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 {BV}  

DOI： 10.1016/j.ijimpeng.2023.104514

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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：The American Society of Mechanical Engineers  

DOI： 10.1115/1.4056438

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掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/acs.langmuir.1c01381

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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 Society of Mechanical Engineers  

DOI： 10.1299/jamdsm.2021jamdsm0054

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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 Science and Business Media LLC  

DOI： 10.1007/s40964-021-00185-3

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その他リンク： https://link.springer.com/article/10.1007/s40964-021-00185-3/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

This paper presents an easy-to-use theoretical method and an efficient numerical method for solving free vibrations and transient responses of a circular plate coupled with fluid subjected to impact loadings and provides insights into various coupling cases with these developed methods. The Kirchhoff plate theory, Mindlin-Reissner plate theory, and the linear velocity potential function are used. The wet mode of the coupled system is described as the superposition of dry modes of the plate, which has been considered in few studies. The natural frequencies and corresponding mode shapes are solved using the orthogonality of dry modes. The transient responses of the plate are then solved using the superposition of the wet modes and the orthogonality of dry modes. To validate the theoretical results, an efficient and flexible finite element method is proposed and verified by comparing with commercial software. The four-node mixed interpolation of the tensorial component quadrilateral plate finite element (MITC4) and the eight-node acoustic pressure element are used to model the plate and the fluid, respectively. The theoretical and numerical methods provide reliable and accurate results. Parametric studies are performed to investigate the influence of geometric sizes, plate material properties, and fluid properties on the natural frequencies of the coupled system. A coupling parameter of fluid-structure interaction is proposed. The non-dimensional added virtual mass incremental (NAVMI) factor decreases as the coupling parameter increases. Besides, the influence of fluid on wet modes of the plate decreases with order.

DOI： 10.1115/1.4050319

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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 Science and Business Media B.V.  

DOI： 10.1007/s10999-021-09573-7

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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）   出版者・発行元：American Society of Mechanical Engineers  

<title>Abstract</title>
Functionally graded materials (FGMs) are advanced class of composite materials which can be used as the thermal barrier to protect inner components from the outside high temperature environment. In FGMs, the volume fraction of each constituent can be tailored made across the thickness for desired applications. In this work, the simulation of FGMs in pipes is considered. Despite the wide application of pipes in machinery, those pipes would suffer from many safety problems, such as thermal stress, cavitation, fracture etc. Application of FGMs to the piping systems could lead to some new solutions accounting for safety measures and higher service life. However, the complex phenomena within the fluid structure interaction are hard to describe with the theoretical solution. The visualization of results from simulation will be helpful in understanding the distribution of kinds of physical quantities within the concerned model. For the simulation, FGMs are modeled as the layered structure in the standard finite element method (FEM) package based on FGM constituent law. The free vibration of the FG pipe is simulated and the accuracy of layered model is verified by numerical calculations. Further, based on the layered model, conjugate heat transfer simulations in a heat exchanger with FGMs are conducted.

DOI： 10.1115/lemp2020-8506

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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 BV  

DOI： 10.1016/j.compstruct.2020.112787

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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 {BV}  

Fluid–structure interaction (FSI) and wave propagation in engineering structures can cause severe damage to piping systems or fluid machines, inducing serious accidents. In these phenomena, the mechanism of structural damage depends on the wave propagation across the fluid–solid interface. Previous studies reported that disagreements between the induced pressure value on the solid–fluid movable interface and the value predicted by the classical one-dimensional theory arose from the effects of two-dimensional wave propagation. To address this problem, in this study, a two-dimensional axisymmetric simulation of wave propagation across the solid-fluid interface with FSI was conducted. The simulation was performed using ANSYS Autodyn with a Lagrangian solver for solids and Eulerian solver for water. The results showed that radial wave propagation caused by the dynamic effect of the tube and water's inertia affected the peak pressure on the solid–fluid interface. The peak pressure was attenuated near the tube wall because of the inertial effect of the tube and fluid expansion. By calculating the mean pressure and axial stress to compare the simulated peak pressure with that from one-dimensional acoustic theory, it was indicated that the transition region for transmitted pressure was located immediately after the solid–fluid interface. In this region, the transmitted peak pressure may exceed the value predicted by one-dimensional acoustic theory. The transition region was oriented in the axial direction from the interface. In addition, prediction of the transmitted peak pressure with one-dimensional acoustic theory was suggested via normal wave speed in the unconfined fluid from a safety engineering perspective, although the circumferential stress generated in the tube enclosing fluid can be sufficiently accurately predicted using the same theory with the Korteweg speed.

DOI： 10.1016/j.ijpvp.2020.104099

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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：Royal Society of Chemistry (RSC)  

<p>Scaling effect of adhesion force at detachment was clarified by a probe-tack test using a glass sphere at mm-scale and an AFM cantilever.</p>

DOI： 10.1039/d0sm00680g

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

We conducted an experimental investigation on the flexural behavior of closed- cell aluminum foam beam under shear stress effect. Three-point bending and flexural vibration tests were carried out and the shear stress effect was generated by changing the specimen’s length. From the bending test, the measured deflection was used to quantify the flexural modulus. From the vibration test, the measured natural frequencies of flexural vibration mode were used to calculate the flexural modulus. The results show that the flexural moduli obtained from both tests agree well. Then, the flexural modulus value was compared with the theoretical value estimated by Timoshenko’s beam theory. As a result, the experimental value was found to be much smaller than the theoretical value when shear stress effect is dominant. Does this mean Timoshenko’s theory cannot describe the flexural behavior of aluminum foam beam? How to fit Timoshenko’s theory with the experimental data is discussed. Moreover, the reason why the flexural modulus was remarkably degraded under shear effect is elaborated.

