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天津大学学报 1986年第2期 95-103页

作者：王日宣毕静天津大学水利工程系

本文通过理论分析、实验研究及计算归纳,得到了坝后式、引水式及河床式水电站厂房地震加速度分布系数的分布规律,给出了其地震荷载的计算方法。从而大大简化了水电站厂房地震荷载的计算。所得结果与美国规范规定的数值相符。

关键词：水电站厂房自振特性地震加速度分布系数河床式水电站地震荷载地震力分布规律

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液压泵脉动机理的研究

天津大学学报 1987年第2期 31-38页

作者：王懋瑶朱洪涛 Tianjin Univ China Tianjin Univ China

本文通过对柱塞泵的流量/压力脉动机理的研究,导出了回冲脉动理论计算公式,并指出,回冲脉动是柱塞泵的主要脉动因素。回冲脉动的控制是柱塞泵脉动控制的关键。

关键词：泵的脉动柱塞泵液压泵

盐浸-冻融-紫外线三因素影响下寒区混凝土坝强震损伤研究

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实验力学 2024年第4期39卷 454-462页

作者：张宇张雪王舒王铭明东北石油大学黑龙江省寒区新能源热利用及防灾减灾重点实验室黑龙江大庆163318 大庆开放大学土木工程系黑龙江大庆163311 昆明理工大学电力工程学院云南昆明650500

为研究盐浸、冻融循环和紫外线辐照耦合作用对寒区混凝土坝的强震损伤影响,进行了三因素循环作用下的混凝土性能劣化试验和高坝抗震性能分析。根据盐浸分析结果配制高浓度盐浸液体,并根据实际情况确定冻融循环次数和紫外线辐射量,揭示盐... 详细信息

为研究盐浸、冻融循环和紫外线辐照耦合作用对寒区混凝土坝的强震损伤影响,进行了三因素循环作用下的混凝土性能劣化试验和高坝抗震性能分析。根据盐浸分析结果配制高浓度盐浸液体,并根据实际情况确定冻融循环次数和紫外线辐射量,揭示盐浸-冻融-紫外线三因素与混凝土材料性能劣化之间的关联性规律;以此为基础,数值分析三因素对坝体强震破坏的影响。结果表明:恶劣环境下,混凝土材料在物理结晶膨胀破坏和化学侵蚀的相互作用下,材料性能劣化不断加深;发生强震时,盐浸-冻融-紫外线三因素改变了高坝的失效模式,降低了高坝的整体抗震性能。上述研究结果有助于深入了解恶劣环境对坝体材料力学性能的影响,并可为寒区水工结构抗震设计提供依据。

关键词：混凝土坝寒区盐浸冻融循环紫外线抗震性能

FLUVIAL PROCESSES IN THE LOWER JINGJIANG RIVER:IMPACT OF THE THREE GORGES RESERVOIR IMPOUNDMENT

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International Journal of Sediment Research 2005年第2期20卷 102-108页

作者： Xuejun SHAO1,Hong wang2 and Zhaoyin wang 1 31Prof.2Asso.Prof.,department of hydraulic engineering,Tsinghua University,Beijing 100084,China Send correspondence to Xuejun Shao 3Prof.Dr.International Research and Training Center on Erosion and Sedimentation(IRTCES),Beijing 100044,China department of hydraulic engineering Tsinghua University Beijing 100084 China department of hydraulic engineering Tsinghua University Beijing 100084 China International Research and Training Center on Erosion and Sedimentation (IRTCES) Beijing 100044 China

Sediment supply to the lower Jingjiang River will be subject to substantial reduction after the impoundment of the Three Gorges Reservoir,which could result in an excess of carrying capacity and serious bank erosions in the downstream alluvial channel,threatening the bank protection works and the safety of the Jingjiang Dyke. This paper presents a summary of research works concerning the fluvial processes in the lower Jingjiang River and the possible impact of the Three Gorges Reservoir impoundment on the variation of its channel pattern. Three different predictions have been put forward by researchers:1) the Jingjiang River will evolve towards a more sinuous,meandering channel pattern,with extensive bank erosion taking place along the river; 2) the river channel will be straightened and broadened because no point bar can be formed due to reduced sediment supply while bank erosion develops in the concave bank,and 3) this river reach will maintain its present channel pattern without significant change,although the sinuosity may be slightly reduced,since:a) the Three Gorges Reservoir mainly intercept sediment particles with sizes larger than 0.025mm,and b) the complex interaction between the Yangtze River and the Dongting Lake helps to reduce the negative effect of channel erosion through certain self-adjusting mechanism in fluvial processes. Discrepancy between these predictions shows that further research efforts are needed to understand the impact of Three Gorges Reservoir operation on the downstream fluvial processes. Meanwhile,there is an urgent need to closely monitor future development in the fluvial processes of the Jingjiang River and its influence on the safety of the Jingjiang Dykes.

