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Journal of Thermal Science 2017年第2期26卷 113-118页

作者： kazuhiko toshimitsu Takahiko Narihara Hironori Kikugawa Arata Akiyoshi Yuuya Kawazu Dept.of Information and Systems Engineering Faculty of Information EngineeringFukuoka Institute of Technology3-30-1 Wajiro-higashiHigashi-kuFukuoka 811-0295Japan Dept.of Energy and Environmental Engineering Interdisciplinary Graduate School of Engineering SciencesKyushu University Dept.of Mechanical Engineering Oita National College of Technology IHI Corporation Mechanical-Environmental System Engineering Major Oita National College of Technology

The effects of turbulent intensity and vortex scale of simulated natural wind on performance of a horizontal axis wind turbine(HAWT) are mainly investigated in this paper. In particular, the unsteadiness and turbulence of wind in Japan are stronger than ones in Europe and North America in general. Hence, Japanese engineers should take account of the velocity unsteadiness of natural wind at installed open-air location to design a higher performance wind turbine. Using the originally designed five wind turbines on the basis of NACA and MEL blades, the dependencies of the wind frequency and vortex scale of the simulated natural wind are presented. As the results, the power coefficient of the newly designed MEL3-type rotor in the simulated natural wind is 130% larger than one in steady wind.

关键词： Wind Turbine Wind Energy Natural Wind Unsteady Flow Rotor Design Turbulence

PIV Measurements of Flows around the Wind Turbines with a Flanged-Diffuser Shroud

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Journal of Thermal Science 2008年第4期17卷 375-380页

作者： kazuhiko toshimitsu Koutarou Nishikawa Wataru Haruki Shinichi Oono Manabu Takao Yuji Ohya Dept.of Mechanical Engineering Oita National College of Technology Kawasaki Precision Machinery Ltd. Honda Motor Co. Ltd. Machine & Electronics Co. Ltd. Dept.of Mechanical Engineering Matsue National Collage of Technology Research Institute of Applied Mechanics Kyushu University

The wind turbines with a flanged-diffuser shroud -so called ＂wind lens turbine＂- are developed as one of high performance wind turbines by Ohya et al. In order to investigate the flow characteristics and flow acceleration, the paper presents the flow velocity measurements of a long-type and a compact-type wind turbines with a flanged-diffuser shroud by particle image velocimetry. In the case of the long type wind turbine, the velocity vec- tors of the inner flow field of the diffuser for turbine blades rotating and no blades rotating are presented at Rey- nolds number, 0.9x105. Fur^thermore the flow fields between with and without rotating are compared. Through the PIV measurement results, one can realize that the turbine blades rotating affects as suppress the disturbance and the flow separation near the inner wall of the diffuser. The time average velocity vectors are made on the av- erage of the instantaneous velocity data. There are two large vortices in downstream region of the diffuser. One vortex behind the flange acts as suck in wind to the diffuser and raise the inlet flow velocity. Another large vortex appears in downstream. It might be act as blockage vortex of main flow. The large blockage vortex is not clear in the instantaneous velocity vectors, however it exists clearly in the time average flow field. The flow field around the wind turbine with a compact-type flanged-diffuser shroud is also investigated. The flow pattern behind the flange of the compact-type turbine is the same as the long-type one. It means that the effect of flow acceleration is caused by the unsteady vortices behind the flange. The comparison with CFD and PIV results of meridional time-average streamlines after the compact-type diffuser is also presented.

关键词： wind turbine PIV wind energy flanged diffuser flow visualization

Improvement of a Propulsion Equipment with a Supersonic Nozzle for Single Pulse Detonation

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Open Journal of Fluid Dynamics 2014年第5期4卷 447-453页

作者： kazuhiko toshimitsu Shuuto Mikajiri Ryo Takahashi Department of Mechanical Engineering Oita National College of Technology Oita Japan Mechanical-Environmental System Engineering Major Oita National College of Technology Oita Japan Department of Computer Science and System Engineering Kyushu Institute of Technology Kitakyushu Japan

A pulse detonation engine (PDE) is one of candidates of aerospace engines for supersonic cruse. In the paper, a supersonic nozzle ejector is designed to increase thrust of single pulse detonation for methane-oxygen and hydrogen-oxygen mixtures. The design method is based on the conventional characteristic method and inlet condition is averaged value of detonations of methane-oxygen and hydrogen-oxygen mixtures. Comparison of thrusts with a design nozzle and no nozzle (straight- type) is conducted to ensure the designed nozzle performance. Furthermore, the flow velocity, temperature and velocity of the designed nozzle are calculated to ensure its appropriateness with the commercial software ANSYS CFX. Consequently, we succeed in increasing the thrusts of the single pulse detonation with the nozzle, which are 1.4 and 2.0 times as large as ones of straight- type for methane-oxygen and hydrogen-oxygen mixtures respectively.

