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Experimental and Numerical Investigations on Ignition and LBO Performances for Staged Combustor under Sub-Atmospheric Conditions

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Journal of Thermal Science 2023年第3期32卷 1251-1262页

作者： ZHAO Qianpeng XU Gang mu yong YANG Jinhu WANG Kaixing Laboratory of Light-Duty Gas-Turbine Institute of Engineering ThermophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Innovation Academy for Light-duty Gas Turbine

In order to effectively widen the high-altitude operating limits of the multi-swirl staged combustor,the ignition and lean blow-out(LBO)performances of the model combustor were experimentally acquired under the conditions of room temperature and sub-atmospheric pressure with the altitude ranging from 0 km to 12 km.Moreover,the isothermal flow fields inside a staged model combustor with different sub-atmospheric conditions were simulated.Experimental results show that the minimum ignition and LBO fuel-air ratio(FAR)increase rapidly with the increase of simulated altitude.In addition,as the relative pressure drop of injector increases from1%to 3%,the ignition and LBO performances are gradually improved.Side visualization of the flame by high-speed camera shows that the time-averaged flames under stable combustion have a similar distribution pattern under different pressure drops.The luminous intensity is stratified into dim-bright-dim layers along axial direction.The flame near LBO shrinks to the outlet of pilot stage with a great reduction in luminous intensity.The numerical results reveal that with the decrease of air pressure,the air mass flow rate involved in atomization and combustion is significantly reduced,and the aerodynamic shear force of swirling air is weakened,which are adverse to atomization and fuel-air mixing for airblast atomizer and further lead to the deterioration of ignition and LBO performances.

关键词： ignition lean blow-out sub-atmospheric pressure staged combustor airblast atomizer

New judging model of fuzzy cluster optimal dividing based on rough sets theory

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Journal of Systems Engineering and Electronics 2007年第2期18卷 392-397页

作者： Wang Yun Liu Qinghong mu yong Shi Kaiquan School of Mathematics and System Sciences Shandong Univ. Jinan 250100 P. R. China School of Science Univ. of Jinan Jinan 250022 P. R. China

To investigate the judging problem of optimal dividing matrix among several fuzzy dividing matrices in fuzzy dividing space, correspondingly, which is determined by the various choices of cluster samples in the totality sample space, two algorithms are proposed on the basis of the data analysis method in rough sets theory： information system discrete algorithm （algorithm 1） and samples representatives judging algorithm （algorithm 2）. On the principle of the farthest distance, algorithm 1 transforms continuous data into discrete form which could be transacted by rough sets theory. Taking the approximate precision as a criterion, algorithm 2 chooses the sample space with a good representative. Hence, the clustering sample set in inducing and computing optimal dividing matrix can be achieved. Several theorems are proposed to provide strict theoretic foundations for the execution of the algorithm model. An applied example based on the new algorithm model is given, whose result verifies the feasibility of this new algorithm model.

关键词： Rough sets theory Fuzzy optimal dividing matrix Representatives of samples Fuzzy cluster analysis Information system approximate precision.

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新质生产力发展评价指标体系构建

经济体制改革 2024年第3期 5-15页

作者：蒋永穆乔张媛四川大学经济学院四川成都610065 四川大学马克思主义学院四川成都610065

新质生产力作为高质量发展的重要着力点,需建立相应指标体系指导其加快发展、统筹推进。根据习近平总书记对新质生产力的概念阐释,结合新质生产力发展实际情况,从理论基础、根本目标、基本原则和本质要求四个方面深入剖析新质生产力发... 详细信息

新质生产力作为高质量发展的重要着力点,需建立相应指标体系指导其加快发展、统筹推进。根据习近平总书记对新质生产力的概念阐释,结合新质生产力发展实际情况,从理论基础、根本目标、基本原则和本质要求四个方面深入剖析新质生产力发展评价指标体系的理论逻辑,并以此为基础初步构建反映新发展理念多维要求、体现新质生产力关键特征、符合新质生产力先进本质的新质生产力发展评价指标体系,为新质生产力研究转向定性与定量相结合进行有益尝试,力求为培育和形成新质生产力提供测度标准和行动参考。

