相変化物質の潜熱吸収や放出により変化するような場合はほとんど取り上げられていない現状にある。著者らは垂直配置した矩形潜熱蓄熱槽内の蓄熱及び放熱特性に大きく影響を及ぼすことを明らかにしている。例えば、熱媒体入口流速がV=0.2mm/sの放熱過程においては、下向き流れ（強制対流方向は重力方向と同じ場合）においては、上向き流れ（強制対流方向は重力方向と逆の場合）に比較して、流路内に発生した自然対流が熱伝達を阻害し、その放熱完了時間を大幅に増大する結果となる。本研究は、平板状形状安定化処理パラフィン潜熱蓄熱材が充填された矩形蓄熱槽を研究対象とし、二次元非定常数値解析により、矩形蓄熱槽を傾斜することにより自然対流を抑制した場合における強制－自然共存対流熱伝達の蓄熱特性に及ぼす効果を検討するものである。さらに、熱媒体蓄熱槽入口流速、入口温度及び熱媒体流路幅の蓄熱特性に及ぼす影響も併せて検討を行ってある。

DOI： 10.1299/kikaib.64.526

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その他リンク： http://ousar.lib.okayama-u.ac.jp/11193

記述言語：英語  

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記述言語：日本語   出版者・発行元：社団法人日本機械学会  

This paper deals with the heat transfer characteristics of a liquid-liquid direct contact operation in which a Perfluorocarbon (PFC) liquid is released in a hot water stream, a low-grade heat source such as urban sewage, for the purpose of heat recovery from it. The paper reports on a set of experiments in which a PFC liquid (1800 kg/m^3 at 20℃) was continuously injected from a single, downward-facing nozzle into a slow, upward flow of hot water to be disintegrated into droplets descending in, and thereby heated from the water flow. The results of the experiments show how the size distribution and the translational motions of the droplets affect the overall coefficient for the water-flow-to-droplets heat transfer and also the temperature effectiveness for the droplets.近年、未利用エネルギー活用の観点から、工場や家庭温排水などを熱源として利用する廃熱回収用熱交換器の開発が急務となっている。従来のシェルアンドチューブなどの隔壁型交換器では、伝熱面に排水中のごみやスケールが堆積し、その伝熱効率が著しく低下する等の問題点があった。この問題解決として、このような汚濁排水中に、非水溶性熱媒体を噴射・注入し、直接接触熱交換により、熱抽出が可能となる。このような直接接触熱交換法は、個体壁伝熱面の汚れによる伝熱効率低下の問題がなくなり、廃熱回収用熱交換方式として極めて有効である。さらに、この熱交換法は、個体壁を介さないために高い熱通過率が得られ、小温度差での熱交換に有効である。また、液－液の直接接触する界面が、そのまま伝熱面に相当するため、単位体積当たりの伝熱面積が増加する利点を有する。本研究は、下水等の汚れた熱水源より効率的な熱回収をする手段として液液直接熱交換法に注目したものであり、熱回収媒体としてフッ素系不活性液体を熱源水へ噴射し、形成したフッ素系不活性液滴群と熱源水の直接接触による、流動及び熱伝達特性を検討するものである。すなわち、円形単孔ノズルから高密度のフッ素系不活性液体を熱源である温水槽へ上部より噴射し、その液滴群形成過程の観察及び液滴群の流れの特性の解明を通じて、熱水源からの直接熱交換法による熱抽出に関する基礎特性を明らかにすることを目的とする。最終的に、この種の熱源水よりの熱回収媒体としてフッ素系不活性液体を用いた場合における実用に寄与する無次元熱伝達率等に関する実験整理式の検討をも行うものである。

DOI： 10.1299/kikaib.64.3838

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その他リンク： http://ousar.lib.okayama-u.ac.jp/11190

