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A general alternate loading technique and its applications in the inverse designs of centrifugal and mixed-flow pump impellers

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Science China(Technological Sciences) 2021年第4期64卷 898-918页

作者： WANG ChaoYue WANG FuJun AN DongSen YAO ZhiFeng XIAO RuoFu LU Li he chenglian ZOU ZhiChao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China China Institute of Water Resources and Hydropower Research Beijing 100038China China Water Resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

For the inverse designs of centrifugal and mixed-flow pump impellers,clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller *** this paper,to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller,a simple kinematic equation is derived based on the ideal assumptions,which indicates that the potential rothalpy gradient(PRG)is the most important dynamic source that actively induces secondary vortical *** by the natural adverse PRG on the S1 and S2 stream surfaces,two typical secondary flows,H-S and P-S secondary flows,are clearly *** specially suppress these typical secondary flows,a general alternate loading technique(GALT)is proposed,aiming to adjust the real blade loadingδp to control the PRG *** the blade fore part,theδp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 *** the blade middle part,theδp should be moderately decreased to reduce adverse streamwise PRG on the S1 *** the blade aft part,the difference in theδp between the shroud and hub streamlines should be decreased faster to control the exit *** applying the GALT to the impeller designs of three typical pump types in hydraulic engineering,the organizational effect of the PRG on fundamental flow structures is *** GALT can effectively control the PRG distributions and suppress the secondary flows,thereby widening the pump’s high-efficiency zone,improving flow uniformity and suppressing pressure *** with the current Z-G method and the ALT,the GALT can meet the requirements of"de-experience"better,thereby enabling the designers to obtain good products explicitly and quickly.

关键词： alternate loading technique inverse design centrifugal pump mixed-flow pump impeller potential rothalpy gradient

Weather-Driven Solar Power Forecasting Using D-Informer:Enhancing Predictions with Climate Variables

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Energy Engineering 2024年第5期121卷 1245-1261页

作者： chenglian Ma Rui Han Zhao An Tianyu Hu Meizhu Jin School of Electrical Engineering Northeast Electric Power UniversityJilin132013China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen518055China

Precise forecasting of solar power is crucial for the development of sustainable energy *** forecasting approaches often fail to adequately consider the crucial role of weather factors in photovoltaic(PV)power generation and encounter issues such as gradient explosion or disappearance when dealing with extensive time-series *** overcome these challenges,this research presents a cutting-edge,multi-stage forecasting method called *** method skillfully merges the differential transformation algorithm with the Informer model,leveraging a detailed array of meteorological variables and historical PV power generation *** D-Informer model exhibits remarkable superiority over competing models across multiple performance metrics,achieving on average a 67.64%reduction in mean squared error(MSE),a 49.58%decrease in mean absolute error(MAE),and a 43.43%reduction in root mean square error(RMSE).Moreover,it attained an R2 value as high as 0.9917 during the winter season,highlighting its precision and *** significant advancement can be primarily attributed to the incorporation of a multi-head self-attention mechanism,which greatly enhances the model’s ability to identify complex interactions among diverse input variables,and the inclusion of weather variables,enriching the model’s input data and strengthening its predictive accuracy in time series ***,the experimental results confirm the effectiveness of the proposed approach.

关键词： Power forecasting deep learning weather-driven solar power

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尾水管压力脉动的模拟与现场实测

清华大学学报（自然科学版） 2005年第8期45卷 1138-1141页

作者：王正伟周凌九何成连清华大学热能工程系北京100084 中国农业大学水利与土木工程学院北京100083 中水北方勘测设计研究有限责任公司天津300222

通过求解包括导叶、转轮、尾水管3大过流部件在内的水轮机流道内的三维不稳定Reynolds平均Navier-Stokes方程,获得了不同开度部分负荷下的尾水管压力脉动特征和涡带特征.计算采用了RNG k-ε模型.对所计算的水轮机,在尾水管进人门中心对... 详细信息

