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Influences of Incidence Angle on 2D-Flow and Secondary Flow Structure in Ultra-Highly Loaded Turbine Cascade

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Journal of Thermal Science 2014年第1期23卷 13-21页

作者： Hoshio Tsujita atsumasa yamamoto Department of Mechanical Engineering Hosei University3-7-2Kajino-choKoganei-shiTokyo Japan

An increase of turbine blade loading can reduce the numbers of blade and stage of gas turbines. However, an increase of blade loading makes the secondary flow much stronger because of the steep pitch-wise pressure gradient in the cascade passage, and consequently deteriorates the turbine efficiency. In this study, the computations were performed for the flow in an ultra-highly loaded turbine cascade with high turning angle in order to clarify the effects of the incidence angle on the two dimensional flow and the secondary flow in the cascade passage, which cause the profile loss and the secondary loss, respectively. The computed results showed good agreement with the experimental surface oil flow visualizations and the blade surface static pressure at mid-span of the blade. The profile loss was strongly increased by the increase of incidence angle especially in the positive range. Moreover, the positive incidences not only strengthened the horseshoe vortex and the passage vortex but also induced a new vortex on the end-wall. Moreover, the newly formed vortex influenced the formation of the pressure side leg of horseshoe vortex.

关键词： Turbine Cascade Incidence Angle Numerical Analysis Secondary Flow

Numerical Investigation of Loss Generation Mechanisms of Flow in Turbomachinery by Using Curved Square Duct

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Journal of Thermal Science 2003年第3期12卷 219-224页

作者： Hoshio Tsujita Shimpei Mizuki Gaku Minorikawa atsumasa yamamoto Department of Mechhanical Engineering Hosei University3-7-2 Kajino-choKoganeiTokyoJapanDepartment of Mechhanical EngineeringHosei University3-7-2 Kajino-choKoganeiTokyoJapanDepartment of Mechhanical EngineeringHosei University3-7-2 Kajino-choKoganeiTokyoJapanNational Aerospace Laboratory 7-44-1 Jindaiji-higashi-machi Chofu Tokyo Japan

The secondary flow within a passage of turbomachinery exhibits a complex flow pattern by the effect of the centrifugal and the Coriolis forces. The passage vortex in this secondary flow generates a major part of the losses. However, the mechanism of the loss generation has not been fully clarified yet. In this point of view, the passage vortex is closely examined by the computational method using the two-dimensional curved square ducts as fundamental models. The inlet boundary layer thickness and the inlet velocity distortion are considered to be the major parameters affecting the generation of passage vortex in the present study. The computed results revealed that the passage vortex gave the predominant effects for the generation of loss not only in the breakdown process but also in the development process.

关键词： curved duct turbomachinery secondary flow passage vortex loss generation

低展弦比涡轮静叶栅叶片正弯曲作用的试验研究

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机械工程学报 2005年第2期41卷 65-70,76页

作者：陈海生谭春青 yamamoto atsumasa 梁锡智北京航空航天大学宇航学院北京100083 中国科学院工程热物理研究所北京100080 日本航空宇宙技术研究所

对弯曲叶片研究中代表性的HIT涡轮静叶型重新开展了叶片弯曲对低展弦比涡轮静叶栅流场影响的试验研究。测量了直叶片叶栅、+10°、+20°和+30°弯曲叶片叶栅的进、出口流场,分析了叶片弯曲对叶栅出口二次流、总压损失和气流角的影响... 详细信息

对弯曲叶片研究中代表性的HIT涡轮静叶型重新开展了叶片弯曲对低展弦比涡轮静叶栅流场影响的试验研究。测量了直叶片叶栅、+10°、+20°和+30°弯曲叶片叶栅的进、出口流场,分析了叶片弯曲对叶栅出口二次流、总压损失和气流角的影响。结果表明:对该叶型叶栅,叶片正弯曲既不能大幅度降低叶栅二次流损失,也不能改善叶栅出口气流角沿叶高的分布:叶栅出口二次流动、尾缘涡及壁角涡随叶片正弯曲角的增大而增强,而通道涡强度和位置变化不大;该研究结果同以往有关文献的研究结果完全不同。