記述言語：日本語   出版者・発行元：公益社団法人 空気調和・衛生工学会  

本報告は,ペレット状の形状安定化処理パラフィン潜熱蓄熱材粒子を充てんした流動層型潜熱蓄熱槽の放熱特性についての実験結果を述べたものである.潜熱蓄熱材として蓄熱状態にあるペレット状の形状安定化処理パラフィン潜熱蓄熱材粒子を充てんした円筒状潜熱蓄熱槽に,熱媒体としての低温空気を吹き込み,その蓄熱材粒子群を流動層化して,直接接触熱交換により温空気を得る放熱特性を検討したものである.その放熱特性である潜熱蓄熱槽出口空気温度,および放熱完了時間に及ぼす空気速度や温度など各因子の影響について,本流動層型の潜熱蓄熱層と固定充てん層型潜熱蓄熱槽の場合との比較検討を行った.その結果,本流動層型潜熱蓄熱槽では,固定層型の場合に比較し同一送風動力下での潜熱放熱完了時間が大きく短縮されることが明らかとなり,さらに蓄熱槽出口空気温度および放熱完了時間に関する無次元整理式の導出に成功した.

DOI： 10.18948/shase.23.69_29

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PLENUM PUBL CORP  

Measurements of surface tension have been performed to determine the effects of both temperature and concentration on the surface tension of aqueous solutions of D-Sorbitol, potassium chloride, and ammonium chloride. A differential capillary-rise method was employed for the measurements. The results showed that the surface tension of rest solutions increased as the temperature decreased and that the surface tension of chloride solutions increased with an increase in its concentration. while for D-Sorbitol solution the surface tension decreased with increasing concentration. Correlation equations for the surface tension of three aqueous binary solutions as a function of temperature and concentration were determined.

DOI： 10.1007/BF02575346

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PLENUM PUBL CORP  

The paper is concerned with measurements of the surface tension of aqueous binary solutions at low temperatures. The effects of both temperature and concentration on the surface tension of CaCl2, NaCiO(3), and propylene glycol have been investigated. A differential capillary-rise method was employed for the measurements. The results showed that the surface tension of CaCl2 and NaClO3 increases monotonically as the concentration of the solution increases, while for the propylene glycol solution the surface tension decreases with increasing concentration. The surface tension of the testing liquids was found to be an almost-linear function of temperature from 20 degrees C to just above the freezing temperature. Equations for the surface tension of the three aqueous binary solutions as a Function of temperature and concentration are presented.

DOI： 10.1007/BF02575169

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

This paper deals with the transient heat storage characteristics of high-density polyethylene pellets used as a latent heat storage material by the condensed heat from the ethylene glycol vapor. The polyethylene pellets are fabricated by the shape-stabilization treatment in which the molten pellets maintain the same shape as the solidified ones. The polyethylene pellets packed in the cylindrical heat storage vessel are melted by the condensed heat from the flowing vapor. The effects of vapor temperature, flow rate and the amount of the pellets on the latent heat storage characteristics are investigated experimentally. Moreover, the vapor movement among the packed pellets is enhanced by using the partition plate in the pellets layer. The nondimensional correlation equations of the completion time of heat storage are defined in terms of various nondimensional parameters.

DOI： 10.1299/kikaib.63.605_282

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記述言語：日本語  

DOI： 10.1299/kikaib.63.4021

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記述言語：日本語   出版者・発行元：公益社団法人 日本冷凍空調学会  

This paper has dealt with melting heat transfer characteristics of ice water slurry in an inside tube of horizontal double tube heat exchanger in which a hot water circulated in an annular gap between the inside and outside tubes. Two kinds of heat exchangers were used; one is made of acrylic resin tube for flow visualization and the other is made of stainless steel tube for melting heat transfer measurement. The result of flow visualization revealed that ice particles flowed along the top of inside tube in the ranges of small ice packing factor and low ice water slurry velocity, while ice particles diffused into the whole of tube and flowed like a plug built up by ice particles for large ice packing factor and high velocity. Moreover, it was found that the flowing ice plug was separated into numbers of small ice clusters by melting phenomenon. Experiments of melting heat transfer were carried out under some parameters of ice packing factor, ice water slurry flow rate and hot water temperature. Consequently, the correlation equation of melting heat transfer was derived as a function of those experimental parameters.

