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Comprehensive Exergoeconomic Analysis and Optimization of a Novel Zero-Carbon-Emission Multi-Generation System based on Carbon Dioxide Cycle

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Journal of Thermal Science 2024年第3期33卷 1065-1081页

作者： SUN Yan LI Hongwei WANG Di du changhe School of Energy and Power Engineering Northeast Electric Power UniversityJilin132012China School of Automation Engineering Northeast Electric Power UniversityJilin132012China Xi’an Institute of Electromechanical Information Technology Xi’an710065China

This paper aims to conduct a comprehensive exergoeconomic analysis of a novel zero-carbon-emission multi-generation system and propose a fast optimization method combined with machine learning.The detailed exergoeconomic analysis of a novel combined power,freshwater and cooling multi-generation system is performed in this study.The exergoeconomic analysis model is established by exergy flow theory.A comprehensive exergy,exergoeconomic and environmental analysis is carried out.Five critical decision variables are researched to bring out effects on the multi-generation system exergoeconomic performance.A novel fast optimization method combining genetic algorithm and Bagging neural network is proposed.The advanced nature comparison is made between the proposed system and four similar cases.Results display that increasing the turbine inlet temperature can improve exergy efficiency and decrease the total product unit cost.The multi-generation system exergy destruction directly determines exergy efficiency and total exergy destruction cost rate.The total product unit cost in the cost optimal design case is reduced by 7.7%and 25%,respectively,compared with exergy efficiency optimal design case and basic design case.Compared with four similar cases,the proposed multi-generation system has great advantages in thermodynamic performance and exergoeconomic performance.This paper can provide research methods and ideas for performance analysis and fast optimization of multi-generation system.

关键词： waste heat recovery exergoeconomic analysis supercritical carbon dioxide optimization machine learning

Achieving macroscale superlubricity with ultra-short running-in period by using polyethylene glycol-tannic acid complex green lubricant

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Friction 2023年第5期11卷 748-762页

作者： Changhe Du Tongtong YU Zishuai WU Liqiang ZHANG Ruilin SHEN Xiaojuan LI Min FENG Yange FENG Daoai WANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Qingdao Center of Resource Chemistry and New Materials Qingdao 266100China

Superlubricating materials can greatly reduce the energy consumed and economic losses by unnecessary friction.However,a long pre-running-in period is indispensable for achieving superlubricity;this leads to severe wear on the surface of friction pairs and has become one of the important factors in the wear of superlubricating materials.In this study,a polyethylene glycol-tannic acid complex green liquid lubricant(PEG10000-TA)was designed to achieve macroscale superlubricity with an ultrashort running-in period of 9 s under a contact pressure of up to 410 MPa,and the wear rate was only 1.19×10^(–8)mm^(3)·N^(−1)·m^(−1).This is the shortest running-in time required to achieve superlubricity in Si_(3)N_(4)/glass(SiO_(2)).The results show that the strong hydrogen bonds between PEG and TA molecules can significantly reduce the time required for the tribochemical reaction,allowing the lubricating material to reach the state of superlubrication rapidly.Furthermore,the strong hydrogen bond can share a large load while fixing free water molecules in the contact zone to reduce shear interaction.These findings will help advance the use of liquid superlubricity technology in industrial and biomedical.

关键词： superlubricity running-in period tannic acid green lubricant friction

Evaluation and Trend Analysis of Surface Water Quality in Zhengzhou in 1998-2008

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Chinese Journal of Population,Resources and Environment 2012年第4期10卷 44-51页

作者： du Xile Lu changhe Institute of Geographic Sciences and Natural Resources Research CAS University of Chinese Academy of Sciences

Water pollution is one of the major environmental problems,especially in urban areas.due to rapid urban expansion and industrialization,water pollution in Zhengzhou City,the capital of Henan Province in central China has become a serious problem for its development.In this study,the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI),and the change trend was calculated using methods of Mann-Kendall test and Sen's slope estimator,based on the monitoring data from 1998 to 2008.The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases,implying that most rivers were seriously polluted.However,this serious polltuon is expected to be gradually improved,as the concentration of water pollutants and NCPI declined significantly in most rivers.Water pollution in reservoirs was much lower than rivers,and the NCPI in the three monitored reservoirs was lower than 3 in most years,and shows a downward trend.Although the surface water quality was gradually improved,great efforts are still needed to enhance the protection and improvement of surface water environment.

