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An exploration for the macroscopic physical meaning of entropy

Science china(Technological Sciences) 2010年第7期53卷 1809-1816页

作者： wu jing1 & guo zengyuan2.1 college of energy and power engineering, nanjing {2. of aeronautics and Astronautics, nanjing 2.0016, china 2.Key Laboratory for Thermal Science and power engineering of Ministry of Education, School of Aerospace, Tsinghua {2., Beijing 100084, china 1. college of energy and {2. engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace Tsinghua University Beijing 100084 China

The macroscopic physical meaning of entropy is analyzed based on the exergy (availability) of a combined system (a closed system and its environment), which is the maximum amount of useful work obtainable from the system and the environment as the system is brought into equilibrium with the environment. The process the system experiences can be divided in two sequent sub-processes, the process at constant volume, which represents the heat interaction of the system with the environment, and the adiabatic process, which represents the work interaction of the system with the environment. It is shown that the macroscopic physical meaning of entropy is a measure of the unavailable energy of a closed system for doing useful work through heat interaction. This statement is more precise than those reported in prior literature. The unavailability function of a closed system can be defined as T0S and p0V in volume constant process and adiabatic process, respectively. Their changes, that is, AiTgS) and A (p0V) represent the unusable parts of the internal energy of a closed system for doing useful work in corresponding processes. Finally, the relation between Clausius entropy and Boltzmann entropy is discussed based on the comparison of their expressions for absolute entropy.

关键词： entropy macroscopic physical meaning exergy heat interaction

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Conversion potential energy and its application to thermodynamic optimization

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Science china(Technological Sciences) 2012年第8期55卷 2169-2175页

作者： wu jing {2. zengyuan college of energy&{2. engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory for Thermal Science and power engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

In general,heat transfers can be classified into two categories according to the purposes of object heating or cooling and the heat to work ***,a new physical quantity,entransy(or potential energy),was proposed to describe the ability of heat transfer with the former *** paper addresses the concept of potential energy in terms of the heat transfer processes for the latter purpose,named the conversion potential *** physical meaning of this newly introduced concept is the potential energy for the heat to work conversion stored in the equivalent mass of heat(thermomass) derived on the basis of the Einstein's special theory of *** dissipation of conversion potential energy occurs during the real irreversible heat to work conversion processes as a measure of the conversion ***,a heat to work conversion problem of a heat exchanger group is provided to show that the minimum conversion potential energy dissipation rate can be used as an optimization criterion for the heat transfer performance with the purpose of the heat to work conversion.

关键词： conversion potential energy entransy optimization exergy thermomass

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A comparison of optimization theories for energy conservation in heat exchanger groups

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Science Bulletin 2011年第Z1期 449-454页

作者： CHEN Qun1,2,wu jing3,WANG MoRan4,PAN Ning2 & guo {2.1 1 Key Laboratory for Thermal Science and power engineering of Ministry of Education,Department of engineering Mechanics,Tsinghua university,Beijing 100084,china 2 Department of Biological and Agricultural engineering,university of California,Davis CA 95616,USA 3 college of energy and power engineering,nanjing university of aeronautics and Astronautics,nanjing 2.0016,china 4 Earth and Environmental Sciences Division,Los Alamos National Laboratory,Los Alamos NM 87545,USA

In general,thermal processes can be classified into two categories: heat-work conversion processes and heat transfer processes. Correspondingly,the optimization of thermal processes has to have two different criteria:the well known entropy generation minimization method and the recently proposed entransy dissipation maximization method. This study analyzes the thermal issues in a heat exchanger group,and optimizes the unit arrangements under different constraints based on a suitable optimization crite-rion. The result indicates that the principle of minimum entropy generation rate is valid for optimizing heat exchangers in a ther-modynamic cycle with given boundary temperatures. In contrast,the entransy dissipation maximization is more suitable in heat exchanger optimizations involving only heat transfer processes. Furthermore,the entropy generation rate induced by dumping used streams into ambient surroundings has to be taken into account,except for that originating from the hot and cold-ends of heat exchangers,when using the entropy generation minimization to optimize heat exchangers undergoing a thermodynamic cycle.