关键词：新质生产力评价指标体系理论逻辑行动参考

Numerical Study of Effect of Compressor Swirling Flow on Combustor Design in a MTE

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Journal of Thermal Science 2017年第4期26卷 349-354页

作者： mu yong WANG Chengdong LIU Cunxi LIU Fuqiang HU Chunyan XU Gang ZHU Junqiang Key Laboratory of Light-duty Gas-turbine Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing 100190 China Institute of Qingdao Light-duty Gas-turbine Qingdao 266000China

An effect of the swirling flow on the combustion performance is studied by the computational fluid dynamics(CFD) in a micro-gas turbine with a centrifugal compressor, dump diffuser and forward-flow combustor. The distributions of air mass and the Temperature Pattern Factor(as: Overall Temperature Distribution Factor-OTDF) in outlet are investigated with two different swirling angles of compressed air as 0° and 15° in three combustors. The results show that the influences of swirling flow on the air distribution and OTDF cannot be neglected. Compared with no-swirling flow, the air through outer liner is more, and the air through the inner liner is less, and the pressure loss is bigger under the swirling condition in the same combustor. The Temperature Pattern Factor changes under the different swirling conditions.

关键词：燃烧器数值研究旋转流压缩机设计计算流体力学压缩空气温度分布

Experimental Investigation on Ignition and Lean Blow-out Performance of a multi-sector Centrally Staged Combustor

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Journal of Thermal Science 2014年第5期23卷 480-485页

作者： LIU Fuqiang ZHANG Kaiyu mu yong LIU Cunxi YANG Jinhu Xu Gang ZHU Junqiang Institute of Engineering Thermophysics Chinese Academy of Science

Improvement on extinction and pollution emission have become one of the most prominent research topics in gas turbine.It is widely recognized that the fuel/air mixture distribution in the recirculation zone is a critical factor in improving lean blow-out(LBO) and ignition.This paper proposed a new low emission scheme with fuel staged centrally and hybrid injector to improve flameout and emission.A relative small amount of fuel enters into central pilot airblast atomizer burner and then atomized by inner swirl air.The remaining majority of fuel is directly injected into vane channels of the primary swirler through a series of holes located on the sidewall of the main stage.Only pilot stage is fueled under ignition and lean flameout condition.The uniformity of fuel/air mixture distribution in the primary zone of the new design decreases NOX emission,meanwhile the fuel air mixture in pilot recirculation zone is locally rich to improve flameout and ignition.Experimental investigation was conducted to compare the new scheme with baseline design of dual-swirler in terms of LBO and ignition characteristics under the same condition in a multi-sector combustor.It is found that the fuel-air ratio of ignition limit and LBO decrease with the reference velocity increasing.The experimental results also show that the new scheme successfully improve lean blow-out and broaden the operation range of the combustor.The experimental results indicated that the centrally staged scheme can widen the operation boundary of the combustor and can provide guidance for design and optimization of combustion chamber.

关键词：点火特性燃烧室实验空气混合物性能井喷低NOX排放污染排放

不接地系统跨线两点相继接地故障多级保护技术

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供用电 2024年第5期41卷 56-63页

作者：刘勇刘大鹏穆勇李振成王顺卢泽钰国网冀北电力有限公司唐山供电公司河北唐山063000

针对配电网单点接地故障保护问题已经进行了大量研究,但对于跨线两点相继接地故障保护问题研究甚少。首先,基于不接地系统的后发接地故障暂态等值电路,推导了第二次接地故障时,各线路零序电流和母线零序电压暂态量的表达式,分析了欠阻... 详细信息

针对配电网单点接地故障保护问题已经进行了大量研究,但对于跨线两点相继接地故障保护问题研究甚少。首先,基于不接地系统的后发接地故障暂态等值电路,推导了第二次接地故障时,各线路零序电流和母线零序电压暂态量的表达式,分析了欠阻尼和过阻尼情况下,故障线路与健全线路暂态功率分布差异,发现暂态功率方向法对于两点相继接地故障具有良好的适用性。然后,分析了基于暂态功率方向的相继接地故障多级保护技术在单端供电单回线配电网和两端供电配电网中的应用与整定,进一步对保护级差和两条故障线路相互影响进行了分析。最后,通过仿真验证了该方法的真实性和有效性。该方法算法简单,由馈线终端单独完成,不依赖主站及通信,可以较好地解决不接地系统相继接地故障多级保护问题。