关键词：水环境质量评价地表水环境郑州市 Mann-Kendall检验 NCPI 综合污染指数监测数据水体污染

Trends of Urban Air Pollution in Zhengzhou City in 1996-2008

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Chinese Geographical Science 2012年第4期22卷 402-413页

作者： du Xile LU changhe WANG Hairong MA Jianhua Institute of Geographic Sciences and Natural Resources Research Chinese Academy Sciences Beoing 100101 China' Graduate University of Chinese Academy of Sciences Beijing 100049 China The Second Battalion ofNon-ferrous Metal Geology and Mineral Resources Bureau Zhengzhou 450016 China Institute ofNatural Resources and Environmental Science Henan University Kaifeng 475004 China)

Urban air pollution is a commonly concerned environmental problem in the world.Identification of air quality trend using long-term monitoring data is helpful to understand the effectiveness of pollution control strategies.This study,using data from six monitoring stations in Zhengzhou City,analyzed the changing trend in concentrations of SO 2,NO x /NO 2 and TSP/PM 10 in 1996-2008,based on non-parametric Mann-Kendall test and Sen's slope estimator,and evaluated the comprehensive air pollution level using Multi-Pollutant Index(MPI).It was found that the concentration of each pollutant exceeded obviously the World Health Organization(WHO) guideline value,but the changing trend varied:SO 2 and NO 2 were significantly increased mainly due to an increase in coal consumption and vehicle number,while NO x,TSP and PM 10 decreased.The air pollution was serious,and differed markedly among the three functional regions:it is the most severe in the Industrial and Residential Area(IRA),followed by the Transportation Hub and Business District(THBD),and then the High-tech,Cultural and Educational Area(HCEA).Different from NO 2 concentration that had a similar change trend/rate among the function regions,the change rate of PM 10 concentration differed spatially,decreased much more obviously in THBD than other two regions.For the whole city,the comprehensive air pollution level declined gradually,illustrating that the air quality in Zhengzhou was improved in the last decade.

关键词：城市大气污染郑州市 Mann-Kendall检验发展趋势城市空气污染 PM10浓度污染物浓度空气质量

Charge storage coating based triboelectric nanogenerator and its applications in self-powered anticorrosion and antifouling

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Frontiers of Materials Science 2023年第1期17卷 163-173页

作者： Zhitao Zhang Yupeng Liu Min Feng Nannan Wang Changhe Du Shu Peng Yufei Guo Yongjian Liu Ying Liu Daoai Wang Institute of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Center of Materials Sciences and Opto-Electronic Technology University of Chinese Academy of SciencesBejing 100049China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China QingdaoCenter ofResourceChemistry and NewMaterials Qingdao266100China Institute of Sustainability for Chemicals Energy and Environment(ISCE2)A*STARSingapore 138634Singapore

As a novel energy-harvesting device,a triboelectric nanogenerator(TENG)can harvest almost all mechanical energy and transform it into electrical energy,but its output is low.Although the micro-nano structures of triboelectrode surfaces can improve their output efficiency,they lead to high costs and are not suitable for large-scale applications.To address this problem,we developed a novel TENG coating with charge-storage properties.In this study,we modified an acrylic resin,a friction material,with nano-BaTiO_(3) particles and gas phase fluorination.The charge-trapping ability of nanoparticles was used to improve the output of TENG.The short-circuit current and the output voltage of coating-based TENGs featuring charge storage and electrification reached 15μA and 800 V,respectively,without decay for longtime working.On this basis,self-powered anticorrosion and antifouling systems are designed to reduce the open circuit potential of A3 steel by 510 mV and reduce the adhesion rate of algae on the surface of metal materials.This study presents a high-output,stable,coating-based TENG with potential in practical applications for anticorrosion and antifouling.

关键词： triboelectric nanogenerator charge-trapping anticorrosion antifouling

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球窝/球凸结构下的U型通道蒸汽冷却性能

西安交通大学学报 2015年第9期49卷 63-69页

作者：李森李亮杜长河西安交通大学能源与动力工程学院西安710049

采用标准k-ω湍流模型研究了球窝/球凸结构下U型通道内蒸汽的传热与阻力特性,计算、分析了雷诺数为1×10^4~5×10^4、来流温比为0.79~0.93、出口压力为0.5~3MPa时通道内的流动与传热性能,获得了拟合的传热关联式,对比了蒸汽与空气冷却... 详细信息

采用标准k-ω湍流模型研究了球窝/球凸结构下U型通道内蒸汽的传热与阻力特性,计算、分析了雷诺数为1×10^4~5×10^4、来流温比为0.79~0.93、出口压力为0.5~3MPa时通道内的流动与传热性能,获得了拟合的传热关联式,对比了蒸汽与空气冷却特性的差异。研究结果表明：雷诺数增加在提升总体传热效果的同时能够有效降低流动阻力系数;来流温比增大对强化传热的作用并不明显,但可以有效降低流动阻力损失;提高出口压力可以有效增强传热效果,但大大增加了流动阻力;出口压力为1.5~2MPa、来流温比为0.84~0.88时蒸汽冷却参数能够获得较为理想的综合换热效果;与空气相比,蒸汽的热物性更容易受到温度和压力的影响,导致传热增强系数的变化较大,此时雷诺数的变化对传热增强系数的贡献并不显著;拟合的传热关联式可以准确预测通道内蒸汽冷却换热系数。

