Transactions of the Japan Society of Mechanical Engineers. B最新文献

SSRT and fatigue crack growth properties of two types of high strength austenitic stainless steels in high pressure hydrogen gas 两种高强奥氏体不锈钢在高压氢气中的SSRT和疲劳裂纹扩展特性

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-12-01 DOI: 10.1299/KIKAIA.79.1726

H. Itoga, T. Matsuo, Akihiro Orita, H. Matsunaga, S. Matsuoka

{"title":"SSRT and fatigue crack growth properties of two types of high strength austenitic stainless steels in high pressure hydrogen gas","authors":"H. Itoga, T. Matsuo, Akihiro Orita, H. Matsunaga, S. Matsuoka","doi":"10.1299/KIKAIA.79.1726","DOIUrl":"https://doi.org/10.1299/KIKAIA.79.1726","url":null,"abstract":"The susceptibility to hydrogen embrittlement of two types of high strength austenitic stainless steels containing a small amount nitrogen and niobium were investigated by conducting a series of slow strain rate tests (SSRT) and fatigue crack growth tests in hydrogen gas with a pressure of around 100 MPa. The JIS-SUS304 and JIS-SUS316L austenitic stainless steels were also tested for a comparative purpose. In JIS-SUS304, the tensile strength and reduction of area in hydrogen gas were much lower than those in air. In contrast, in JIS-SUS316L, the degradation of those tensile properties in hydrogen gas was not so significant. The high strength austenitic stainless steels also exhibited an excellent resistance both in tensile strength and ductility in hydrogen gas. In JIS-SUS304, the fatigue crack growth in hydrogen gas was 10 times as fast as that in air, while the factor of acceleration remained within 1.5 3 in JIS-SUS316L and the high strength austenitic stainless steels. It was presumed that, in those high strength austenitic stainless steels, a small amount of added elements, N and Nb, increased the strength level as well as the stability of austenitic phase, which thereby led to the excellent resistance against hydrogen embrittlement.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114780229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

Influence of Initial Systems on the Renewal Planning of Energy Supply Systems for a Hospital 初始系统对某医院供能系统更新规划的影响

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-11-18 DOI: 10.1299/KIKAIB.79.2312

S. Yoshida, Akira Yoshida, Koichi Ito, Y. Amano

{"title":"Influence of Initial Systems on the Renewal Planning of Energy Supply Systems for a Hospital","authors":"S. Yoshida, Akira Yoshida, Koichi Ito, Y. Amano","doi":"10.1299/KIKAIB.79.2312","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.2312","url":null,"abstract":"In this study, a renewal planning problem of energy supply system is formulated as a large scale mixed-integer linear programming problem, in which the objective function to the minimized is the average value of annual total cost during system’s evaluation period. By adopting the programming language AMPL and CPLEX solver, a numerical study is carried out for a hospital, where electrical(e.g., heat pump) and gas(e.g., gas engine cogeneration) systems are compared together with arbitrary combination one, which is composed of electrical and gas driven pieces of equipment, by focusing particularly on the influence of initial system’s difference. The main results obtained are as follows: (a) If the initial system is gas one, it is better to renew it to the electrical one as soon as possible due to relatively low energy efficiency of gas utilizing pieces of equipment, the high price of gas input energy and so on. (b) If the initial system is electrical one, the optimal renewal year becomes relatively later year, because it is economically better to use the initially installed high efficiency system as long as possible. (c) Theoretically, the arbitrary combination system is of course the best renewal one. However, there is no economic difference between the arbitrary combination system and the electrical one.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131500682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fdtd analysis of nanoscale temperature distribution induced by near-Field photothermal effect 近场光热效应诱导纳米尺度温度分布的Fdtd分析

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-11-18 DOI: 10.1299/KIKAIB.79.2254