DOI： 10.1007/s12206-020-0403-1

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/0021998319883418

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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：American Society of Mechanical Engineers (ASME)  

DOI： 10.1115/PVP2020-21535

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1109/JMEMS.2019.2913012

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Multilayer thin films polymer have been commonly used in a wide range of electronics applications, such as solar cells, photoconductors, semiconductors, and light-emitting diodes, in which failure due to delamination can occur. For evaluating and improving the quality of a multilayer thin-film product, the interfacial strength between its layers must be measured correctly and accurately. In this work, the interfacial strength of a multilayer thin-film polymer was quantified by measuring the interfacial energy release rate (interfacial fracture toughness), Gi, using the nanoindentation test technique. Three specimens of four-layer thin films were fabricated on a glass substrate. The top layer of each specimen was prepared with different thicknesses. The unloading curve technique introduced by Kozuki and Kishimoto (2010) was implemented to quantify the Gi of each specimen. Then, cross-sectional observation of the specimens was performed to confirm the layer thicknesses and to identify the delamination condition after the test. The measured Gi tended to increase as the range between the two unloading curves used to calculate the delamination energy widened. This phenomenon is believed to be caused by the plastic energy of the deformed films during the indentation process. Finally, an empirical method for eliminating the effect of the plastic energy on the measured Gi was proposed. Using this method, a pure Gi value can be effectively extracted; thus, the interfacial strength of multilayer thin-film polymers can be measured correctly and accurately.

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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.jfluidstructs.2019.01.017

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掲載種別：研究論文（学術雑誌）  

DOI： 10.18720/MPM.4232019_7

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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：American Society of Mechanical Engineers (ASME)  

DOI： 10.1115/GTINDIA2019-2445

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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：American Society of Mechanical Engineers (ASME)  

DOI： 10.1115/GTINDIA2019-2785

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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/transjsme.18-00137

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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：The Japan Society of Mechanical Engineers  

In turbomachinery, such as turbine, pump, and valve, components damage caused by collapsing cavitation bubbles has been a critical issue that needs a proper solution. For this reason, investigation on the cavitation erosion behavior of materials as well as the life prediction techniques has been extensively conducted. Moreover, a number of repairing techniques, such as by a surface coating of polymeric materials, has been established. However, in real operation, cavitation is actually not the only load acquired by the components. Other external loads, such as centrifugal force and hydraulic pressure, may also affect the generation of damage. Therefore, its effect on the lifetime needs to be considered carefully. In this paper, the behavior of cavitation damage of epoxy resin specimens subjected to uniaxial tensile loading is reported. A self-developed testing device was used to conduct a cavitation test based on ASTM G32 while at the same time exerting a constant uniaxial tensile load to the specimen. Using this device, various levels of tensile stress effect on the cavitation damage was examined. As a result, besides erosion damage, we revealed that the specimens demonstrated fracture when a certain tensile load was applied. Furthermore, as the tensile load was increased, the time to fracture was shortened significantly, indicating the pronounced effect of tensile stress on the damage formation. The crack growth mechanism was then analyzed by fractography. The result indicated that the crack propagation under a mixed condition of cavitation and tensile loads was most likely driven by the combination of creep deformation and fatigue-like crack growth. Finally, a mathematical relationship between tensile stress and cavitation damage life was proposed. The relationship is important to enhancing the existing theory of cavitation damage evaluation in e.g. turbomachinery application.

DOI： 10.1299/mej.17-00151

CiNii Research

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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：一般社団法人 日本機械学会  

<p>A zirconium alloy cylindrical tube exhibited fracture under high-velocity axial impact load when high yield strength pellets were inserted as reported by Morishige et al., 2016. The fracture occurred after a crack was initiated at the tensile side of the bending tube. In this paper, FE analyses were conducted to clarify the fracture mechanism as well as the deformation behavior. At first, axial tensile tests using tubes with four slit-holes located at the center were performed in order to evaluate the fracture behavior of the tube. Then, digital image correlation (DIC) method was utilized to measure the local strain near the slit-holes. The results showed that the fracture displacement became smaller with smaller slit-holes' radius. Also, the strain was concentrated at the slit-holes' tips where cracks were generated before fracture. Subsequently, FE analyses of the tensile tests were conducted by LS-DYNA using the implicit method to obtain the fracture criterion. The load-displacement curve agreed well with the experiment. Then, the relationship between stress triaxiality and equivalent plastic strain near the slit-holes' area were evaluated to define the fracture criterion. Finally, FE analyses of the axial impact tests using the dynamic explicit method were conducted to compare with the fracture criterion defined by the axial tensile tests. The results indicated that a localized stress and strain might occur at the tube boundary adjacent to pellets. This was caused by the interaction between tube and pellets' edge which generated a tensile stress condition at the tube boundary when high yield strength pellet was applied. Under this condition, both stress triaxiality and effective plastic strain could increase and eventually lead to the fracture criterion.</p>

DOI： 10.1299/transjsme.17-00304

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.4035376

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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/s11340-016-0221-7

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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  

DOI： 10.1299/jsmemm.2017.os0525

CiNii Research

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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.compositesa.2016.06.024

Web of Science

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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.5b04705

Web of Science

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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：一般社団法人 日本機械学会  