DOI： 10.11322/tjsrae.14.265

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記述言語：日本語   出版者・発行元：社団法人日本機械学会  

This paper deals with fluidization and heat storage characteristics of shape-stabilized latent heat storage particles packed into a fluidized bed-type heat storage vessel. The shape-stabilized latent heat storage material consists of normal paraffin (pentacosane C_<25>H_<52>, latent heat 164 kJ/kg, melting point of 327.2 K) as a latent heat material, and polyethylene as a shape-stabilizing material. The pressure losses both on fluidized and on fixed particle layers were measured in order to investigate flow behavior in the heat storage vessel. It was found that the pressure loss of the fluidized particle layer was lower than that of the fixed particle layer. Furthermore, the effects of hot air flow rate, inlet air temperature and the amount of heat storage particles packed into the heat storage vessel on the completion time of the heat storage process were investigated. As a result, the nondimensional correlations for the completion time of the heat storage process were expressed in terms of nondimensional pumping power, the Stefan number and the ratio of the packed particle layer height to the diameter of the cylindrical heat storage vessel.一般に固－液相変化潜熱蓄熱材（PCM）は、カプセル内に充填して使用される例が多い。このカプセル型潜熱蓄熱システムは、カプセル化に要する費用が多くかかり、そして、熱伝導率の小さなプラスチック材をカプセルとするため、その熱抵抗により潜熱蓄熱材の相変化温度付近での効率的熱抽出が出来なくなるなどの問題がある。例えば平板状の形状安定化潜熱蓄体に厚さ0.5mm～2.0mmのポリプロピレン製被覆（熱伝導率 0.195W/(m・K)）を施した場合、放熱完了時間は被覆のない場合に比較して7～15％増大することが確認されている。これらの問題点の解決策として、形状安定化潜熱蓄熱体を用いた脱カプセル化技術がある。形状安定化潜熱蓄熱体は担持材により潜熱物質の流出がなく、固体状粒子と同じ形状を保つものである。従って融解潜熱物質の流出防止用としてのカプセルに封入する必要なく、上述のカプセル型潜熱蓄熱の問題点を解決できるものである。さらに潜熱物質であるパラフィンは熱伝導率が0.194(60℃)～0.294(20℃)W/(m・K)と小さいため、これに熱伝導率が0.291(60℃)～0.333(20℃)W/(m・K)と大きなポリエチレンを混合して得られる形状安定化潜熱蓄熱体は、潜熱物質のみに比較して熱伝導率増大することも特徴である。また、カプセル型潜熱蓄熱システムにおいては、一般にカプセル蓄熱体を蓄熱槽に固定して使用する、いわゆる固定充填層を用い熱媒体を流動させて熱交換を行う方法が主になされてきた。固定充填層の場合には、固定された蓄熱体と熱媒体の熱交換により、熱媒体の流れ方向への温度差（温度勾配）が大きくなり、均一な熱交換が不可能となる。このため、蓄熱材と熱媒体が小温度差の蓄熱システムには向いておらず、下流域での蓄熱完了に時間がかかるなどの問題点がある。この問題点の解決方法としては、粒子状蓄熱材を流動化させ、蓄熱槽を流動層とし、その蓄熱粒子の混合作用により層内において均一な熱交換を行うことにより、熱媒体と蓄熱材粒子を小温度差にても熱交換させることが考えられる。さらに流動層型潜熱蓄熱槽にて蓄熱された球状潜熱蓄熱体を、空気流により管内高速搬送し、最終的に利用側での空気暖房や温水製造媒体として利用する、新たな潜熱蓄熱体システムが構築されれば、熱輸送時のポンプ動力も大きく削減されることにより、省エネルギーに大きく貢献すると考えられる。本研究では、上述の新たな潜熱蓄熱システムの蓄熱槽として、球状に成形した形状安定化潜熱蓄熱体を流動蓄熱体とし、熱媒体に空気を用いた、流動層型の潜熱蓄熱槽の可能性を検討するものである。本報告では、蓄熱槽内の流動化状態を知る上で重要となる可視化用試験部を用いた球状潜熱蓄熱体の流動状態の観察結果を示すとともに、蓄熱槽内の圧力損失と空塔流速の関係を定量的に明らかにし、蓄熱槽を固定充填層とした場合との比較・検討を行う、さらに、潜熱蓄熱の際に重要な要素となる潜熱蓄熱完了時間について送風動力、入口温度および蓄熱材粒子の静止層高さとの関係を流動層および固定充填層の場合について実験的に明らかにする。最終的に、潜熱蓄熱完了時間を予測する無次元整理式の提案を行うものである。