通过求解包括导叶、转轮、尾水管3大过流部件在内的水轮机流道内的三维不稳定Reynolds平均Navier-Stokes方程,获得了不同开度部分负荷下的尾水管压力脉动特征和涡带特征.计算采用了RNG k-ε模型.对所计算的水轮机,在尾水管进人门中心对压力脉动进行了现场实测.计算与实测的比较表明,在开度为65%～80%的范围内,计算所得涡带压力脉动低频频率与实测值吻合良好; 在80%左右开度下,幅值预测也很准确,但65%左右开度下,幅值偏差略大; 结合尾水管内涡带运动特征,对计算方法进行了评价: 由于所采用的k-ε系列模型为统计模型,计算的压力脉动未能反映实测中出现的高频成分.

关键词：水轮机尾水管涡带压力脉动现场实测

Water temperature governs organophosphate ester dynamics in the aquatic food chain of Poyang Lake

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Environmental Science and Ecotechnology 2024年第5期21卷 197-207页

作者： Zhenfei Yan chenglian Feng Yiping Xu Jindong Wang Nannan Huang Xiaowei Jin Fengchang Wu Yingchen Bai State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China College of Environment Hohai UniversityNanjing210098China Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China China National Environmental Monitoring Centre Beijing100012China

Organophosphate esters(OPEs)are increasingly recognized as pervasive environmental contaminants,primarily from their extensive application in flame retardants and *** their widespread presence,the intricacies of OPE bioaccumulation within aquatic ecosystems remain poorly understood,particularly the environmental determinants influencing their distribution and the bioaccumulation dynamics across aquatic food *** we show that water temperature plays a crucial role in modulating the dispersion of OPE in the aquatic environment of Poyang *** quantified OPE concentrations across various matrices,uncovering levels ranging from 0.198 to 912.622 ng L^(-1) in water,0.013e493.36 ng per g dry weight(dw)in sediment,0.026e41.92 ng per g wet weight(ww)in plankton,0.13e2100.72 ng per g dw in benthic invertebrates,and 0.31e3956.49 ng per g dw in wild fish,highlighting a pronounced bioaccumulation ***,the intestines emerged as the principal site for OPE absorption,displaying the highest concentrations among the seven tissues *** the various OPEs,tris(chloroethyl)phosphate was distinguished by its significant bioaccumulation potential within the aquatic food web,suggesting a need for heightened *** propensity for OPE accumulation was markedly higher in benthic invertebrates than wild fish,indicating a differential vulnerability within aquatic *** study lays a foundational basis for the risk assessment of OPEs as emerging contaminants and underscores the imperative to prioritize the examination of bioaccumulation effects,particularly in benthic invertebrates,to inform future environmental safeguarding strategies.

关键词： Organophosphate esters Driving factor Bioaccumulation and biomagnification Ecological risk

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开机过程中的水电站厂房振动分析

水力发电学报 2006年第2期25卷 1-5,15页

作者：练继建秦亮田会静郑伟何成连天津大学建筑工程学院天津300072 天津水利勘测设计研究院天津300222

本文根据水电站厂房及机组结构开机过程原型观测资料,对水工结构振动情况进行分析,并详细探讨了机组起动过程中的轴向力、扭矩、不平衡力等几种主要荷载的变化情况,给出它们的幅值的近似估算。在此基础上,提出一种计算开机过程中厂房结... 详细信息

本文根据水电站厂房及机组结构开机过程原型观测资料,对水工结构振动情况进行分析,并详细探讨了机组起动过程中的轴向力、扭矩、不平衡力等几种主要荷载的变化情况,给出它们的幅值的近似估算。在此基础上,提出一种计算开机过程中厂房结构动力响应的方法。并将通过该方法结合有限元模型计算出的数值结果与实测数据进行比较,证明该方法是可行的。

关键词：水工结构振动分析有限元法水电站厂房开机过程

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欧阳海水电站1号机组水力共振分析

水力发电学报 2005年第3期24卷 115-118,51页

作者：王正伟唐拥军何成连肖建新清华大学热能系北京100084 天津水利水电勘测设计研究院天津300222 湖南欧阳海灌区管理局湖南421836

欧阳海水电站计划进行增容改造,为了保证引水管路和机组的安全稳定运行,需了解水电站的水力特性。从而进行了甩负荷、变负荷和变速试验。做变负荷试验时发现1号机组在小负荷运行区域出现共振现象,在上机架垂直振动,涡壳进口压力、尾水... 详细信息