<p>The dynamic buckling tests using cylindrical tubes with and without internal pellets were carried out to investigate the impact behavior. Various materials of cylindrical tubes and pellets were used to examine the buckling mode and the maximum loads at several impact velocities. In the case of low Young's modulus and low yield strength pellets, the influence of pellets was small because of the small load share of pellets, so the "W" shape of deformation shapes and the maximum impact loads were almost the same of those of empty tubes. On the other hand, the tubes with high Young's modulus and high yield strength pellets indicated different behaviors compared to the empty tubes because of the large load share of pellets. At low impact velocity, pellets with high yield strength caused the strengthening effect and increased the lateral stiffness for tubes. As a result, the pellets led to increase of impact load, decrease of deformation and change of buckling mode to the "S" shape. At high velocity, the strengthening effect of pellets made the tubes stiffer, but led to fracture by the constraint effect of pellets on plastic deformation. The deformation of tubes was compared to Euler's equation, and it was confirmed that the Euler's equation could be applied at the low impact velocity. However, it was not effective for the high velocity impact because of local deformation at the impact side. FEM analyses will be conducted to clarify the deformation shape, maximum load and the mechanism of fracture at high impact velocity as a further study.</p>

DOI： 10.1299/transjsme.16-00194

J-GLOBAL

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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：European Conference on Composite Materials, ECCM  

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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 Society of Mechanical Engineers  

<p>Wetting-induced attraction are widely observed in microstructures where liquid flows along solid surfaces. Unexpected bending or collapse occurs if wetting-induced forces are neglected in the structural design, such as high aspect ratio pillars in the process of wet-etching. In this study, a simple experiment is designed to capture the evolving deformation of a cantilever beam due to capillary flow. A pair of polymer plates fixed at one end with a small gap is submerged into liquid, so that capillary rise between the plates and their attraction can be simultaneously observed. The plate dimension is sub-millimeter scale, which is rather large in observation of capillarity, in order to clearly capture deformation process of the plates until their contacts. Different types of liquids are prepared to investigate the influence of wettability, surface tension, and viscosity. Velocity of capillary flow is also considered by changing submergence rate of the plate. The experimental results of plate deflection are compared to analytical estimation obtained from an equation of motion for capillary rise and an equilibrium between capillary attraction and elastic force of plate. This estimation corresponded well with experimental results regardless of liquid types. In addition, the relationship between plate deflection and material constants is derived in a non-dimensional form. Therefore, plate deformation due to wetting-induced attraction, considering velocity of capillary flow, became predictable only from dimension of plates and material constants.</p>

DOI： 10.1299/mel.16-00227

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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  

Peel test is widely used to evaluate interfacial strength of adhesive tape. The interface strength is usually obtained by subtracting energy consumed for plastic deformation of substrate film from external work for peeling. Deformation of substrate results from interface strength generated in adhesive layer, whose mechanical property is regarded as elastic when substrate is thick enough. It is also convenient to calculate deformation of substrate with assuming elastic behavior of adhesive layer. However, substrates thinner than 100 μm may be affected by viscoelastic property of adhesive layer since thickness of adhesive layer is no longer negligible. It is indispensable to investigate the influence of viscoelastic behavior of adhesive layer on evaluating interface strength of particularly thin adhesive film. In this study, 90° peel test was conducted and the interface strength was evaluated by modifying conventional elastic model to consider viscoelastic behavior of adhesive layer. Stress in adhesive layer caused from displacement of substrate is a function of strain and strain rate, and the corresponding deformation of substrate was computed by finite element method. The shape of substrate deformation was compared with one obtained from conventional elastic model in terms of thickness of substrate and peel speed. The interface strength was also obtained from directly observing peel shape using high speed camera to validate the proposed model. As a result, it was found that the substrate shapes were similar regardless of models when substrate was thick, but proposed model more accurately reflected the influence of peel speed in the thin substrate.

DOI： 10.1299/transjsme.15-00398

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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）  

DOI： 10.1088/1742-6596/656/1/012049

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1177/0021998314521061

Web of Science

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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（国際会議プロシーディングス）  

DOI： 10.1051/epjconf/20159202103

Web of Science

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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：一般社団法人 ターボ機械協会  

Structural repair by polymer coating has been recently attracted attention to pumps in water plants because of its simplicity.The performance of coating material is simply evaluated by cavitation resistance, but it should be considered under loadingcondition for application to existing structures. In this study, damage of coating material due to cavitation is observedwith various loading conditions. Epoxy resin is selected as coating material on aluminum base. First, tensile and shear testsof the coating material is conducted with different way of coating angles to obtain fracture stresses. Second, a conventionalcavitation erosion test is modified using a tensile jig developed to conduct a tension-cavitation test. As a result, the tensioncavitationtest resulted in much severer damage in short time than conventional cavitation erosion test even though the stresson the coating material is more than 10 times smaller than the fracture stresses.