DOI： 10.1299/kikaib.63.2175

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その他リンク： http://ousar.lib.okayama-u.ac.jp/11196

記述言語：日本語   出版者・発行元：JAPAN SOCIETY OF THERMOPHYSICAL PROPERTIES  

本論文は，温排水や下水等の汚濁熱源からの熱抽出を液液直接接触熱交換法にて行う際の熱媒体として有望なフッ素系不活性液体混合物に関する諸物性の測定法とその測定結果について報告するものである．フッ素系不活性液体混合物の物性である密度，動粘度，水との界面張力，比熱，熱伝導率のそれぞれについて，温度T＝273.15～323.15Kの広範な温度領域においての測定を行った．また，各物性の温度依存性に関する関係式の誘導を行った．

DOI： 10.2963/jjtp.11.123

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その他リンク： https://jlc.jst.go.jp/DN/JALC/00050220021?from=CiNii

記述言語：日本語   出版者・発行元：公益社団法人 空気調和・衛生工学会  

新たな潜熱蓄熱システムの構築を目的として,ペレット状の形状安定化処理パラフィン潜熱蓄熱材を充てんした流動層型潜熱蓄熱槽内の蓄熱材粒子の流動,および蓄熱特性についての実験的研究を行った.ペレット状の形状安定化潜熱蓄熱材は,固-液相変化潜熱蓄熱材(パラフィン)と,結晶性樹脂であるポリエチレンの混合物で,潜熱蓄熱材が融解してもその形状は固相の状態を保つものである.本研究では,熱媒体として空気,そして潜熱蓄熱材としてペレット状形状安定化処理パラフィン潜熱蓄熱材を用いた流動層型の潜熱蓄熱法を提案し,その流動および蓄熱挙動に及ぼす空気速度や温度など各因子の影響について固定充てん層型の潜熱蓄熱槽の場合と比較検討した.その結果,本流動層型潜熱蓄熱槽では,固定層型の場合に比較し同一送風動力下での潜熱蓄熱完了時間が大きく短縮されることが明らかとなり,さらに蓄熱完了時間に関する無次元整理式を導出した.

DOI： 10.18948/shase.22.66_77

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：PLENUM PUBL CORP  

Measurements of the surface tension have been carried out to determine the effects of both temperature and concentration on the surface tension of aqueous solutions of sodium chloride, propylene glycol, and ethylene glycol. A differential capillary-rise method was employed for the measurements. The results show that the surface tension of the ethylene glycol solution and the propylene glycol solution increases as the concentration of the solution decreases, while for the sodium chloride solution the surface tension increases monotonically as the concentration increases. The surface tension of the liquids was found to be an almost-linear function of temperature from 20 degrees C to just above the Freezing temperature. Equations for the surface tension of the three binary aqueous solutions as a function of temperature and concentration are presented.

DOI： 10.1007/BF01443405

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記述言語：日本語  

DOI： 10.11322/tjsrae.13.293

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

An experimental study was made of the forced convection freezing characteristics on the convex wall of a return bend with a rectangular cross section. Observations were carried out for duct heights of 17 and 30 mm, a duct width of 300 mm, and a radius of curvature of 159 mm. The convex wall temperature was uniformly maintained below the freezing temperature of water, and the concave wall was insulated. It was found that a stepwise ice layer forms on the convex wall of a return bend and that the step position at the steady-state condition is closely dependent on both the water flow velocity and the cooling temperature ratio.