关键词：涡轮静叶栅弯曲叶片试验流场

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平面涡轮叶栅内旋涡结构的试验研究

机械工程学报 2010年第12期46卷 155-160页

作者：张华良谭春青陈海生山本孝正中国科学院工程热物理研究所北京100190 日本宇宙航空研究开发机构

选择3种典型的平面涡轮叶栅,叶型折转角分别为68o、113o和160o,通过对其内部流场进行详细测量和流动分析,讨论叶型折转角对出口涡量分布、气流角分布以及流动损失的影响,并获得3种典型叶栅的旋涡模型。结果表明,在平面涡轮叶栅中存在着... 详细信息

选择3种典型的平面涡轮叶栅,叶型折转角分别为68o、113o和160o,通过对其内部流场进行详细测量和流动分析,讨论叶型折转角对出口涡量分布、气流角分布以及流动损失的影响,并获得3种典型叶栅的旋涡模型。结果表明,在平面涡轮叶栅中存在着复杂的旋涡结构,而且对于不同的叶型折转角,旋涡模型也不同:随着叶型折转角的增加,流场中通道涡的强度不断增强,其位置也不断向叶片中部移动;受其影响,尾缘涡在整个流场中的地位则随着叶型折转角的增加而逐步降低。旋涡结构的变化会引起叶栅出口的气流角、密流和损失分布的明显差别,可以通过控制旋涡结构来重新组织流场。因此,认识叶栅内旋涡结构的基本特征可以为气动优化策略的选择提供依据。

关键词：折转角旋涡结构气流角损失

Higher levels of the lipophilic antioxidants coenzyme Q_(10) and vitamin E in long-lived termite queens than in short-lived workers

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Insect Science 2024年第1期31卷 201-210页

作者： Eisuke Tasaki Yorihiro yamamoto Yoshihito Iuchi Department of Biological Chemistry Graduate School of Sciences and Technology for InnovationYamaguchi UniversityYamaguchiJapan School of Bioscience and Biotechnology Tokyo University of TechnologyHachiojiTokyoJapan

Termite queens and kings live longer than nonreproductive *** molecular mechanisms contributing to their long lifespan have been investigated;however,the underlying biochemical explanation remains *** Q(CoQ),a component of the mitochondrial electron transport chain,plays an essential role in the lipophilic antioxidant defense *** beneficial effects on health and longevity have been well studied in several ***,we demonstrated that long-lived termite queens have significantly higher levels of the lipophilic antioxidant CoQ_(10) than *** chromatography analysis revealed that the levels of the reduced form of CoQ_(10) were 4 fold higher in the queen's body than in the worker's *** addition,queens showed 7 fold higher levels of vitamin E,which plays a role in antilipid peroxidation along with CoQ,than ***,the oral administration of CoQ_(10) to termites increased the CoQ_(10) redox state in the body and their survival rate under oxidative *** findings suggest that CoQ_(10) acts as an efficient lipophilic antioxidant along with vitamin E in long-lived termite *** study provides essential biochemical and evolutionary insights into the relationship between CoQ_(10) concentrations and termite lifespan extension.

关键词： antioxidant defense system coenzyme Q termite queens vitamin E

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低负荷弯叶栅流谱结构与气动性能的实验研究

实验流体力学 2013年第1期27卷 46-51页

作者：张华良谭春青陈海生山本孝正中国科学院工程热物理研究所北京100190 日本宇宙航空研究开发机构

在一套典型的低负荷矩形涡轮静叶栅中开展弯叶片影响叶栅内部流谱结构与气动性能的实验研究。利用微型5孔探针分别对6套叶栅的进出口流场进行详细测量,并在叶栅表面和端壁进行油流显示实验。从定性和定量的角度考察了叶片弯曲对壁面流... 详细信息

在一套典型的低负荷矩形涡轮静叶栅中开展弯叶片影响叶栅内部流谱结构与气动性能的实验研究。利用微型5孔探针分别对6套叶栅的进出口流场进行详细测量,并在叶栅表面和端壁进行油流显示实验。从定性和定量的角度考察了叶片弯曲对壁面流谱拓扑结构、出口涡量、出气角及二次流损失分布的影响,总结了弯叶片影响边界层迁移与二次流损失发展的规律。