关键词： heat exchangers optimization criterion entransy dissipation maximization entropy generation minimization

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A comparison of optimization theories for energy conservation in heat exchanger groups

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Chinese Science Bulletin 2011年第4期56卷 449-454页

作者： CHEN Qun wu jing WANG MoRan PAN Ning {2. zengyuan Key Laboratory for Thermal Science and power engineering of Ministry of Education Department of Engineering Mechanics Tsinghua University Beijing 100084 China Department of Biological and Agricultural engineering University of California Davis CA 95616 USA college of energy and {2. engineering Nanjing University of Aeronautics andAstronautics Nanjing 210016 China Earth and Environmental Sciences Division Los Alamos National Laboratory Los A lamos NM 87545 USA

关键词：冷端换热器优化理论熵产生率节能传热过程热工过程转换过程过程优化

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Effects of filler loading and surface modification on electrical and thermal properties of epoxy/montmorillonite composite

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Chinese Physics B 2018年第11期27卷 332-339页

作者： Zi-Rui Jia Zhen-guo Gao Di Lan Yong-Hong Cheng Guang-Lei wu Hong-{2. wu School of Science Northwestern Polytechnical UniversityXi'an 710072China Center of Nanomaterials for Renewable energy(CNRE) State Key Laboratory of Electrical Insulation and Power EquipmentSchool of Electrical EngineeringXi'an 3iaotong UniversityXi'an 710049China Institute of Materials for energy and Environment State Key Laboratory Breeding Based of New Fiber Materials and Modem Textile College of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Epoxy-based composites containing montmorillonite(MMT)modified by silylation reaction withγ-aminopropyltriethoxysilane(γ-APTES)and 3-(glycidyloxypropyl)trimethoxysilane(GPTMS)are successfully *** effects of filler loading and surface modification on the electrical and thermal properties of the epoxy/MMT composites are *** with the pure epoxy resin,the epoxy/MMT composite,whether MMT is surface-treated or not,shows low dielectric permittivity,low dielectric loss,and enhanced dielectric *** MMT in the epoxy/MMT composite also influences the thermal properties of the composite by improving the thermal conductivity and *** functionalization of MMT not only conduces to the better dispersion of the nanoparticles,but also significantly affects the electric and thermal properties of the hybrid by influencing the interfaces between MMT and epoxy *** interfaces are good for enhancing the electric and thermal properties of *** is more,the MMT modified with GPTMS rather thanγ-APTES is found to have greater influence on improving the interface between the MMT filler and polymer matrices,thus resulting in lower dielectric loss,lower electric conductivity,higher breakdown strength,lower thermal conductivity,and higher thermal stability.

关键词： modified epoxy resin surface modification electric property thermal property

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一种多段机翼水面起降地效无人机气动特性

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航空兵器 2024年第3期31卷 119-128页

作者：刘战合夏陆林马云鹏王菁张芦吴浩坤郑州航空工业管理学院航空宇航学院郑州450046 大连海事大学船舶与海洋工程学院辽宁大连116026 北京航空航天大学航空科学与工程学院北京100191 武汉理工大学航海与能源动力学院武汉430070

为改善水面起降性能和气动性能,基于船身式机身、多段机翼和T尾融合设计思路,提出并设计了一种新型仿生式多段机翼地效无人机方案,采用N-S方程和K-Ω-SST湍流模型,详细研究了该型无人机在不同状态下的压力云图、压力系数及升阻特性。仿... 详细信息