DOI： 10.1016/0894-1777(95)00015-1

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER VERLAG  

Experiments have been performed to investigate the freezing heat transfer characteristics in a return bend with a rectangular cross section. The experiments were carried out for two kinds of duct heights of 30 and 50 mm under the fixed size of 300 mm in duct width and 159 mm in curvature radius of convex wall. Both the convex and concave walls of a return bend were kept less than the freezing temperature of water. It was found that the freezing characteristics on the convex wall are markedly different from those on the concave wall of a return bend, and that the cooling temperature ratio is one of the most important parameters on the forced-convection freezing heat transfer in a return bend.

DOI： 10.1007/BF01602764

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer-Verlag  

Experiments have been performed to investigate the freezing heat transfer characteristics in a return bend with a rectangular cross section. The experiments were carried out for two kinds of duct heights of 30 and 50 mm under the fixed size of 300 mm in duct width and 159 mm in curvature radius of convex wall. Both the convex and concave walls of a return bend were kept less than the freezing temperature of water. It was found that the freezing characteristics on the convex wall are markedly different from those on the concave wall of a return bend, and that the cooling temperature ratio is one of the most important parameters on the forced-convection freezing heat transfer in a return bend. © 1995 Springer-Verlag.

DOI： 10.1007/BF01602764

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER VERLAG  

An experimental study of the transient solidification of an aqueous binary solution from a vertical cooled plate is reported in this paper. A copper plate of the flow duct, which has 50 mm x 70 mm in cross-sectional dimension and 500 mm in length, was cooled uniformly. Ethylene-glycol solution was adopted as a testing liquid. The dependence of the plate wall temperature, the flow rate, the entry-liquid concentration, and the entry-liquid temperature on the solidification characteristics were extensively determined. The data reveal that the characteristics of the frozen layer at both the onset and the steady state could be favorably classified as a function of Reynolds number and the cooling temperature ratio. The correlation of the averaged frozen-layer thickness at the steady state was determined.

DOI： 10.1007/BF01476520

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Springer-Verlag  

An experimental study of the transient solidification of an aqueous binary solution from a vertical cooled plate is reported in this paper. A copper plate of the flow duct, which has 50 mm×70 mm in cross-sectional dimension and 500 mm in length, was cooled uniformly. Ethylene-glycol solution was adopted as a testing liquid. The dependence of the plate wall temperature, the flow rate, the entry-liquid concentration, and the entry-liquid temperature on the solidification characteristics were extensively determined. The data reveal that the characteristics of the frozen layer at both the onset and the steady state could be favorably classified as a function of Reynolds number and the cooling temperature ratio. The correlation of the averaged frozen-layer thickness at the steady state was determined. © 1995 Springer-Verlag.

DOI： 10.1007/BF01476520

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記述言語：日本語   出版者・発行元：公益社団法人 日本冷凍空調学会  

An experimental study has been performed to investigate the freezing characteristics of an aqueous binary solution droplet on a cooled wall. Pure water, ethylene-glycol aqueous solutions of 1to 10 mass%, and NaCl aqueous solutions of 1 to 15 mass% in concentration were adopted as the testing solutions. The droplet was frozen under a variety of cooling conditions such as wall temperature, air temperature, air velocity, and solute concentration in both the static atmosphere and the cold air flow. The observations on both the freezing characteristics and the morphologies of the droplet were extensively carried out. In addition, the inside flow of the droplets were observed. It was found that the morphology of the droplet on the cooled wall varied markedly depending on the solution, which appears to be mainly caused by the difference in the surface tension of the solution. On the other hand, under the conditions with a cold air flow, initial freezing point of the droplet was found to be mainly owing to the cooling rate between the cooled wall and the cold air.

