有桩群河道水流紊动特性探究

为了分析桩群对河道水流紊动特性的影响,利用声学多普勒流速仪(ADV)测量了矩形断面明渠中在修建桩群前后不同断面不同垂线、不同测点的三向流速,计算出水质点的三维无量纲化的紊动强度,并分析其分布规律和变化特征.试验表明:水流的横向紊动强度和纵向紊动强度具有相似的分布规律;纵向紊动强度远远大于横向和垂向紊动强度;桩群使水流垂向紊动强度变化幅度最大,该试验研究可为桩群对水流结构的影响分析提供参考.     

常曲率U型弯道水流紊动特性试验研究

采用三维声学多普勒流速仪,对水流三维流速进行了采集,对弯道水流的脉动进行了统计分析,研究了典型断面的紊动强度、紊动切应力、紊动能的分布。试验结果能够很好的揭示弯道水流的三维特性及分布规律。研究成果为进一步研究水流的紊动结构及泥沙的运动机理提供了参考资料。     

应变式水流紊动传感器及紊动流速仪在高含沙水流中的应用

应变式水流紊动传感器及紊动流速仪可应用于高含沙水流紊动流事浓 时均流速的测量，适用含沙量范围为0－666kg/m^3，对传感器的标定及使用表明仪器所采集的信号是可信的，数据是准确的。     

矩形水槽中梯形边墩水流紊动特性试验研究

采用声学多普勒流速仪ADV,对矩形水槽中梯形边墩周围水流紊动特性进行系统的试验研究，并对紊动强度3个方向分量进行了较深入的分析。根据试验数据，通过对柱体周围不同垂直面上紊动强度的分析对比，得出行进水流受到边墩的影响程度，在柱体上游，受到柱体挤压，紊动强烈；在柱体下游，水流从柱体分离，形成逆向回流，紊动强度增大，垂向紊动强度很小，可以忽略。实验可为研究水流紊动结构及桥梁梯形边墩的紊动特性提供验证资料。     

有无植物条件下明渠水流紊动特性对比

在可变坡水槽中,模拟了带枝杈植物对明渠水流的干扰作用,借助超声多普勒流速仪(ADV)测量了不同水深下垂线不同测点的瞬时流速,计算了各测点的三维时均流速、脉动强度及雷诺应力等紊动参数,通过与无植物干扰的明渠均匀流紊动特性进行对比,分析植物对水流紊动参数的影响规律。试验结果表明:在有植物明渠水流中,时均流速呈三区分布特征;脉动强度及雷诺应力均在植物顶部附近出现最大值;脉动强度明显增大,在3个方向上趋于接近;可以用植物顶部以上的雷诺应力分布推求摩阻流速。     

高含沙圆管流的紊动强度分布

明渠高含沙水流紊动特性的研究比较多，而关于高含沙管流紊动的文献则很少见到。我们在管路试验系统中，用应变式紊动流速仪，观测了管道内高含沙水流紊动强度的大小，沿垂线分布以及流速，含沙量对紊动强度大小和分布的影响，初步探讨了流核区内存在紊动，管轴处紊动紊动强度不小于其周围附近点紊动强度值的机理。     

矩形水槽水流紊动特性分析

 采用三维超声流速仪系统地测量矩形水槽水流紊动特性，对紊动拟序结构中的准周期、频率、周期函数、概率密度函数等进行了定量的数学描述，并对时均流速、紊动强度、雷诺应力等沿垂线分布问题作了较为深入的分析计算。为研究水流的紊动结构及悬移质泥沙的运动机理提供了验证资料，加深了对水流紊动结构的了解。     

天然河道水流紊动特性分析

本文采用超声多普勒三向流速仪对不同流量级的条件下长江干流黄陵庙水文观测断面不同垂线的脉动流速进行了观测。根据现场观测资料，对水流的紊动周期、频率、概率密度函数等进行了定量的数学描述，并对时均流速、紊动强度、雷诺应力等沿垂线的分布规律进行了分析计算。结果表明，脉动流速的概率分布在充分发展的自由紊流区近似为正态分布，在近壁强剪切紊流区为偏态分布；各垂线紊动强度在相对水深大于0．4的范围内比较均匀，在接近河底处升高，达到最大值后迅速减小，至河底为零。     