为改善水面起降性能和气动性能,基于船身式机身、多段机翼和T尾融合设计思路,提出并设计了一种新型仿生式多段机翼地效无人机方案,采用N-S方程和K-Ω-SST湍流模型,详细研究了该型无人机在不同状态下的压力云图、压力系数及升阻特性。仿真结果表明,地效作用随离水高度的增加而减小,离水高度与平均几何弦长之比(高度弦长比H/c)接近1时,地效作用较为显著,无人机在离水高度0.2.m时,升力系数、升阻比分别提升2..91%和40.37%,阻力系数降低15.2.%;对提出的多段机翼布局,地效飞行主要影响下表面压力系数和压力云图,下表面压力系数展向上由内向外正压增幅逐渐减小,弦向上前后缘附近压力系数较小,结合压力云图分析,地效对升力增幅的影响主要集中在中段和内段机翼下方区域;地效飞行可明显提高升力线斜率(H/c为1时提高了8.89%),迎角增加时升力系数增幅和阻力系数降幅均逐渐变大,升阻比增幅(H/c为1)在迎角2.后均达到2.%以上;通过验证机的多轮水面起降和有、无地效飞行试验,证明设计方案具有优秀的气动性能和飞行性能,可为水质检测、水面地效运输、搜救侦察等提供应用平台。

关键词：多段机翼水面起降气动性能无人机地面效应船身式

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Novel lead-free NaNbO_(3) -based relaxor antiferroelectric ceramics with ultrahigh energy storage density and high efficiency

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Journal of Materiomics 2022年第2期8卷 295-301页

作者： Jie Jiang Xiongjie Li Ling Li Shun guo Ji Zhang jing Wang Heguo Zhu Yiping Wang Shan-Tao Zhang School of Materials Science and engineering Nanjing University of Science and TechnologyNanjing210094China State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Jiangsu Key Laboratory of Artificial Functional Materials&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

The development of environmentally friendly ceramics for electrostatic energy storage has drawn growing interest due to the wide application in high power and/or pulsed power electronic ***,it is difficult to simultaneously achieve ultrahigh recoverable energy storage density(W rec>8 J/cm^(3))and high efficiency(η>80%),which restricts their application in the miniaturized,light weight and easy integrated electronic ***,the novel NaNbO_(3)-(Bi_(0.8)Sr_(0.2.)(Fe_(0.9) Nb_(0.1))O_(3) relaxor antiferro-electric ceramics,which integrates the merits of antiferroelectrics and relaxors,are demonstrated to exhibit stabilized antiferroelectric phase and enhanced dielectric relaxor *** particular impor-tance is that the 0.88NN-0.12.SFN ceramic achieves giant electric breakdown strength E_(b)=98.3 kV/mm,ultrahigh W _(rec)=16.5 J/cm^(3) and high h=83.3%,as well as excellent frequency,cycling and thermal reliability *** comprehensive energy storage performance of NN-BSFN not only out-performs state-of-the-art dielectric ceramics by comparison,but also displays outstanding potential for next-generation energy storage capacitors.

关键词： Lead-free NaNbO_(3) Relaxor antiferroelectric energy storage property

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电力线谐波辐射对电离层高能电子的影响

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北京航空航天大学学报 2018年第11期44卷 2329-2335页

作者：张翀吴静马齐爽郭强北京航空航天大学自动化科学与电气工程学院北京100083

电力线谐波辐射(PLHR)作为一种人为的电离层电磁环境污染源被广泛认可,其对电离层状态的影响亟待研究。基于DEMETER卫星高能粒子探测器(IDP)的数据,采用PLHR事件自轨道和发生前后重访轨道综合分析的方法,研究了中国电离层中发现的72.P... 详细信息

电力线谐波辐射(PLHR)作为一种人为的电离层电磁环境污染源被广泛认可,其对电离层状态的影响亟待研究。基于DEMETER卫星高能粒子探测器(IDP)的数据,采用PLHR事件自轨道和发生前后重访轨道综合分析的方法,研究了中国电离层中发现的72.PLHR事件发生前后电离层高能电子投掷角、低中高3个能带的电子通量的影响。结果表明,在PLHR发生前极少数事件出现了投掷角增大的现象,且低能带的电子通量倾向于减小的趋势。这可能是PLHR产生的影响,也可能是由于电离层高能电子状态的这种变化导致PLHR更容易被探测到。

关键词：电力线谐波辐射(PLHR) 卫星探测电离层测量空间研究 DEMETER

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气动载荷下航空发动机的传感器测点选择方法

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机械制造与自动化 2024年第5期53卷 209-212,233页