Shouhei Fukuyama, Y. Taguchi

{"title":"Fdtd analysis of nanoscale temperature distribution induced by near-Field photothermal effect","authors":"Shouhei Fukuyama, Y. Taguchi","doi":"10.1299/KIKAIB.79.2254","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.2254","url":null,"abstract":"We have developed a novel nanoscale patterning method of self-assembled monolayer (SAM) using near-field light. This method utilizes the thermal desorption of constituent molecules of a SAM (e.g. the desorption temperature of Octadecanethiol on Au is 130~230 o C) through the irradiation with near-field light, which can make noncontact and noncontaminating patterning of the SAM at nanoscale. In this paper, the near-field photothermal effect is numerically analyzed by the finite difference time domain (FDTD) method, and the electromagnetic field intensity and temperature distributions are estimated. The sample consists of Au thin film as a bonding layer with thiolated molecules of SAM, Ti thin film as an adhesion layer for Au, and SiO 2 substrate. In the analysis, the shape of the near-field optical fiber probe and the thickness of the thin film layer are considered. In the case of the thick Au layer with a double-tapered near-field optical fiber probe, the temperature of the fiber-tip becomes higher than that of Au surface. The strong heating of the probe tip causes a fatal damage of the coating metal of the fiber, therefore it is difficult to couple the high intensity laser into the near-field optical fiber probe in order to reach the desorption temperature. On the other hand, the desorption temperature can be achieved with the 10 nm-thick Au thin film. Moreover, in order to gain high optical intensity enhancements, the triple-tapered near-field optical fiber probe is utilized. Our simulations confirm extremely high temperature distribution on the sample surface by using the triple-tapered near-field optical fiber probe with 10 nm-thick Au thin film layer on 50 nm-thick","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132347467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Improvement of water discharge from gas diffusion layer to gas channel with obliquely-directed micro-grooves arranged inside channel walls 通道壁上斜向微槽改善气体扩散层向气体通道的排水量

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-10-14 DOI: 10.1299/KIKAIB.79.1866

A. Okabe, Y. Utaka

{"title":"Improvement of water discharge from gas diffusion layer to gas channel with obliquely-directed micro-grooves arranged inside channel walls","authors":"A. Okabe, Y. Utaka","doi":"10.1299/KIKAIB.79.1866","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.1866","url":null,"abstract":"Polymer electrolyte fuel cell (PEFC) is expected to be used with the power sources for the automobile and the cogeneration power source for home and so forth. At the cathode-side of a PEFC, oxygen is transported as the reactant gas from gas channel through gas diffusion layer (GDL) to the catalyst layer. However, the large quantity of moisture is generated under the situation of the high power generation. Since, as a result, the moisture blocks transporting oxygen, the cell voltage falls off drastically. The objective of this study is to improve the management of moisture from GDL in gas channels of separator for PEFC. The oblique micro-grooves are manufactured inside gas channel walls. Water from GDL is discharged through the micro-grooves to upper-side of gas channel by surface tension and shearing force generated by air flow. Velocity of water flowing in the micro-grooves was measured by using the laser induced fluorescence method. It was confirmed experimentally that micro-grooves manufactured inside gas channel worked properly, that is, water discharge from GDL to upper-side of channel was succeeded. The water velocity and effective length of micro-grooves to remove water from GDL surface increased with the decrease in inclination angle θ of micro-grooves in this experimental range of θ =20~40 ° . It was shown that the effective length of approximately 200mm, which was overall length of experimental apparatus, was attained.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128870817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

An analysis of quantum effect on the p-V-T relation of cryogenic hydrogen using centroid molecular dynamics method 用质心分子动力学方法分析低温氢的p-V-T关系的量子效应

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-10-14 DOI: 10.1299/KIKAIB.79.1848

H. Nagashima, S. Tsuda, N. Tsuboi, M. Koshi, A. Hayashi, T. Tokumasu

引用次数: 0

A study on equivalence-ratio dependence of minimum ignition energy based on initial burning velocity 基于初始燃烧速度的最小点火能量当量比依赖性研究

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-10-14 DOI: 10.1299/KIKAIB.79.1839

E. Murase, O. Moriue, H. Hashimoto, Isei Matsuzaki

{"title":"A study on equivalence-ratio dependence of minimum ignition energy based on initial burning velocity","authors":"E. Murase, O. Moriue, H. Hashimoto, Isei Matsuzaki","doi":"10.1299/KIKAIB.79.1839","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.1839","url":null,"abstract":"©2013 The Japan Society of Mechanical Engineers Spark ignition of premixed gases was experimentally studied. Minimum ignition energy and initial burning velocity, which is a burning velocity at an initial stage of flame propagation, were measured and their dependences on equivalence ratio were discussed. Minimum ignition energy takes a minimum value when equivalence ratio is around 0.9 for methane/air mixtures, and around 1.5 for n-butane/air mixtures, which corresponds with the study of Lewis and von Elbe. A shadowgraph technique was used to observe the growth of the flame kernels. A burning velocity was measured from the images of the flame kernel, and initial burning velocity was defined as a burning velocity at the moment when the equivalent radius of the flame kernel is approximately 3.0mm. Initial burning velocity takes a maximum value when equivalence ratio is around 0.9 for methane/air mixtures, and around 1.5 for n-butane/air mixtures, while laminar burning velocity of well-grown flame takes a maximum value when equivalence ratio is around 1.1 for both mixtures as known well. This is caused by the curvature of flame surface at the initial stage. It is suggested that the equivalence-ratio dependence of minimum ignition energy is derived from that of initial burning velocity.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121622721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Performance evaluation of solid oxide fuel cell for exergy recuperation of exhaust heat by electrochemical partial oxidation 电化学部分氧化法废热火用回收固体氧化物燃料电池性能评价