关键词： Three Gorges Reservoir Downstream impact Fluvial processes Yangtze River

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“以管代孔”——排水孔模拟方法探讨

岩石力学与工程学报 2001年第3期20卷 346-349页

作者：王恩志王洪涛邓旭东清华大学水利水电工程系北京100084

依据渗流基本原理 ,提出了“以管代孔”模拟岩体排水孔的新方法 ,将排水孔作为强渗透性能的导水管单元反映在渗透介质结构中 ,按流量和水头等价原则确定的单孔等效渗透系数体现了排水孔性能与孔距及岩体渗透性之间的关系 ,能模拟不同条... 详细信息

依据渗流基本原理 ,提出了“以管代孔”模拟岩体排水孔的新方法 ,将排水孔作为强渗透性能的导水管单元反映在渗透介质结构中 ,按流量和水头等价原则确定的单孔等效渗透系数体现了排水孔性能与孔距及岩体渗透性之间的关系 ,能模拟不同条件下的排水效果。

关键词：渗流排水孔岩体数值方法

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太原市地下水污染预测的探讨

太原工业大学学报 1993年第3期24卷 36-41页

作者：王进宝李铭鑫太原工业大学水利工程系

本文通过对太原地下水污染预测的简单分析、评价、研究,介绍了一种适用于大面积地下水污染预测的方法——水量水质耦合法。

关键词：地下水污染含水层渗透系数

Performance prediction and flow analysis in the vaned distributor of a pump turbine under low flow rate in pump mode

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中国科学：技术科学英文版 2010年第12期53卷 3302-3309页

作者： YIN JunLian1, LIU JinTao1, wang LeQin1, JIAO Lei1, WU DaZhuan1 & QIN DaQing2 1 Institute of Chemical Machinery, department of Chemical and Biological engineering, Zhejiang University, Hangzhou 310027, China 2 Harbin Institute of Large Electrical Machinery, Harbin 150001, China Institute of Chemical Machinery Department of Chemical and Biological Engineering Zhejiang University Hangzhou China Harbin Institute of Large Electrical Machinery Harbin China

The main goal of this work is to investigate the possible different flow patterns existing in pump turbine under off-design conditions in pump mode. Numerical simulations by solving the Navier-Stokes equation, coupled with the "SST k-ω" turbulence model, were carried out. Flow characteristics were assumed to be stalled in the appropriate region of ?ow rate levels of Q/QD=0.15–0.61. The simulation result was compared with experimental data and they showed good agreement. Consequently, velocity fields in three axial locations in stay vanes and guide vanes were analysed in details. It was shown that "jet-wake" flow pattern exists near the band, which changes little in the whole shape with flow rate increasing; to the middle location of vanes, reverse flow begins to appear on the interface between the runner and guide vanes, which will disappear gradually as the flow rate increases; massive reverse flow is captured near the crown, whose intensity will be weakened as the flow rate increases. Ultimately, it was found that the special head-flow profile can be ascribed to the special hydraulic loss characteristics of the stay vanes and guide vanes.

关键词： pump turbine flow simulation stalled flow guide vane

Research of New Roll Eccentricity Control for Cold Tandem Mill

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Research of New Roll Eccentricity Control for Cold Tandem Mi...

第五届流体传动与控制国际会议

作者： Zhang Wei wang Yiqun Sun Menghui wang Haifang Mechanical engineering department of Yanshan University Qinhuangdao 066004 China

＜正＞The problem of roll eccentricity for cold tandem mill is proposed,and the influence of eccentricity on strip gauge is *** mathematical model that includes the dynamic characteristic of the hydraulic screw down system has been *** control theory is applied to the roll eccentricity control as the roll eccentricity is a periodic disturbance related to the rotational angle of the *** July 2005,a new roll eccentricity control system was successfully used at WanDa Steel’s works in ZhangJiaGang,*** has contributed to improved thickness accuracy.

关键词： cold tandem mill roll eccentricity control automatic gauge control hydraulic screw down system

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三向变形条件下铜片止水破坏准则研究

水力发电学报 2024年第5期43卷 94-102页

作者：王立安傅中志丁强生王永生南京水利科学研究院岩土工程研究所南京210024 水利部土石坝破坏机理与防控技术重点实验室南京210029 中水北方勘测设计研究有限责任公司天津300222

铜片止水是水工混凝土结构分缝之间最重要的止水构件。混凝土结构在自重和水荷载作用下,常产生不均匀变形,使结构分缝之间的铜片止水产生拉伸(压缩)、沉陷和剪切三向变形(相对位移)。铜片止水的安全性取决于三向变形的量值,常通过三个... 详细信息

铜片止水是水工混凝土结构分缝之间最重要的止水构件。混凝土结构在自重和水荷载作用下,常产生不均匀变形,使结构分缝之间的铜片止水产生拉伸(压缩)、沉陷和剪切三向变形(相对位移)。铜片止水的安全性取决于三向变形的量值,常通过三个方向的位移单独判断,未考虑三向位移的耦合作用。本文设计制作了两种尺寸共计40个铜片止水试件,通过三向加载独立控制的试验平台对铜片止水进行了不同拉伸、沉降位移的剪切试验,研究了铜片止水的剪切变形规律和破坏形态,得到了三维位移空间中的破坏包络面,提出了一个三向变位条件下铜片止水的变形破坏准则,可用于铜片止水的安全性判断。

关键词：铜片止水结构分缝破坏准则混凝土结构