关键词： Thruster Detonation Impulse Supersonic Flow Method of Characteristics CFD Nozzle

A Low-Cost Active Control Multi-Fan Turbulence Wind Tunnel with an Embedded System to Generate Natural Wind

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Open Journal of Fluid Dynamics 2019年第2期9卷 158-167页

作者： Haruka Kikuchi Hiroyuki Matsubara Parnravee Pornthisarn kazuhiko toshimitsu Department of Information and Systems Engineering Fukuoka Institute of Technology Fukuoka Japan

This paper describes a new actively controlled multi-fan wind tunnel that generates natural wind as a type of turbulence wind tunnel at a reduced cost. The driving section of the wind tunnel has 100 PC cooling fans that are controlled by an original embedded system. The fluctuating velocity wind is successfully generated with a mean velocity of 7 m/s and two turbulent intensities of 2% and 3% based on Karman’s power spectrum density function. The case of 2% has the integral scales of 5 m, 10m and 20 m, and the case of 3% has the integral scales of 3 m, 6 m and 15 m with a turbulence grid. In particular, the wind with the turbulent intensity of 2% satisfies the Kolmogorov’s -5/3 multiplication rule of inertial subrange with the frequency range from 0.01 Hz to 2.0 Hz. Consequently, the new wind tunnel can be used for studying engineering technology and research regarding conditions with natural wind.

关键词： Wind Tunnel Natural Wind Flow Control Embedded System Turbulence Wind Turbine

Experimental Investigation of Performance of the Wind Turbine with the Flanged-Diffuser Shroud in Sinusoidally Oscillating and Fluctuating Velocity Flows

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Open Journal of Fluid Dynamics 2012年第4期2卷 215-221页

作者： kazuhiko toshimitsu Hironori Kikugawa Kohei Sato Takuya Sato Department of Mechanical Engineering Kyushu University Fukuoka Japan Department of Mechanical Engineering Oita National College of Technology Oita Japan

The wind turbine with a flanged-diffuser shroud—so called “wind-lens turbine”—is developed as one of high performance wind turbines by Ohya et al. In this paper, the wind turbine performance is investigated for both steady and unsteady winds. The compact-type wind lens turbine shows higher efficiency than the only rotor wind turbine. Also, the flow structure around the compact-type wind turbine is made clear by CFD and PIV in steady wind. Furthermore, the performances of the only rotor and the compact-type wind-lens turbines for unsteady wind are experimentally and numerically investigated. Experimental and numerical results are presented to demonstrate the dependence of frequency of the harmonic oscillating velocity wind on power coefficient. Consequently, the compact-type wind-lens turbine show better performance than the only rotor one in sinusoidally oscillating velocity wind. Furthermore, the numerical estimation can predict the power coefficient in the oscillating flows to an accuracy of 94% to 102%. In addition, the dependence of the turbine performance on turbulent intensity and vortex scale of natural fluctuating wind is presented.

关键词： Wind Turbine Unsteady Flow Wind Energy Power Coefficients Flanged Diffuser Natural Wind

Progress in particle-beam-driven inertial fusion research: Activities in Japan

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Matter and Radiation at Extremes 2018年第1期3卷 12-27页

作者： kazuhiko Horioka Department of Energy Sciences Tokyo Institute of TechnologyNagatsuta 4259Yokohama 226-8502Japan

Research activities in Japan relevant to particle beam inertial fusion are briefly *** activities can be ascended to the *** the past three decades,significant progress in particle beam fusion,pulsed power systems,accelerator schemes for intense beams,target physics,and high-energy-density physics research has been made by a number of research groups at universities and accelerator facilities in ***-flux ions have been extracted from laser ablation *** of the ion velocity distribution in the plasma by an axial magnetic and/or electric field has realized a stable high-flux low-emittance beam *** dynamics have been studied both theoretically and *** efforts have been concentrated on the beam behavior during the final compression stage of intense beam accelerators.A novel accelerator scheme based on a repetitive induction modulator has been proposed as a cost-effective particle-beam driver ***-plasma interaction and pulse-powered plasma experiments have been investigated as relevant studies of particle beam inertial *** irradiation method to mitigate the instability in imploding target has been proposed using oscillating heavy-ion *** new irradiation method has reopened the exploration of direct drive scheme of particle beam fusion.