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-10-14 DOI: 10.1299/KIKAIB.79.1583

Takayuki Ozeki, T. Nakagaki

{"title":"Performance evaluation of solid oxide fuel cell for exergy recuperation of exhaust heat by electrochemical partial oxidation","authors":"Takayuki Ozeki, T. Nakagaki","doi":"10.1299/KIKAIB.79.1583","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.1583","url":null,"abstract":"©2013 The Japan Society of Mechanical Engineers Electrochemical partial oxidation (EPOx) of methane can convert exhaust heat into electricity as much as difference between change of Gibbs free energy and change of enthalpy. To quantify recuperated heat and converted electric power of EPOx, we simulated the performance of EPOx in the microtubular Solid Oxide Fuel Cell (SOFC) using Gadolinium Doped Ceria as electrolyte. The quasi-two dimensional and non-isothermal model applied to this SOFC simulation, which consisted of three solid layers and two gas layers, considering with mass, energy and chemical species conservation equations as well as detailed electrochemical reaction. The simulation computed temperature and current density distributions, and evaluated energy flow in SOFC. The simulation code was validated by consistency between the simulation result of power generation using H2 as fuel and the result of previous experimental report. The results showed that EPOx could convert 40% of theoretically recuperated heat into the electric power at the operation condition maximizing total regenerated heat.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130653810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

圧縮機の吐出用リード弁における開き遅れ挙動の計算（弁変形-ガス流れ-油膜流れ連成計算のためのモデル化）计算压缩机的喷射引导阀中的打开延迟行为(用于阀变形-气体流-油膜流的连成计算的建模)

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-10-01 DOI: 10.1299/KIKAIB.79.1985

文太吉住, 靖裕近藤, 隆宏諸井, 真司玉野, 洋平森西

引用次数: 3

Thermal conductivity measurement of TBAB hydrate by the transient hot-wire using parylene-coated probe 瞬态热线法测量TBAB水合物的热导率

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-07-17 DOI: 10.1299/KIKAIB.79.1155

T. Nagatomi, Y. Taguchi, R. Ohmura, Y. Nagasaka

{"title":"Thermal conductivity measurement of TBAB hydrate by the transient hot-wire using parylene-coated probe","authors":"T. Nagatomi, Y. Taguchi, R. Ohmura, Y. Nagasaka","doi":"10.1299/KIKAIB.79.1155","DOIUrl":"https://doi.org/10.1299/KIKAIB.79.1155","url":null,"abstract":"©2013 The Japan Society of Mechanical Engineers Semiclathrate hydrate consists of cage structures composed of water molecules and ionic large guest molecules, which distinguish semiclathrate hydrate from normal clathrate hydrate. Semiclathrate hydrate is stable under atmospheric pressure condition and at near room temperature. This is the reason semiclathrate hydrate is expected to be used in various novel technologies, for example use as a cool-energy storage agent and gas separator. However, there is little knowledge about thermophysical properties of semiclathrate hydrate. Up to the present, few experimental data on its thermal conductivity have been reported. Thermal conductivity is necessary for the evaluation of industrial formation process of semiclathrate hydrate and heat transfer performance of semiclathrate hydrate used as cool-energy storage agent. The present paper reports measurements of the thermal conductivity of Tetra Butyl Ammonium Bromide (TBAB) hydrate by the transient hot-wire technique using a newly developed Parylene-coated probe, in which a metallic wire is coated with a thin electrical insulation layer formed by a chemical vapor deposition of poly-para-xylyene polymer. In order to confirm the reliability of the probe, we have performed check measurements on the thermal conductivity of toluene and water. We have measured the thermal conductivity of TBAB hydrate in the temperature range from 193 to 282 K with the uncertainty of ±2 %. It is found that the thermal conductivity of TBAB hydrate is less than 17 % of that of ice with almost no temperature dependence and its absolute value is lower than that of normal clathrate hydrate such as methane hydrate.","PeriodicalId":331123,"journal":{"name":"Transactions of the Japan Society of Mechanical Engineers. B","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114113633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Active noise cancellation of ducted fan using real-time acoustic modal analysis 基于实时声模态分析的管道风机主动降噪

Transactions of the Japan Society of Mechanical Engineers. B Pub Date : 2013-07-15 DOI: 10.1299/KIKAIB.79.739

Kenichiro Nagat, Yutaro Suzuki, Ytizo Inokuchi, H. Oinuma, Tatsuya Ishll, N. Yamasaki

引用次数: 2