DOI： 10.11322/tjsrae.12.63

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DOI： 10.11322/tjsrae.11.79

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE BV  

Melting points of some kinds of molten salts have been determined, and also supercooling characteristics of potassium thiocyanate KSCN and calcium chloride CaCl2 have been investigated. Molten salt has been utilized as a thermal storage material, cooling material for the nuclear reactor, refinement of the petroleum, fuel battery, molten-salt reactor because of its excellent thermal characteristics and chemical stability. Therefore, it is important for its utilization to store the data of thermophysical properties to control both the melting and solidification processes. The sample of molten salt is both heated and cooled depending on the prescribed heating-cooling temperature curves in the electric furnace with a controller. The melting points were determined as the constant temperatures which can be observed for some period in the cooling process. Furthermore, the supercooling characteristics were investigated under various sample masses and cooling rates as parameters. It was found that the degree of supercooling depended closely on both the cooling rate and the sample mass.

DOI： 10.1016/0040-6031(93)80439-H

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASME-AMER SOC MECHANICAL ENG  

An experimental study has been performed to investigate the freezing characteristics of an aqueous binary solution along a horizontal cooled tube. A copper coaxial cooling tube was set horizontally in a flow duct which has cross-sectional dimensions of 120 mm x 200 mm. Ethylene-glycol solution was utilized as a test solution. Observation of frozen layer, measurement of heat-transfer coefficient, and visualization of flow pattern were extensively carried out under a variety of concentration of the solution, initial temperature, cooling temperature, and flow velocity as parameters. It was found that the characteristics of the frozen layer could be well grouped using both the Reynolds number and the cooling temperature ratio, and that the flow field had a considerable effect on the characteristics of the frozen layer. The correlations of the averaged frozen-layer thickness at the steady state were determined.

DOI： 10.1115/1.2902157

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：BEGELL HOUSE, INC  

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SPRINGER  

Measurements of both the velocity and turbulence-intensity distributions above an ice-layer surface along flow direction have been performed to clarify the ice-layer transition phenomena observed in a rectangular duct. The test duct which has a lower cooled wall kept less than the freezing temperature of water with cross-sectional dimension of 50 mm by 19 mm was used in the present measurements. The velocity and turbulence-intensity distributions in the test duct were measured using Laser Doppler Velocimeter set up on the two-dimensional traversing table. The freezing experiments were carried out under the condition of uniform water-flow rate even after the ice layer has developed in the test duct. It was found that inlet water flow tended to be laminarized under an influence of developing ice layer, and that onset of the ice-layer transition phenomena might be closely related to an increase in turbulence intensity in the water flow above the developing ice-layer surface.

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記述言語：日本語  

DOI： 10.11322/tjsrae.10.37

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記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELSEVIER SCIENCE PUBL B V  

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記述言語：日本語   出版者・発行元：The Japan Society of Mechanical Engineers  

An experimental study has been performed to investigate the freezing behavior on the convex wall of a return bend with a rectangular cross section. The experiments were carried out for the duct heights of 17mm and 30mm with a duct width of 300mm and a radius of curvature of 159mm. The convex wall temperature was uniformly maintained below the freezing temperature of water, while the concave wall was insulated. It was found that step wise ice formation was observed on the convex wall of the return bend and that the step position at the steady-state condition was closely dependent on both the water-flow velocity and the cooling-temperature ratio.

DOI： 10.1299/kikaib.58.2863

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記述言語：日本語   出版者・発行元：JAPAN SOCIETY OF THERMOPHYSICAL PROPERTIES  

溶融塩は、 熱媒体、 化学反応媒体として優れているため、 この特性を応用した溶融塩関連技術の研究開発が進められている。 これらの応用技術を確立する上で、 溶融塩に関する熱物性値を把握することが必要不可欠であり、 信頼できるデータの蓄積が期待されている。<br>本研究は、 溶融塩の基本的な物性値の一つである融点の測定を行い、 合わせて過冷却および凝固挙動について検討したものである。

DOI： 10.2963/jjtp.6.154

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記述言語：日本語  

DOI： 10.11322/tjsrae.9.43

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

An experimental study has been performed to investigate the de-icing heat transfer characteristics along a horizontal cylinder immersed within a cold forced air flow with spraying seawater. Experiments were carried out under a variety of experimental parameters such as air velocity, air temperature, droplet diameter, and spraying liquid content. The location of onset of the ice pieces was observed to change markedly according to the condition of droplet size and air stream. It was also found that the heat-transfer characteristics along the cylinder under de-icing conditions were mainly affected by sensible heat values of the impinging droplets.