关键词：球窝/球凸 U型通道蒸汽冷却换热系数数值模拟

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抽吸孔对旋流和冲击冷却流动传热特性的影响

西安交通大学学报 2017年第1期51卷 19-24页

作者：杜长河范小军李亮丰镇平西安交通大学叶轮机械研究所西安710049

针对旋流和冲击冷却流动的不同传热特性,建立了简单旋流、复合旋流、简单冲击和复合冲击冷却模型,并在相同涡轮叶片前缘几何腔体和气动条件下进行了数值研究,得到了4种模型下的流线结构以及压力和传热系数分布。研究结果表明:旋流和冲... 详细信息

针对旋流和冲击冷却流动的不同传热特性,建立了简单旋流、复合旋流、简单冲击和复合冲击冷却模型,并在相同涡轮叶片前缘几何腔体和气动条件下进行了数值研究,得到了4种模型下的流线结构以及压力和传热系数分布。研究结果表明:旋流和冲击冷却流动存在明显差别;旋流冷却冷气通过喷嘴沿切向高速射入腔体,形成旋转流动,壁面处冷气压力高,靠近腔体中心线处压力低;冲击冷却冷气通过冲击孔高速垂直射入腔体并冲击在靶面上,在靶面撞击点附近形成压力尖峰区域。显然,旋流和冲击冷却的传热特性存在差异。旋流冷却冷气强烈冲刷腔体壁面,减薄热边界层厚度,形成带状高传热区域;冲击冷却冷气强烈撞击靶面,破坏撞击点附近热边界层,形成圆形的高传热区域。旋流冷却传热分布更均匀,抗横流冲击作用更强。对于旋流冷却,抽吸孔强烈扰动冷气的旋转流动,使带状高传热区域扩大,平均传热强度增大4.5%;对于冲击冷却,抽吸孔对冷气流动结构影响较小,传热强度提升不显著。

关键词：旋流冷却冲击冷却抽吸孔流动传热

蒸汽冷却带肋矩形通道流动和换热特性数值研究

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西安交通大学学报 2016年第3期50卷 62-67页

作者：陈宇佳杜长河李亮西安交通大学叶轮机械研究所西安710049

为了阐明蒸汽冷却带肋矩形通道的换热增强机理,基于三维RANS方程和标准k-ω湍流模型,数值模拟了带肋矩形通道的流场和换热特性,研究了雷诺数、入口宽高比和肋间距对流动和换热特性的影响,进一步分析了努塞尔数与雷诺数、入口宽高比、肋... 详细信息

为了阐明蒸汽冷却带肋矩形通道的换热增强机理,基于三维RANS方程和标准k-ω湍流模型,数值模拟了带肋矩形通道的流场和换热特性,研究了雷诺数、入口宽高比和肋间距对流动和换热特性的影响,进一步分析了努塞尔数与雷诺数、入口宽高比、肋间距之间的关系,由此得出带肋矩形通道的传热关联式。结果表明:肋片的存在破坏了较厚的换热边界层,增强了换热性能。雷诺数增大,平均努塞尔数、综合换热因子均增大,阻力系数小幅上升;宽高比增大,平均努塞尔数、综合换热因子均增大,阻力系数大幅上升;肋间距增大,平均努塞尔数增加,阻力系数先增后减,综合换热因子先减后增。所得传热关联式可为先进燃机蒸汽冷却叶片的设计提供参考。

关键词：带肋矩形通道蒸汽冷却流动换热传热关联式数值模拟

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叶片蒸汽冷却耦合换热特性的数值研究

动力工程学报 2015年第2期35卷 113-118 133页

作者：杜长河李亮丰镇平西安交通大学叶轮机械研究所西安710049

为评估透平叶片的蒸汽冷却效果,以Mark II叶片为对象,采用热流固耦合的数值计算方法,通过与实验数据进行比较考察了不同湍流模型对计算结果的影响,对比分析了空气、过热蒸汽和湿蒸汽冷却效果的差异,研究了冷却蒸汽质量流量、进口湍动度... 详细信息

为评估透平叶片的蒸汽冷却效果,以Mark II叶片为对象,采用热流固耦合的数值计算方法,通过与实验数据进行比较考察了不同湍流模型对计算结果的影响,对比分析了空气、过热蒸汽和湿蒸汽冷却效果的差异,研究了冷却蒸汽质量流量、进口湍动度和叶片表面粗糙度对蒸汽冷却效率的影响.结果表明:SST转捩湍流模型对于流动换热计算有较高的精度;与空气冷却相比,过热蒸汽冷却的效率更高,叶片壁面温度更低;与过热蒸汽冷却相比,湿蒸汽的冷却效率更高,叶片壁面温度更低,且随着蒸汽湿度的增加,冷却效率提高,叶片壁面温度降低;增加冷却蒸汽的质量流量可使冷却效率提高,但冷却蒸汽的温升减小;当湍流强度小于3%时,冷却效率随冷却蒸汽进口湍流强度的增大而提高;增加叶片粗糙度使得叶片冷却效率显著提高.

关键词：热流固耦合换热特性蒸汽冷却湿度冷却效率