关键词： Particle beam Inertial confinement fusion Pulse power Heavy ion Laser ion source Beam dynamics Final bunching Induction synchrotron High energy density Warm dense matter

Rebamipide promotes healing of colonic ulceration through enhanced epithelial restitution

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World Journal of Gastroenterology 2011年第33期17卷 3802-3809页

作者： Tomohisa Takagi Yuji Naito kazuhiko Uchiyama toshimitsu Okuda Katsura Mizushima Takahiro Suzuki Osamu Handa Takeshi Ishikawa Nobuaki Yagi Satoshi Kokura Hiroshi Ichikawa Toshikazu Yoshikawa Department of Molecular Gastroenterology and Hepatology Graduate School of Medical ScienceKyoto Prefectural University of Medicine6028566 KyotoJapan

AIM:To investigate the efficacy of rebamipide in a rat model of colitis and restitution of intestinal epithelial cells in ***:Acute colitis was induced with trinitrobenzene sulfonic acid(TNBS)in male Wistar *** received intrarectal rebamipide treatment daily starting on day 7 and were sacrificed on day 14 after TNBS *** distal colon was removed to evaluate the various parameters of ***,wound healing assays were used to determine the enhanced restitution of rat intestinal epithelial(RIE)cells treated with ***:Intracolonic administration of rebamipide accelerated TNBSinduced ulcer *** in the wet weight of the colon after TNBS administration were significantly inhibited by *** wound assay revealed that rebamipide enhanced the migration of RIE cells through phosphorylation of extracellular signalregulated kinase(ERK)and activation of Rho ***:Rebamipide enema healed intestinal injury by enhancing restitution of RIE cells,via ERK *** might be a novel therapeutic approach for inflammatory bowel disease.

关键词： Rebamipide Experimental colitis Intestinal epithelial cells Extracellular signalregulated kinase Rho kinase

HYBRID FINITE ANALYTIC SOLUTION FOR THREE-DIMENSIONAL TIDAL FLOW WITH SIGMA COORDINATE SYSTEM

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Journal of Hydrodynamics 2000年第2期12卷 54-61页

作者： Huai, Wenxin toshimitsu, Komatsu Li, Wei Wuhan Univ of Hydraulic and Electric Engineering Wuhan China

A three-dimensional numerical model was developed to predict the behavior of tidal flow by using the σ-coordinate transformation. Conservation equations were solved by hybrid finite analytical techniques. The hydrodynamic model was verified with the analytical solutions for the tidal forcing in an open channel. The simulation results are in good agreement with the analytical solutions.

关键词： Computer simulation Hydrodynamics Mathematical transformations Models Numerical methods Three dimensional

Oxygens matter in the bilayer nickelate superconductor

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 177-178页

作者： kazuhiko Kuroki Department of Physics Graduate School of ScienceOsaka UniversityOsaka 560-0043Japan

The recent discovery of high T_(c) superconductivity under pressure in a bilayer Ruddlesden-Popper-type nickelate La_(3)Ni_(2)O_(7)[1] has attracted great interest both experimentally and ***,following this discovery,superconductivity in a trilayer nickelate La_(4)Ni_(3)O_(10) has also been discovered[2,3].These findings have confirmed the arrival of the nickel age of superconductivity[4],kicked off by the discovery of superconductivity in the thin films of infinite layer nickelates[5].

关键词： superconductivity nickel superconductor

Full-scale dynamic testing of response-controlled buildings and their components:concepts,methods,and findings

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Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 167-181页

作者： kazuhiko Kasai Kazuhiro Matsuda Structural Engineering Research Center Tokyo Institute of Technology Director and Professor Assistant Professor

A series of shake-table tests was conducted by inserting and replacing 4 different types of dampers,or by removing them in a full-scale 5-story steel frame building. The objective is to validate response-control technologies that are increasingly adopted for major Japanese buildings without being attested to-date by a major earthquake. Test results are briefly described,and good performance of the dampers and frame demonstrated. The concepts of the full-scale building tests and various contributions are discussed. The difficulty associated with full-scale dynamic testing is explained.

关键词： response-controlled building steel frame steel damper viscous damper oil damper viscoelastic damper