DOI： 10.1299/kikaib.57.4209

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE INC  

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記述言語：英語   掲載種別：記事・総説・解説・論説等（国際会議プロシーディングズ）  

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記述言語：日本語   出版者・発行元：日本熱物性学会  

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担当区分：筆頭著者   記述言語：英語  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

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担当区分：筆頭著者   記述言語：英語  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Electrodialysis using ion-exchange membranes is a means of producing dilute and condensate under the influence of an applied electric potential difference of saltwater. In this study, we have investigated the transport process of ions in the electrodialysis stack under the influence of an applied electric field. Under a limiting current density, the ion concentration totally vanishes at the exit of the diluate channel so that the electric resistance goes infinity toward the diluate side of the cation exchange membrane, which is referred to as concentration polarization. The effect of the flow field on this limiting current density, which is one of the most important design parameters in the electrodialysis stacks, have been investigated by measurement of the electric resistance and concentration.

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

The heat transfer of natural convection from upward facing-horizontal heated surface which a heated annular duct was placed above was investigated experimentally. The relationship of the heat transfer to the distance of between the horizontal heated surface and the heated ducts was examined. The flow fields around the heated surface and heated ducts were visualized. With decreasing the distance, the ascending flow velocity in the heated ducts becomes low and the reverse flow occurs. The heat transfer increases with decreasing the distance. Inserting a heated inner duct enhances the heat transfer.

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

The purpose of this research is phase change characteristic evaluation of the nanosuspension type heat storage as latent heat material. The target heat storage zone of this study is 50-100℃ as for using of hot spring heat or factory exhaust heat. Tetracosane (50.6℃ of melting point) is used for dispersion material as a latent heat storage material of a nanosuspension. Tetracosane in the nanosuspension is dispersed by about 200 nanometers of average particle diameter in continuous water phase. A latent heat storage material is dispersed by using an ultrasonic homogenizer. This paper deals with the phase change characteristics that estimated by using differential scanning calorimeter. The heating rate and the composition of tetracosane are chosen as experimental parameter.

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

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記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

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記述言語：日本語   出版者・発行元：公益社団法人 日本冷凍空調学会  

機能性流体に使用する蓄熱粒子のナノサイズ化は，凝集や合一化による分離等の欠点を生じる．このため，ナノ粒子懸濁液を凝集が生じない低濃度で保存し，使用の際に任意の濃度まで濃縮する凍結濃縮法に着目した．本研究では，ナノシリカ粒子懸濁液の粒子径および初期粒子濃度が凍結・凍結濃縮現象におよぼす影響について実験的に検討し，シリカ粒子径の減少によって過冷却度の増大と低凝固速度での氷結晶構造の拡大を測定し，さらにシリカ粒子の結晶粒界付近の偏在を確認した．一方，界面前進凍結法によるシリカ粒子懸濁液の凍結濃縮実験より，シリカ粒子のナノサイズ化は撹拌条件では凍結濃縮現象に影響しないが，無撹拌条件では沈殿現象を抑制し，適切な凝固速度下にて凍結濃縮を行えば，マイクロ粒子よりも高い凍結濃縮効果を得られる可能性があることを確認した．

DOI： 10.11322/tjsrae.14-59

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その他リンク： https://jlc.jst.go.jp/DN/JLC/20013102751?from=CiNii

記述言語：英語  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：日本語   出版者・発行元：日本冷凍空調学会  

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記述言語：英語  

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