关键词：不接地系统跨线故障两点相继接地暂态特征暂态检测多级保护技术

Numerical and experimental investigation on emission performance of a fuel staged combustor

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Science China(Technological Sciences) 2014年第10期57卷 1941-1949页

作者： LIU FuQiang ZHANG KaiYu LIU CunXi mu yong YANG JinHu XU Gang ZHU JunQiang Institute of Engineering Thermophysics Chinese Academy of Sciences

The low NOx emission technology has become an important feature of advanced aviation engine.A wide range of applications attempt to take advantage of the fact that staged combustion under lean-premixed-prevaporized(LPP)conditions can significantly cut down emission and improve combustion efficiency.This paper proposes a scheme with fuel centrally staged and multi-point injection.The mixing of fuel and air is improved,and the flame temperature is relative low in combustion zone,minimizing the formation of nitrogen oxides(NOx),especially thermal NOx.In terms of the field distribution of equivalence ratio and temperature obtained from Computational Fluid Dynamics(CFD),a chemical reactor network(CRN),including several different ideal reactor,namely perfectly stirred reactor(PSR)and plug flow reactor(PFR),is constructed to simulate the combustion process and predict pollution emission.The influences of the pilot equivalence ratio and percentage of pilot/main fuel on NOx and carbon monoxide(CO)emission were investigated by CRN model.The effects of the pilot fuel and primary fuel on pollution emission were investigated experimentally.Finally,the effects of pilot equivalence ratio and pilot fuel proportion on NOx emission were discussed in detail by comparing predict of CRN and experimental results.

关键词：引燃燃料排放性能实验燃烧室计算流体动力学反应器网络低NOx 数值

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《英美法导论》双语教学实践探索

河北法律职业教育

河北法律职业教育 2024年第4期2卷 34-39页

作者：穆永强谢永波兰州理工大学法学院

伴随中外法律文化交流互鉴的不断加强和我国法学教育国际化的发展,法学本科专业课程双语教学对于培养高素质复合型、具备国际视野的高级专门人才、增强我国法学高等教育的国际竞争力意义重大。这就需要深入了解我国法学专业双语教学的... 详细信息

伴随中外法律文化交流互鉴的不断加强和我国法学教育国际化的发展,法学本科专业课程双语教学对于培养高素质复合型、具备国际视野的高级专门人才、增强我国法学高等教育的国际竞争力意义重大。这就需要深入了解我国法学专业双语教学的含义及双语教学模式,充分认识《英美法导论》课程开展双语教学的必要性及其存在的问题。学校要高度重视双语课程建设和师资培养,大力建设示范性双语教学慕课课程,鼓励双语课程教师开展线上线下相结合的混合式教学改革实践。

关键词：英美法导论双语教学教学模式

乡村振兴背景下乡村校本教研转型的逻辑、困境与路径

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教学与管理 2024年第21期 11-15页

作者：穆泳美李玲芳漆涛贵州师范大学教育学院贵阳550025

乡村振兴为乡村教育的变革提供保障,乡村教育的发展为乡村振兴注入活力。可见,乡村振兴背景下,乡村教育至关重要,而乡村校本教研是推进乡村教育变革的枢纽。当前,乡村校本教研在转型过程中面临着乡村文化营养力供给不足、乡村学校过于... 详细信息

乡村振兴为乡村教育的变革提供保障,乡村教育的发展为乡村振兴注入活力。可见,乡村振兴背景下,乡村教育至关重要,而乡村校本教研是推进乡村教育变革的枢纽。当前,乡村校本教研在转型过程中面临着乡村文化营养力供给不足、乡村学校过于追求同质化和乡村教师角色身份迷失等多方面挑战。通过分析其面临的困境,根据乡村校本教研的三重逻辑提出优化路径,要求建设乡村文化自信、寻求学校异质性发展和深化教师身份认同来积极应对乡村校本教研转型的挑战,以期促进乡村教育的变革发展,助力教育强国的实现。

关键词：乡村校本教研乡村教育乡村振兴学校异质化发展乡村文化自信