浑水脉动流速量测系统的原理及应用

根据水流中滞点压力与流速平方成正比的关系,本文介绍用硅压阻压力传感器检测滞点流速水头,由计算机进行实时数据采集的浑水脉动流速量测系统的原理及量测成果。通过对清水及推移质换沙水流、悬移质挟沙水流的量测证明,所测清水紊动强度的分布与激光流速仪量测结果一致。并能成功地用于挟沙水流流速的测量。     

ADCP在天然河流大尺度紊动结构研究中的应用

介绍了声学多普勒流速剖面仪(ADCP)在天然河流大尺度紊动结构研究中的应用情况与ADCP的工作原理，并基于符合准恒定、准平衡条件的水流状况，根据大量的实测数据，对天然水流紊动特性进行了分析，加深了对天然水流紊动特性的认识．     

Prediction of boundary shear stress distribution in straight open channels using velocity distribution

Conventional methods for measuring local shear stress on the wetted perimeter of open channels are related to the measurement of the very low velocity close to the boundary.Measuring near-zero velocity values with high fluctuations has always been a difficult task for fluid flow near solid boundaries.To solve the observation problems,a new model was developed to estimate the distribution of boundary shear stress from the velocity distribution in open channels with different cross-sectional shapes.To estimate the shear stress at a point on the wetted perimeter by the model,the velocity must be measured at a point with a known normal distance to the boundary.The experimental work of some other researchers on channels with various cross-sectional shapes,including rectangular,trapezoidal,partially full circular,and compound shapes,was used to evaluate the performance of the proposed model.Optimized exponent coefficients for the model were found using the multivariate Newton method with the minimum of the mean absolute percentage error(MAPE) between the model and experimental data as the objective function.Subsequently,the calculated shear stress distributions along the wetted perimeter were compared with the experimental data.The most important advantage of the proposed model is its inherent simplicity.The mean MAPE value for the seven selected cross-sections was 6.9%.The best results were found in the cross-sections with less discontinuity of the wetted perimeter,including the compound,trapezoidal,and partially full circular pipes.In contrast,for the rectangular cross-section with an angle between the bed and walls of 90°,MAPE increased due to the large discontinuities.     

地形高差对风速影响的探讨

微地形对风速的影响是明显而复杂的。本文研究了风向与地形倾向间不同关系中风速沿同程变化的影响量，并探讨了其变化规律，得出较为满意的地形高差对风速影响量，并探讨了其变化规律，得出较为满意的地形高差对风速影响量估算的方法。可供山、丘区工程设计风速计算中，对工程区与引用气象台（站）观测场地有较大的形高差时，实测高水位期最大风速资料改正值估算的参考。     

新型浓缩澄清综合池试验研究

设计开发了一种新型的集浓缩澄清为一体的综合池中试装置.以江苏某湖水作为试验原水,考察了速度梯度G、进水水力负荷、回流泥渣浓度、泥渣回流比及污泥固体负荷等因素对综合池出水浊度和排泥水含固率的影响.研究结果表明,在达到设计进水负荷及回流泥渣浓度的条件下,控制搅拌梯度在100～115 s~(-1),其出水浊度达到1～2 NTU,排泥水含固率为4.2%～3.9%,此时泥渣回流比为2.5∶1～3∶1.当进水负荷增大至原来的1.2倍时,改变速度梯度至105～120 s~(-1),也可达到最佳运行工况,此时浊度在1～2 NTU,但排泥水含固率减至3.1%～3.0%,泥渣回流比为2.5∶1～2.8∶1.这种新型的浓缩澄清中试装置具有良好的应用前景和工程推广价值.     

趋孔水流运动与冲刷漏斗的成因研究

本文首先扼要介绍了国内外研究冲刷漏斗稳定形态与趋孔水流运动特性的现状,接着归纳了冲刷漏斗稳定形态的基本特征,详细陈述了笔者对趋孔水流运动的试验方法、观测手段和试验结果,得出了趋孔水流的流速分布特性,并据此解释了冲刷漏斗的形成与稳定原因。     

引黄工程总干一级泵站 1a 通风洞口明挖控制爆破设计与施工

本文介绍了一个大体积爆破工程——引黄工程一级泵站１ａ通风洞口石方开挖从爆破设计和爆破振动控制标准的确定、爆破参数优化以及控制爆破施工到爆破安全振动速度计算等方面，重点介绍了控制爆破施工，结果表明，在密集居民区附近进行大体积石方开挖的控制爆破是成功的。爆破对附近设施、建筑物没有影响，施工期间所有设施运转正常。     