欧阳海水电站计划进行增容改造,为了保证引水管路和机组的安全稳定运行,需了解水电站的水力特性。从而进行了甩负荷、变负荷和变速试验。做变负荷试验时发现1号机组在小负荷运行区域出现共振现象,在上机架垂直振动,涡壳进口压力、尾水管锥管压力和顶盖压力实测分析发现均含有1 4倍频的相同频率成份。为探知出现此频率的原因,本文对此频率成分做了详细分析,得知它是由于1号机在小负荷工况运行时上冠处叶道涡产生的水力共振频率。

关键词：水力共振叶道涡涡壳进口压力尾水管压力预盖压力

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雷州半岛人龙舞的文化特质及其开发保护

体育科技 2008年第4期29卷 12-15页

作者：何成莲广东海洋大学体育与休闲学院湛江524088

人龙舞是流传于我国雷州半岛的民间传统体育文化艺术,素有"东方一绝"之美誉,2006年入选首批国家非物质文化遗产代表作名录,2007年载入"上海大世界基尼斯之最"。本文从龙文化、红土文化、海洋文化和体育文化等角度分析人龙舞的文化特质... 详细信息

人龙舞是流传于我国雷州半岛的民间传统体育文化艺术,素有"东方一绝"之美誉,2006年入选首批国家非物质文化遗产代表作名录,2007年载入"上海大世界基尼斯之最"。本文从龙文化、红土文化、海洋文化和体育文化等角度分析人龙舞的文化特质和其开发利用价值。

关键词：人龙舞龙文化红土文化海洋文化体育休闲

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流道喷涂对双吸离心泵压力脉动特性影响研究

水利学报 2015年第9期46卷 1097-1102页

作者：姚志峰王福军肖若富杨敏何成连中国农业大学水利与土木工程学院北京100083 北京航天石化技术装备有限公司北京100076 中水北方勘测设计研究有限责任公司天津300222

流道喷涂技术能有效提高水泵过流部件抗磨损能力并降低水力损失,但其对压力脉动特性的影响并不明确。本文采用试验的方法,对一双吸离心泵流道喷涂前后的压力脉动进行同台测试,并分析了混频幅值和频谱特性。结果表明:流道喷涂处理降低了... 详细信息

流道喷涂技术能有效提高水泵过流部件抗磨损能力并降低水力损失,但其对压力脉动特性的影响并不明确。本文采用试验的方法,对一双吸离心泵流道喷涂前后的压力脉动进行同台测试,并分析了混频幅值和频谱特性。结果表明:流道喷涂处理降低了流道粗糙度,减小了水力损失,提高了效率,但同时也改变了水泵固有的压力脉动特性。对于吸水室,喷涂处理缩小了压力脉动稳定区的范围,使小流量工况区的压力脉动峰峰值达到喷涂处理前的2.8倍,加剧了水泵在小流量工况下运行的不稳定性。对于压水室,喷涂处理使靠近隔舌区域在小流量区的压力脉动明显增加,使远离隔舌区域在大流量区的压力脉动增加。而在设计流量区域,喷涂对各个位置压力脉动影响不明显。为了使喷涂技术发挥综合效果,保证水泵运行稳定,应该尽量避免喷涂后的水泵在偏离设计流量工况运行,特别是严格避免水泵在低于0.75倍设计流量工况运行。

关键词：双吸离心泵流道喷涂压力脉动峰峰值

从和谐理论谈高校体育教学中新型师生关系的构建

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体育科技 2006年第3期27卷 10-12页

作者：何成莲广东海洋大学体育系湛江524088

从和谐的基本理论入手,阐述高校体育教育构建和谐发展的新型师生关系的理念、目标和原则及其新型师生关系的构建。

关键词：和谐理论高校体育教学师生关系构建体育教育基本理论和谐发展目标理念