作者：吴凡琦臧朝平高东武敬彤谭莉张秉杰王鑫南京航空航天大学能源与动力学院江苏南京210016 中国航发沈阳发动机设计研究所辽宁沈阳110066

提出一种气动载荷下航空发动机的传感器测点选择方法。基于航空发动机相似设计的单转子试验器有限元模型,建立气动载荷表征模型。提出响应计算方法,根据整机机匣表面响应来计算关于气动载荷的灵敏度。基于灵敏度分析结果,采用有效独立法... 详细信息

提出一种气动载荷下航空发动机的传感器测点选择方法。基于航空发动机相似设计的单转子试验器有限元模型,建立气动载荷表征模型。提出响应计算方法,根据整机机匣表面响应来计算关于气动载荷的灵敏度。基于灵敏度分析结果,采用有效独立法,分析机匣表面测点的独立性。结合灵敏度与独立性,选择传感器布置最佳测点,并与对照组进行了响应对比。研究结果表明:最佳测点的响应比对照组至少高8倍,验证了该方法的有效性。

关键词：航空发动机气动载荷灵敏度分析传感器布置

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CEPC Technical Design Report

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Radiation Detection Technology and Methods 2024年第1期8卷 I0003-I0016,1-1091页

作者： Waleed Abdallah Tiago Carlos Adorno de Freitas Konstantin Afanaciev Shakeel Ahmad Ijaz Ahmed Xiaocong Ai Abid Aleem Wolfgang Altmannshofer Fabio Alves Weiming An Rui An Daniele Paolo Anderle Stefan Antusch Yasuo Arai Andrej Arbuzov Abdesslam Arhrib Mustafa Ashry Sha Bai Yu Bai Yang Bai Vipul Bairathi Csaba Balazs Philip Bambade Yong Ban Tripamo Bandyopadhyay Shou-Shan Bao Desmond P.Barber Ayse Bat Varvara Batozskaya Subash Chandra Behera Alexander Belyaev Michele Bertucci Xiao-Jun Bi Yuanjie Bi Tianjian Bian Fabrizio Bianchi Thomas Biekotter Michela Biglietti Shalva Bilanishvili Deng Binglin Denis Bodrov Anton Bogomyagkov Serge Bondarenko Stewart Boogert Maarten Boonekamp Marcello Borri Angelo Bosotti Vincent Boudry Mohammed Boukidi Igor Boyko Ivanka Bozovic Giuseppe Bozzi Jean-Claude Brient Anastasiia Budzinskaya Masroor Bukhari Vladimir Bytev Giacomo Cacciapaglia Hua Cai Wenyong Cai wujun Cai Yijian Cai Yizhou Cai Yuchen Cai Haiying Cai Huacheng Cai Lorenzo Calibbi Junsong Cang guofu Cao Jianshe Cao Antoine Chance Xuejun Chang Yue Chang Zhe Chang Xinyuan Chang Wei Chao Auttakit Chatrabhuti Yimin Che Yuzhi Che Bin Chen Danping Chen Fuqing Chen Fusan Chen Gang Chen guoming Chen Hua-Xing Chen Huirun Chen Jinhui Chen Ji-Yuan Chen Kai Chen Mali Chen Mingjun Chen Mingshui Chen Ning Chen Shanhong Chen Shanzhen Chen Shao-Long Chen Shaomin Chen Shiqiang Chen Tianlu Chen Wei Chen Xiang Chen Xiaoyu Chen Xin Chen Xun Chen Xurong Chen Ye Chen Ying Chen Yukai Chen Zelin Chen Zilin Chen Gang Chen Boping Chen Chunhui Chen Hok Chuen Cheng Huajie Cheng Shan Cheng Tongguang Cheng Yunlong Chi Pietro Chimenti Wen Han Chiu Guk Cho Ming-Chung Chu Xiaotong Chu Ziliang Chu Guglielmo Coloretti Andreas Crivellin Hanhua Cui Xiaohao Cui Zhaoyuan Cui Brunella D'Anzi Ling-Yun Dai Xinchen Dai Xuwen Dai Antonio De Maria Nicola De Filippis Christophe De La Taille Francesca De Mori Chiara De Sio Elisa Del Core Shuangxue Deng Wei-Tian Deng Zhi Deng Ziyan Deng Bhupal Dev Tang Dewen Biagio Di Micco Ran Ding Siqin Dingl Yadong Ding Haiyi Dong Jianin AGH university of Science and Technology Faculty of Physics and Applied Computer ScienceKrakow Anhui university HefeiAnhui Applied Physics Department Federal Urdu University of ArtsScience and TechnologyIslamabad Banaras Hindu university Institute of ScienceVaranasi Bandirma Onyedi Eylul university Bandirma Beihang university Beijing Beijing Computational Science Research Center Beijing Beijing Conveyi LTD Beijing Beijing Glass Research Institute Co. LtdBeijing Beijing Institute of Technology Beijing Beijing Normal university Beijing Brown university ProvidenceRI Budker Institute of Nuclear Physics Novosibirsk Cadi Ayyad university Laboratory of Fundamental and Applied PhysicsPolydisciplinary FacultyMarrakech Cairo university Giza Center for Theory and Computation National Tsing Hua UniversityHsinchu Central china Normal university WuhanHubei Central South university ChangshaHunan Centro de Fisica Teorica de Particulas Universidade Tecnica de LisboaLisboa Chengdu KaitengSifang Digital Radio&TV Equipment Co. LtdChengduSichuan china academy of engineering physics MianyangSichuan china building materials academy Beijing china Center of Advanced Science and Technology Beijing china Institute of Atomic energy Beijing china Jiliang university HangzhouZhejiang china Nuclear Instrument CO. LTDBeijing china university of Geosciences Beijing china university of Geosciences WuhanHubei china university of Mining and Technology XuzhouJiangsu china West Normal university NanchongSichuan Chongqing university Department of PhysicsChongqing Chulalongkorn university Bangkok City university of Hong Kong Department of PhysicsHong Kong Cockcroft Institute Daresbury Cornell university IthacaNY CPPM(AMU/IPhU&CNRS/INP) Marseille Dalian Minzu university DalianLiaoning Dalian university of Technology Department of PhysicsDalian Deutsches Elektronen-Synchrotron DESY Hamburg Dzhelepov Laboratory of Nuclear Problems of Joint Institute for Nuclear Research(DLNP JINR) Dubna East china university Of Science And Technol