葛洲坝大江下航道水流条件分析

航道水流条件是保证船舶航行安全的主要问题之一。葛洲坝大江下游引航道由于受枢纽泄洪影响，航道内存在明显的泄水波和高流速区，造成船舶航行困难，影响安全。因此，现行船舶只在流量２００００ｍ＾３／ｓ以下通行。为此，近年来，对原型水流条件作了大量观测，探讨提高通航流量的可能性。经分析认为，在现行条件下，通航流量可提高到２３０００ｍ＾３／ｓ。     

双级贯流式水轮机导叶和转轮的水力设计

针对一种新型双级贯流式水轮机,推导了一级导叶、一级转轮、二级导叶和二级转轮的参数设计公式。利用数值模拟商业软件Fluent分析了水轮机在设计工况下的数值性能。数值计算时控制方程采用雷诺时均N-S离散方程,湍流模型选择标准k-ε模型,得到了水轮机的流线图、导叶和转轮叶片的压力面和吸力面的压力分布图,以及中心对称面x=0.083 5的速度矢量图,数值计算结果证明了水轮机设计的正确性。     

Analytical solution for a strong free-surface water vortex describing flow in a full-scale gravitational vortex hydropower system

Strong free-surface water vortices are found throughout industrial hydraulic systems used for water treatment, flow regulation, and energy generation. Previous models using the volumetric flow rate as a model input have generally been semi-empirical, and have tended to have some limitations in terms of the design of practical hydropower systems. In this study, an analytical model of a strong free-surface water vortex was developed. This model only requires the water head and geometric parameters as its inputs and calculates the maximum volumetric flow rate, aircore diameter, and rotational constant. Detailed experimental depthedischarge data from a full-scale gravitational vortex hydropower system,unavailable in the relevant literature, were obtained, and the simulated results showed excellent agreement with the experimental observations.These data could be used to verify similar models using laboratory-scale physical models in order to investigate the scaling effects. In contrast to previous models, this model does not assume a constant average velocity across the vortex radius and allows precise calculation of the resultant velocity vectors. Therefore, this model presents advantages in turbine design for energy generation systems.     

New insights into larval lake sturgeon daytime drift dynamics

Drifting post yolk-sac (PYS) lake sturgeon Acipenser fulvescens larvae were believed to seek refuge in substrate during daytime although there were no data to support this theory. There is growing scientific literature on important habitat, such as for adults and where eggs are spawned and hatch, however a gap remains in understanding duration of drift for PYS larvae, especially during daytime. This study was undertaken to find drifting PYS lake sturgeon larvae during the day in the Sturgeon River, Michigan, a clear yet tannin-rich river with a well-studied self-sustaining population. River substrates were mapped, and light, velocity, and depth data gathered to describe ‘believed’ refuge for larvae during daylight. From 2013 through 2016 nighttime drift samples (n = 463) for PYS lake sturgeon larvae were complemented with 143 daytime kick net samples and 43 daytime drift sets. No drifting larvae were collected in the daytime kick nets covering a variety of substrate types while over 1,600 PYS larvae were captured in drift nets at night, and 34 were captured in daytime drift sets. These 34 PYS larvae were in the previously unsampled thalweg in ~5% of surface light and at velocities of 0.24 to 0.57 m/s. Data suggest that drifting PYS lake sturgeon larvae do not stop and seek refuge during daylight but rather drift quickly and continuously downstream until suitable habitat is encountered. Measures of light, depth, velocity and thalweg presence combined with LiDar and Sonar mapping will be critical to understanding river suitability and restoration success for this species.     

赤吟水闸枢纽工程泄洪能力的数值模拟研究

建立赤吟水闸枢纽工程平面二维水流数学模型,对水闸泄洪能力进行了模拟。模型研究了设计洪水和校核洪水时邦庄拦河闸与赤吟橡胶坝的泄流能力、流速分布以及新老河道的分流比,计算了维持上游正常蓄水位时下游不同水位的两汊全开泄流量。结果表明:邦庄拦河闸及赤吟橡胶坝的坝上、下游流速分布都较为均匀,未见明显回流等不良流态;邦庄拦河闸及赤吟橡胶坝泄流能力能够满足要求。