关键词：弯叶片低负荷旋涡结构拓扑二次流损失

在高负荷涡轮叶栅中应用弯叶片控制流动分离的实验研究

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工程热物理学报 2009年第9期30卷 1467-1471页

作者：谭春青张华良董学智赵洪雷山本孝正中科院工程热物理研究所北京100190 日本宇宙航空研究开发机构

本文选择叶型折转角为113°和160°的两种高负荷涡轮平面叶栅,分别开展了直叶栅(STR)和正/反弯曲叶栅的流场测量和流动显示研究,讨论了叶片弯曲对壁面流谱和流动损失的影响。实验结果表明:当叶型折转角为113°时,适当的正弯叶片(DHP)可... 详细信息

本文选择叶型折转角为113°和160°的两种高负荷涡轮平面叶栅,分别开展了直叶栅(STR)和正/反弯曲叶栅的流场测量和流动显示研究,讨论了叶片弯曲对壁面流谱和流动损失的影响。实验结果表明:当叶型折转角为113°时,适当的正弯叶片(DHP)可以减少叶栅流动损失;当叶型折转角为160°时,适当的反弯叶片(DHN)能提高叶栅气动性能。

关键词：高负荷折转角流动分离弯叶片

Mission of the National Cancer Center Hospital in Japan to promote clinical trials for precision medicine

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Cancer Biology & Medicine 2024年第1期21卷 1-3页

作者： Kazuaki Shimada Kenichi Nakamura Noboru yamamoto Department of Hepatobiliary and Pancreatic Surgery National Cancer Center HospitalTokyo 104-0045Japan Clinical Research Support Offce National Cancer Center HospitalTokyo 104-0045Japan Department of Experimental Therapeutics National Cancer Center HospitalTokyo 104-0045Japan

Precision medicine is a growing field *** its potential benefit to many patients,several major obstacles must be overcome before precision medicine can be more widely used in clinical *** main obstacles are associated... 详细信息

关键词： clinical Cancer overcome

A new electric field mill array with each of the mill’s rotor controlled precisely by a GPS module:Equipment and initial results

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Earth and Planetary Physics 2024年第2期8卷 423-435页

作者： Kozo Yamashita Hironobu Fujisaka DaoHong Wang Hiroyuki Iwasaki Kazuo yamamoto Koichiro Michimoto Masashi Hayakawa Department of Production Systems Engineering and Sciences Komatsu UniversityNu 1-3 Shicho-machiKomatsuIshikawa 923-8511Japan Fujisaka Technology Office 1058-5 Yoshizawa-choOhta-shiGunma 373-0019Japan Department of Electrical Electronic and Computer EngineeringGifu University1-1 YanagidoGifu CityGifu 501-1193Japan Cooperative Faculty of Education Gunma University4-2-Aramaki-machiMaebashiGunma 371-8510Japan Department of Electrical and Electronic Engineering Chubu University1200 Matsumoto-choKasugaiAichi 487-8501Japan Independent Researcher Kosenba Town 2-44-11-406Kawagoe CitySaitama350-0036Japan Advanced Wireless&Communications Research Center The University of Electro-Communications1-5-1 ChofugaokaChofuTokyo 182-8585Japan

We have newly designed an electrostatic sensor,called an electric field mill(EFM),to simplify the estimation of the charge position and charge amount transferred by lightning *** is necessary for this remote estimation of the transferred charge to measure electric field changes caused by charge loss at the time of a lightning strike at multiple *** multiple-station measurement of electric field changes,not only speed but also phase for exposure and shielding of the sensing plates inside each EFM of the array should be synchronized to maintain the sensitivities of the deployed ***,there is no such EFM with specified speed and phase control performance of the rotary ***,we developed a new EFM in which the rotary mechanism was controlled consistently to within 3%error by a GPS *** EFMs had been distributed in the Hokuriku area of Japan during the winter season of 2022-2023 for a test *** we describe the design and a simple calibration method for our new EFM *** analysis method based on the assumption of a simple monopole charge structure is also *** validation,locations of assumed point charges were compared with three-dimensional lightning mapping data estimated by radio observations in the MF-HF *** results indicated the validity to estimate transferred charge amounts and positions of winter cloud-to-ground lightning discharges with our new EFM array.

关键词： lightning electrostatic field electric field mill electric field change