DOI： 10.11458/tsj.42.12_767

CiNii Books

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1080/15421406.2014.968080

Web of Science

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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.supflu.2014.06.023

Web of Science

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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）  

Web of Science

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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：Trans Tech Publications Ltd  

DOI： 10.4028/www.scientific.net/AMM.566.431

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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：Trans Tech Publications Ltd  

DOI： 10.4028/www.scientific.net/AMM.566.50

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1063/1.4816662

Web of Science

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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.ijadhadh.2013.05.005

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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.ijsolstr.2012.10.015

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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）  

DOI： 10.1016/j.jfluidstructs.2012.08.010

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

粘着剤を2種の剥離フィルムで挟まれた構造の基材レス粘着シートは，耐溶剤性，耐熱性に劣るフィルムに，粘着剤のみがシート化され貼り合わせることが出来るため，テレビや携帯電話に代表されるディスプしイを製造する際の偏光板等とガラスを積層するために使用されている。粘着剤と剥離剤を剥離する剥離力は，粘着剤種により変動するため，弾性率を変化させた粘着剤を用いた基材レス粘着シートにおいて，剥離角度や剥離速度の条件を変動させ剥離力を測定した。その結果より，粘着剤と剥離剤の界面の剥離エネルギを解析した。また，剥離角度を変更した条件で剥離先端部の可視化を光学顕微鏡で行うことで，剥離時の粘着剤の変形を観察した。これらの結果を併せることで，粘着剤の弾性率の違いによる剥離のメカニズムを予測した。

DOI： 10.11618/adhesion.48.308

CiNii Books

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その他リンク： https://jlc.jst.go.jp/DN/JALC/10009109505?from=CiNii

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.actamat.2012.02.013

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Scopus

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1017/S1431927612003157

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.11345/nctam.60.249

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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  

A new evaluation method was proposed for the interfacial strength between a thin film and its substrate by nanoindenation test. In this method, the released energy due to a coating delamination is obtained by estimating the shapes of the unloading curve at the points just after and before delamination on the load-displacement curve. Shape of unloading curves can be assumed by obtaining the contact stiffness of thin films. To confirm the validity of the method, nanoindentation tests were conducted for polyimide (PI) coating / Si substrate specimens and the interfacial strength was evaluated. Three specimens that have different thickness were prepared. Contact stiffness of PI film bears a linear relationship with indentation load. Irrespective of the coating thickness, the values of the interfacial strengths converge. In addition, the values of strengths agree with the results obtained by the authors in the previous paper for the case that small scale yielding conditions are satisfied. For the case that indentation loading rate is high and the delamination occurs before the relaxation of film, it is necessary to measure the contact stiffness with each indentation loading rate.

DOI： 10.1299/kikaia.77.629

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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）  

DOI： 10.1017/S0022112010005707

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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.proeng.2011.04.496

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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： 10.4028/www.scientific.net/KEM.462-463.807

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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： 10.1109/ESTC.2010.5642966

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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：The Japan Society of Mechanical Engineers  

A method to evaluate pick-up performance of four kinds of adhesive tape materials with different thickness has been studied numerically and experimentally. Needles peel an IC chip with an adhesive film off the base material in the pick-up process, by pushing the back of the base material. In our evaluation method, the dependence of the peel energy on the peel speed was measured using a peel test. The finite element method was applied to calculate the energy release rate of the pick-up process for various peel lengths. The pick-up time was obtained from the results of the peel tests and the finite element analysis. Our results indicate that the peel energy is the dominant property influencing the pick-up performance, and the difference in energy release rate in the pick-up process between the samples is not significant. Furthermore, the minimum needle displacement was estimated from the calculated pick-up time using our method. The minimum needle displacement of the experimental pick-up values was in good agreement with the estimated result.

DOI： 10.1299/jmmp.4.1051

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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/kikaia.76.730

Scopus

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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：American Institute of Aeronautics and Astronautics Inc.  

DOI： 10.2514/6.2009-1529

Scopus

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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）  

Scopus

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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  

Two-dimensional computations of propagating detonations in a stoichiometric hydrogen-air mixture diluted with nitrogen or argon were perfbrmed using a detailed chemical reaction mechanism Previous computational studies on detonation have not usually considred viscosity. In this study, we considered viscosity and calculated the behavior of shock induced boundary layer. From the results, we estimated the effects of viscosity on the characteristics of detonation. The velocity distributions in the boundary layer were verified by the theory of Sturtevant-Okamura. We investigated the effects of viscosity on cellular structure by examining pressure distribution, and trajectory of triple points.

DOI： 10.1299/jsmemecjo.2009.6.0_13

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1115/1.2956596

Web of Science

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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/s11630-008-0125-7

Web of Science

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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：一般社団法人日本機械学会  

Sand erosion is a phenomenon where solid particles impinging to a wall cause serious mechanical damages to the wall surface. It is well-known that the performance and lifetime of various machines, such as airplane, ship, gas turbine, pump and so on, are severely degraded due to sand erosion. This phenomenon is a typical gas-particle two-phase turbulent flow and a multi-physics problem where the flow field, particle trajectory and wall deformation interact with among others. However, the change of the flow field and the relating particle trajectory during the erosion process have not been taken into account by conventional simulations. This treatment is physically unrealistic. Hence, we have developed the numerical procedure for sand erosion phenomenon, including the temporal change of the flow field and the wall shape. In this work, we simulate sand erosion of 90 degree bend with a square cross-section. The bend erosion is typical target of sand erosion experiments and is useful for verification of numerical simulations. The numerical results are compared with experimental data, and it is confirmed that the developed code can capture the sand erosion phenomena reasonably.

DOI： 10.1299/kikaib.74.1478

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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：一般社団法人日本機械学会  

We have investigated jet engines, in which hydrogen fuel is injected from turbine blade surface and combusted within turbine blade passages. Although these hydrogen-fueled propulsion systems are expected to have higher power, lighter weight and lower emissions, it still has many problems to be solved. In the previous studies, it was found that blade surface temperature exceeds the allowable temperature limit. Therefore, it is necessary to investigate the flow field with hydrogen combustion and the cooling method which prevents structure materials from melting down. The objective of this study is to clarify the influence of the injector-hole layout on the characteristics of the 3-dimensional flow field with hydrogen-fueled combustion within a turbine blade passage. Reynolds-averaged compressible Navier-Stokes equations are solved with incorporating a turbulence and a reduced chemical mechanism models. Using the computational results, the 3-dimensional turbulent flow field with chemical reactions is visualized and investigated. Additionally, the film cooling effect and the aerodynamic performance of the blade are estimated.