The Circular Electron Positron Collider(CEPC)is a large scientific project initiated and hosted by china,fostered through extensive collaboration with international *** complex comprises four accelerators:a 30 GeV Linac,a 1.1 GeV Damping Ring,a Booster capable of achieving energies up to 180 GeV,and a Collider operating at varying energy modes(Z,W,H,and tt).The Linac and Damping Ring are situated on the surface,while the subterranean Booster and Collider are housed in a 100 km circumference underground tunnel,strategically accommodating future expansion with provisions for a potential Super Proton Proton Collider(SPPC).The CEPC primarily serves as a Higgs *** its baseline design with synchrotron radiation(SR){2. of 30 MW per beam,it can achieve a luminosity of 5×10^(34)cm^(-2.s^(-1)per interaction point(IP),resulting in an integrated luminosity of 13 ab^(-1)for two IPs over a decade,producing 2.6 million Higgs *** the SR {2. to 50 MW per beam expands the CEPC's capability to generate 4.3 million Higgs bosons,facilitating precise measurements of Higgs coupling at sub-percent levels,exceeding the precision expected from the HL-LHC by an order of *** Technical Design Report(TDR)follows the Preliminary Conceptual Design Report(Pre-CDR,2.15)and the Conceptual Design Report(CDR,2.18),comprehensively detailing the machine's layout,performance metrics,physical design and analysis,technical systems design,R&D and prototyping efforts,and associated civil engineering ***,it includes a cost estimate and a preliminary construction timeline,establishing a framework for forthcoming engineering design phase and site selection *** is anticipated to begin around 2.2.-2.2.,pending government approval,with an estimated duration of 8 *** commencement of experiments and data collection could potentially be initiated in the mid-2.30s.

关键词： initiated exceeding precise

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