DOI： 10.1299/kikaib.74.2244

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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：一般社団法人日本機械学会  

Because of NO_x, SO_x and CO_2 exhausted by fossil-fuel combustion, air pollution is one of critical issues in our environment. To overcome these environmental problems, we have investigated jet engines, in which hydrogen fuel is injected from turbine blade surface and combusted within turbine blade passages. In the previous studies, endwall effects on the turbine performance have not been considered. However, it is expected that secondary flows due to the endwall have substantial effects on the engine performance. Therefore, it is necessary to clarify the influence of the endwall on the characteristics of the 3-dimensional flow field with hydrogen-fueled combustion. Reynolds-averaged compressible Navier-Stokes equations are solved with incorporating a turbulence and a reduced chemical mechanism models. Using the computational results, the engine performance is evaluated from the standpoints of combustor and turbine.

DOI： 10.1299/kikaib.74.2252

CiNii Books

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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）  

Scopus

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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）  

Scopus

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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）  

Web of Science

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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  

Granulation is generally performed in stirred vessel to spray binder into row material and to stir particles. However, the conventional granulating system has some problems. First, there are 2 peaks in the particle diameter distribution that may degrade the quality of products. Second, it takes too long time to determine the operating conditions for desired particle diameter distributions. Therefore, it is required for us to highly control granulation process in stirred vessel with computer simulations. In the present study, we perform numerical experiments of granulation process in stirred vessel to clarify the reason why 2 peaks in the particle diameter distribution appear.

DOI： 10.1299/jsmemecjo.2007.7.0_149

CiNii Books

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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：日本語  

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記述言語：英語   掲載種別：学位論文（博士）  

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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：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：火薬学会  

CiNii Books

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記述言語：英語  

Web of Science

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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  

Dissimilar material joint makes a machine light and efficient. Welding is widely used to connect dissimilar materials, but an intermetallic compound produced in the interface and stress specificity at interface end are concerned to decrease the joint strength. It is important to evaluate the strength of welded joint for designing machine and structure. In this study, single lap specimens with welding joint of Fe and Al plates were prepared for a tensile shear test and a fatigue test. Joint strength and interfacial strength were investigated by modifying shape of welding joint. Fracture analysis revealed the interface was brittleness destruction and the joint strength depends on the strength of the starting point of the destruction. Fatigue curve can be classified every destruction form by using the hotspot stress of the starting point of the destruction.

CiNii Books

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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  

Water hammer is familiar phenomena in our life while this phenomena causes noises and failures of water plumbing. Previous studies of water hammer revealed that wave speeds were well predicted by a simple theory and pressure surges could be estimated with the speeds by experiments, numerical analysis, and analytic methods. However, the frontal wave shape of water hammer was neglected and its propagation mechanism was not discussed in the simplified theories. This study focus on the frontal mechanism to understand the structure and decrease the damage of the water hammer. In the present study, we visualize the frontal structures in experiments and numerical analysis as well as revealing strain signals of coupled tubes with pressure waves.

CiNii Books

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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  

Fluid-structure interaction is one of the most important phenomena to be clarified and controlled in many industrial fields. In some problems, interaction mechanism strongly depends on wave propagation across the interface of solid and fluid. Although many studies have been conducted about fluid-structure interaction, the mechanism of wave propagation across to the solid-fluid interface remains unclear. In this study, we investigated the effect of surface conditions such as surface roughness and wettability of solid materials to wave propagation across the interface. The results of the experiments indicated that due to the wettability of the solid surface, the intensity of the cavitation which appeared near the interface was changed and theoretical assumption of the interface continuity may not be valid under some conditions.

CiNii Books

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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  

When cavitation occurs and bubbles collapses in fluid machinery, such as pumps, impact loading due to the bubble collapsing shortens the life time and decreases the performance. Recently, inspection of cavitation-erosion damage inside the pumps has been conducted by direct visual observations after stopping the operation temporarily. In this study, to realize damage monitoring remotely from outside of the machinery, impact load by spark-generated bubble collapse was estimated using inverse analysis. Impact experiments by spark-generated bubbles were conducted with aluminum plate and impact load and point were measured with AE sensors. The effect of impact point in measurement of impact load was confirmed by bubble collapses at different impact points.

CiNii Books

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記述言語：英語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

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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 the field of steelmaking and refining, phosphorus is impurities. The steel is produced by removing reacted with slug to it. Improving the reaction speed of phosphorus contribute significantly to the reduction of steel making process and it can achievement by increase interfacial area between slug and metal. So the purpose of this research is to increase interfacial area efficiently by electromagnetic force (EMF) instead of inert gas. It revealed that it is possible to sloshing of the liquid metal by electromagnetic force in horizontal directions by numerical simulation and increasing the interfacial area during sloshing. Performs approximate analysis by linear theory for horizontal sloshing of the multiliquid-layer and compered with the numerical value. In addition, new vertical sloshing method that is locally applied electric field and magnetic field is devised.

CiNii Books

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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  

Nonmagnetic fluid can be levitated if a very strong magnetic field is applied by a super-conducting magnet. This study suggests noncontact magnetic virtual channel (MVC) in the casting process of nonconductive materials such as glasses to enable the continuous casting in high quality. In this study, we model the MVC by using a magnetic fluid in a weak magnetic field. A rectangular coil is assumed as a source of the magnetic power. The magnetic field distribution of the rectangular coil was calculated and the distribution of the magnetic force is obtained. To confirm whether a liquid column is stable or not, stability analysis is carried out about a liquid film held by magnetic power. As a result, stability is confirmed and further analysis about the floating position and the cross sectional shape of the floating liquid is done. An experiment to let a nonmagnetic fluid float in magnetic fluid was conducted. Tests were done with distilled water and silicone oil and both liquids can be levitated. Observation suggests that the shape of the floating liquids vary according to the boundary tension. Therefore, this accords with the analysis results qualitatively.

CiNii Books

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記述言語：英語  

DOI： 10.1115/PVP2015-45752

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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  

Abstract A cerebral aneurysm is a disease in which part of the artery in the brain is enlarged in nodular and causes a subarachnoid hemorrhage when the aneurysm is ruptured. It brings pain to people and death. In this study, in order to compare the stress at the branch in the development process of the aneurysm, numerical simulation was performed using the aneurysm growth model. In the model without aneurysm, large circumferential stress and pressure were acting on the center of the branch. In the aneurysm growth model, the circumferential stress of about 1.5 times of a case without aneurysm was acting upon base of the aneurysm. Therefore we thought the local distention may be involved in the growth and development of cerebral aneurysm. Moreover, it must be necessary to investigate the growth and rupture mechanism of cerebral aneurysm by the simulation using the model of the large aneurysm under the various conditions of the branch vessel diameter ratio and branch angle.

CiNii Books

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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  

Welding is widely used to connect dissimilar materials, but an intermetallic compound produced in the interface is concerned to decrease the joint strength. It is important to evaluate the strength of welded joint for designing machine and structure. In this study, single lap specimens with welding joint of Fe and Al plates were prepared for a tensile shear test and a fatigue test. Influence of rotation caused by tension and distribution of interfacial strength were investigated by modifying specimen length, number of tabs, and shape of welding joint. It was found that the rotation did not have significant influence on interfacial strength, but fracture behavior varied and indicated uneven strength distribution along interface.

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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  

Capillary induced forces are widely observed in fine structures where liquid flows along solid surfaces, such as wet-etching process in micro/nano-pillar fabrication. Undesirable bending or collapse of the structure occurs if they are improperly considered in the structural design. In this study, liquid column formation between aligned polymer plates is observed and the resulting capillary induced force causing the plate deformation is evaluated. The plate dimension is sub-millimeter scale, which is rather large in observation of capillarity, in order to clearly measure deformation process of the aligned plates until their contacts. When the plates are immersed into liquid from the fixed end, gap between plates becomes smaller due to liquid columns formed far from the end. It is found that the deformation of the plates proceeds more unstably as the number of plates increase, but their contact is initiated at the similar plate length into liquid.

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記述言語：日本語   掲載種別：記事・総説・解説・論説等（学術雑誌）   出版者・発行元：一般社団法人 日本接着学会  

DOI： 10.11618/adhesion.50.235

CiNii Books

J-GLOBAL

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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  

Water hammer occurs in a pipe when water flow is suddenly stopped. There are pipes having the square or rectangular cross sectional shape rather than the circular shape: micro channel, gutter, and so on. Moreover, a part of the walls is often composed by different material or different wall thickness. To reveal pressure wave propagation in such a channel, we examined water hammer phenomenon and measured wave speeds in rectangular tubes with different wall materials and thicknesses. We newly proposed theoretical wave speeds based on the classical theory and the junction conditions of two walls: fixed, simply supported, and mixed. We confirmed that theoretical predictions agreed with experimental wave speeds.

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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  

A tack is important physical property for pressure-sensitive adhesive that shows instantaneous adhesiveness. Recently, thinner adhesive has been developed and often applied in industry while the occurrence and the mechanism of the tack have not been clarified yet. It is known that as adhesive is thinner than 5μm, the tack becomes much weaker. To improve and develop the thin but strong adhesive it is necessary to observe the peeling phenomena of the adhesive. In this study, the aim is to investigate the effect of the adhesive's thickness on peeling behaviors and tack strengths with probe tack tests. We confirmed that as adhesive is thicker, peel force becomes larger but the rate of increase of peel force becomes lower and the amount of adhesive deformation becomes larger. We observed the displacement of fine particles mixed in adhesive. As result, as the particles reaches deeply from the surface of the adhesive to its inside, the displacement of the particles becomes smaller and the movement of the particles isn't seen at 25 μm from the surface.

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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 a design of fine structures, characteristic phenomena such as surface forces, which are usually negligible in a macroscopic scale, need to be taken into consideration. When a liquid exists between solid surfaces, a liquid column can form in accordance with the balance of their surface energies, called capillarity. In this study, deformation induced by capillarity is quantitatively evaluated. A pair of polymer plates fixed at one end and immersed in liquid, bends because of capillary forces from a liquid column formed between the plates. Although capillary-induced deformation is usually observed at the micro/nano scales, the dimensions of the prepared plate specimens are on the order of millimeters because the larger scale makes observation of the evolving deformation easier. Experimental results indicate that bending proceeds to either contact or collapse the plates if their gap spacing becomes smaller than 2/3 of the initial plate separation, regardless of plate dimensions. This phenomenon is theoretically validated by proposing a dimensionless number, which is derived from a balance of surface energy, potential energy of a liquid, and strain energy of a plate.

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記述言語：日本語   出版者・発行元：日本フルードパワーシステム学会  

CiNii Books

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J-GLOBAL

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J-GLOBAL

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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  

Structural interaction between solids and liquids are seen in various industrial fields, such as MEMS fabrication. A droplet between solid surfaces forms a liquid bridge, which provides a resistive or a desorption force due to surface tension. These forces can be ignored in large scale structures, but they show significant influence in micro scale. Since the deformation caused by liquid bridge has not been sufficiently studied, it is necessary to quantitatively evaluate these forces. In this study, two pillars that were aligned in parallel were prepared and the deformation caused by a liquid bridge was observed with different types of liquid. It is confirmed that the spacing between two pillars were getting closer and eventually attached with each other when silicone oil was used as liquid. But water did not cause any change in two pillars. The evaluation of the pillar deformation was conducted using a cantilever model, considering Laplace pressure and surface tension as drive forces. As a result, it was found that Laplace pressure has more significant influence than surface tension.

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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 use of thin-film technology has rapidly expanded. Multilayer structures composed of thin film with specific properties are used in many fields, for example liquid crystal displays and solar cells. In a multi-layer structure, the interface between films has the lowest strength, thus the interface strength between film and adhesive is important for designing products and improving interface strength. Peeling test is used widely as a method to measure the interface strength. In that test, stick-slip phenomenon sometimes occurs in particular conditions, and it is difficult to evaluate the interface strength if that happens. Therefore the research about stick-slip behavior in peeling test is important to establish the method measuring the interface strength appropriately. This paper focuses on the relation between adherend stiffness and stick-slip phenomenon, and clarifies the effect of adherend stiffness on stick-slip phenomenon.

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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  

Repair composites has high stiffness and flexible workability. Therefore, they have been used as efficient repair material for surface damages including cracks and erosions. Catalog parameters such as stiffness, water resistance, chemical resistance, and delamination strength. However, catalog delamination strength for lining-application has not been well clarified. In this study, we examined tensile test using particle-reinforced composite material bonded on tensile test pieces. Delamination strength was evaluated by nominal strain and effect of material and surface condition of tensile specimen.

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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  

Structural members of automobiles are required to improve collision safety and reduce weight for the purpose of lower fuel consumption. Therefore a thin-walled cylinder which has excellent energy absorption efficiency and lightweight is used for the shock absorber of structural members. This cylinder absorbs impact energy in the continuous plastic buckling distortion caused by axial impact loading. However the load histories of the axial crushing of the cylinder repeat the periodic variation with the local buckling. That is causing the decrease of energy absorption efficiency. For this reason, the design which suppresses variation of load lead to improved energy absorption efficiency. The purpose of this study is to develop members improved the stability of load. We examined the optimal cross-sectional shape of the cylinder to reduce the load variation with FEM analysis.

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記述言語：日本語   出版者・発行元：日本工業出版  

CiNii Books

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記述言語：英語  

Web of Science

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記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

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記述言語：英語  

Web of Science

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記述言語：英語  

Web of Science

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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  

Particle reinforced plastics (PRP) have highly stiffness and flexible workability. Therefore, they were widely used as efficient repair material for damages including cracks and erosions. However, delamination behavior and strength of lining-applied PRP have not been clarified. In this study, we examined tensile test using particle-reinforced resin material bonded on 2 types of tensile test pieces; one is made by polycarbonate as transparent material to observe delamination behavior, and the other is made by SUS304 to evaluate delamination strength for practical use. Each test was carried out with tension rate of 1.0 mm/min and strains of PRP, PC and SUS304 were measured by strain Gages. As the result of PRP bonded on PC tensile test piece, relationship between delamination behavior and strain was clarified. At first, delamination of PRP started and gradually propagated with increasing strain of PRP. After that, steep delamination occurred and strain of PRP steeply decreased. The result indicated that steep delamination of PRP can be determined by its strain. In the result of PRP bonded on SUS304 tensile test piece, steep delamination could be also observed as steep decrease of PRP strain. Strains of tensile test pieces at steep delamination for PC and SUS304 were different; strain of PC tensile test piece at steep delamination was higher than strain at 0.2 proof stress of PRP. Strain of SUS304 tensile test piece was smaller than that at 0.2 proof stress of PRP.

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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：荏原製作所  

CiNii Books

CiNii Research

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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  

For the design of mechanical structures, the fatigue limit is indispensable. Therefore, it has been developed the simple evaluation method with thermography. In this method, the temperature change can be measured for the specimen under cyclic load, and the fatigue limit is corresponding to the inflection point the temperature starts to rise rapidly. This method has been studied widely, the thermography system is used the lock-in type thermography which synchronize the signal with the cyclic load. However, it has a problem that the equipment is expensive. In this study, we performed the estimation of fatigue limit by using the non-lock-in type thermography for rotate bending fatigue testing, in particular, examines the following three points, i) the validity of applying the non-lock-in type thermography for rotate bending fatigue test, ii) determination of the inflection point in the stress-temperature change curve, iii) relationship between temperature and time.

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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  

Recently, PSA(Pressure Sensitive Adhesive) is applied in various industrial conducts products. "Nakiwakare" is knoi as the serious problem that a peeling interface of PSA moves to the opposite one. We conducted the peeling tests in various conditions with the multi axes driven test machine to fmd out the peeling conditions in which Nakiwakare occurred. Additionally, we evaluated the interfacial strength of PSA through the peel tests. We found that there were 2 patterns of Nakiwakare-one in the case of the high-speed and high-angle, and the other in the very low-speed peeling.

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記述言語：英語  

DOI： 10.1115/1.4000510

Web of Science

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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 goal of the present study is to reveal the coupling of large-amplitude (including plastic deformation) flexural waves and precursor waves in water-filled, thin-wall tubes. The flexural waves are generated by stress waves in the water propagating along the tube axis. The maximum hoop strain with mild-steel tubes was observed just below the bottom surface of the buffer as a bulge with 25% hoop strain. Hoop and longitudinal strains indicate a steep elastic front followed by a gradual plastic deformation. Since the plastic deformation wave travels much slower than the elastic waves, the initial flexural wave fronts propagate at 1350 m/s and are close to the wave speed of the Korteweg's elastic theory of water hammer. Measured wave speeds with CFRP tubes are consistent with effective modulus models of layered composite materials. The failure mechanisms of the CFRP tube wound at 45° resemble that of ductile materials, whereas the mechanisms for the tubes wound at 60° resemble those of brittle materials.

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記述言語：英語  

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記述言語：英語   出版者・発行元：Dynamic Failure of Materials and Structures  

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記述言語：英語  

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記述言語：英語  

DOI： 10.1007/s11630-008-0186-7

Web of Science

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記述言語：日本語   出版者・発行元：公益社団法人日本ガスタービン学会  

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出版者・発行元：Japan Society of Mechanical Engineers  

DOI： 10.1299/jfst.3.868

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記述言語：英語  

DOI： 10.1299/jfst.3.868

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記述言語：英語   掲載種別：速報，短報，研究ノート等（学術雑誌）   出版者・発行元：American Institute of Aeronautics and Astronautics Inc.  

DOI： 10.2514/1.BB7997R

Scopus

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記述言語：英語  

DOI： 10.2514/1.21223

Web of Science

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記述言語：英語  

DOI： 10.2514/1.21223

Web of Science

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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  

CiNii Books

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記述言語：英語  

Web of Science

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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  

Granulation is generally performed in a stirred vessel, by spraying binders onto row materials stirring the particles. However, the conventional granulation system has some problems. First, there are double peaks in the particle diameter distribution that degrade the quality of final products. Second, it takes too long time to determine the operating and producing conditions for a desired particle diameter distribution. Therefore, it is required for us to sophisticatedly control a granulation process in a stirred vessel with aid of computer simulations. In the present study, we carry out numerical experiments of granulation processes in a simplified stirred vessel to clarify the reason why double peaks in the particle diameter distribution appear. Through the study, it is confirmed that the particle diameter distribution approaches to an asymptotic state at the final stage of granulation, and the double peaks are generated by the statistical destruction of large particles.

DOI： 10.1299/kikaib.73.2403

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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：一般社団法人日本機械学会  

The purpose of this paper is to explore an explanation of detonation soot track formation, comparing with previous speculations of formation mechanism. Focusing on the role of shear stress in transporting soot along the surface, we investigated the non-reactive Mach reflections numerically with three-dimensional compressible Navier-Stokes simulations. Numerical results are compared with a two-dimensional detonation simulation and used to investigate the effect of shear stress spatial and temporal variations on soot redistributions. The motions of soot due to surface shear stress are numerically examined with treating soot as both particles and fluid parcel.

CiNii Books

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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  

CiNii Books

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記述言語：英語  

DOI： 10.1007/s11630-006-0233-1

Web of Science

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記述言語：日本語   出版者・発行元：日本流体力学会  

Although hydrogen-fueled propulsion system is expected to have higher power, lighter weight and lower emissions, it still has many problems to be solved. We have investigated jet engines with hydrogen-fueled combustion within a turbine blade passage. From past studies, it is necessary to investigate the flow field with hydrogen combustion and the cooling method which prevents structure materials from breaking down. The objective of this study is to clarify the influence of the injector-hole layout on the properties of the 3-dimensional flow field with hydrogen-fueled combustion within a turbine blade passage. Reynolds-averaged compressible Navier-Stokes equations are solved with incorporating a turbulence and a reduced chemical mechanism models. Using the computational results, the 3-dimensional turbulent flow field with chemical reactions is numerically visualized.

CiNii Books

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記述言語：日本語   出版者・発行元：日本流体力学会  

The effects of surface roughness are very important in multi-physics simulations. Since the availability of existing models is limited under a certain roughness conditions, it is needed to develop a more universal turbulence model to calculate various types of surface roughness. In the present study, we propose a more universal turbulence model for a rough wall. The model function is determined for the 2D boundary layers over square-cross-section ribs with different pitches. Next, the model is verified to 2D boundary layers with uniformly distributed roughness and NACA4412 single airfoil with different attack angles. It is confirmed that the present model can capture the roughness effects reasonably.

CiNii Books

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記述言語：英語  

Web of Science

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記述言語：英語  

DOI： 10.2322/tjsass.47.249

Scopus

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記述言語：英語  

DOI： 10.2322/tjsass.47.249

Web of Science

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記述言語：日本語   出版者・発行元：日本流体力学会  

The present study focuses on a straight-through-flow type labyrinth seal to decrease leakage flow rate, which is commonly used in a current gas turbine. First, the labyrinth shape is optimized with a gradient method. Investigating the numerical results for the flow fields in the optimized and the non-optimized shapes, the reason why the pressure drop increases is numerically clarified. Second, the effect of axis rotation is investigated. Finally, based on the insights obtained from the computations, a more desirable labyrinth seal configuration is proposed, and the performance is numerically verified. The numerical results confirmed that the newly proposed seal has the best performance to suppress the leakage flow rate.

CiNii Books

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記述言語：英語  

DOI： 10.2514/1.976

Web of Science

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記述言語：英語  

DOI： 10.2514/1.976

Web of Science

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