台阶式溢洪道中凹角水流的循环及能量交换是泄洪消能的关键因素之一,目前台阶式溢洪道的研究多集中在台阶的坡度、尺寸以及与宽尾墩等联合运用方面,鲜有对台阶凹角几何形状进行研究.通过水工模型试验和数值模拟计算,对传统三角形凹角台阶和新型梯形凹角台阶的流态、掺气浓度、压强、流速等水力特性进行研究,结果表明:梯形凹角台阶与三角形凹角台阶水流水力特性分布规律相同,但由于梯形凹角台阶改变了旋涡脱落的形状,漩涡脱落进入主流中,促进水流湍动,使得初始掺气点位置略微前移,增加主流区断面平均掺气浓度,提高虚拟底板处总压强波动强度,降低台阶沿程流速,有利于提高台阶抗空化空蚀能力和促进台阶消能.

闸墙长廊道侧支孔输水系统属简单类分散输水形式,采用该形式的船闸在输水过程中侧支孔涌入的水流在闸室内不易均匀分布,常出现闸室内水体剧烈紊动的现象,影响船只的停泊条件,因此常需在闸室内增设消能设施.通过数值模拟的手段研究船闸输水过程中的消力槛的消能机理及消能效果,研究结果表明:布设消力槛可以有效地降低射流进入闸室后的流速,改善闸室内水流流态,具有良好的消能效果.

受下游出口横向宽度有限等因素的影响,泄洪洞扩散式挑坎存在水舌入水面积过大、冲刷下游边坡的现象.针对这一现象,基于那棱格勒水利枢纽工程整体水工模型试验,对比研究扩散式挑坎和等宽式挑坎两种挑坎方案内部流态、水面线、流速、时均压力、出口水舌形态和下游冲刷情况等相关水力学特性.研究结果表明:等宽式挑坎内部横向水面变幅较小,发生空化的可能性较低,水舌入水宽度较小,消能效果充分.在改善挑坎流态,减轻下游岸坡冲刷等方面起到重要作用,有效满足了当地实际地形对于入水水舌的要求和工程运行的需要.

莲花寺电站最大坝高仅有29 m、溢流堰前后最小水位差仅有9.54m,属于典型低水头闸坝工程,这类工程往往具有低佛氏数、下游深尾水以及消力池内消能紊动不足等特点.通过物理模型试验针对莲花寺电站原底孔折线型消力池内消能紊动不充分、淹没水跃滞后、出池水流过大等问题,提出拆除消力池内纵向隔墩、形成表底孔联合消力池,得出以下结论:表底孔联合消力池借助消力池横向宽度,利用表孔、底孔入池水流纵向流速梯度、横向能量差,加剧消力池内横向水流扩散,增强水流碰撞耗散,提升消能效果.尤其是单独开启表孔、底孔泄洪时,入池水流显著向两侧扩散、偏移,形成三元水跃,有效增强消力池上游区域紊动耗散,减小出池水流流速,能为类似闸坝工程提供参考作用.

为研究角木塘水电站溢洪道表孔弧形闸门出现的流激振动现象,通过制作几何比尺为1∶30的完全水弹性相似模型进行相关试验,研究弧形闸门在有无止水时的应力响应和加速度响应特性,以得到闸门在不同开度下应力的规律性变化.试验结果表明,静应力在无止水时的压应力大于有止水时的压应力,动应力在有止水时随闸门开度的增大先增加再减小,加速度在无止水时最大值为0.761g,有止水时最大值为0.699g,加装止水后加速度值减小,振动现象得到改善,动力响应满足闸门抗振设计要求.

在低水头、大单宽流量泄洪建筑物下游普遍存在河床冲刷等问题,结合新集水利枢纽工程、利用水工物理模型试验,通过对比分析原消力池(由连接闸室底板的斜坡段和带尾坎的水平护坦组成)和T型墩+尾坎联合消能工两种方案消力池段及海漫段的流速分布、消力池消能率、流场分布及下游河床冲刷情况,得到以下结论:T型墩+尾坎联合消能工通过扩散和挑起水流,增大池内消能比重,削弱波状水跃[1],降低了出池流速,并在海漫段形成二次水跃,大幅提高了整个消能段消能率,下游河床冲刷明显降低.该消能工优化设计方案为工程的消能优化研究提供了强有力的依据.

基于RNG k-ε 紊流模型,针对消力池内纵向隔墩对比研究了常规隔墩式消力池与表底孔联合消力池三维流场的差异.数值模拟计算结果表明:拆除消力池内纵向隔墩有助于表底孔联合消力池利用表孔与底孔入池水流差异,使其在消力池上游区域激起强烈横向扩散和碰撞,形成由底至表不断发展的立轴旋滚,显著增强消力池内相邻水股剪切紊动耗散,尤其当底孔单独运行时消力池内过流宽度突变使入池水流形成显著三维水跃,沿程平均流速下降35％～49％,从而改善消力池内水流流态,取得较好的消能效果.

为解决旋流式溢洪道壁面负压及其产生的空蚀问题,提出一种无通气孔的新型竖井旋流式溢洪道,并通过物理模型试验及数值模拟计算对其消能及空化特性进行研究.研究结果表明:无通气孔竖井旋流式溢洪道利用进水隧洞净空余幅作为掺气设施,使下泄水流卷携大量空气进入竖井内形成稳定掺混空腔,在竖井井壁摩擦剪切作用及旋转水流相互碰撞下,水流紊动加剧,显著提高掺气浓度及能量紊动耗散,有效解决旋流式溢洪道中易出现的空蚀破坏、消能不充分等问题.

角木塘电站最大单宽下泄流量达到211.2 (m3/s) ·m,溢流堰前后最小水头差H仅有5.39m,属于典型的大单宽泄流量、低水头闸坝工程,此类工程往往具有低佛氏数、下游深尾水以及消力池内消能不充分等问题.结合物理模型试验,针对原跌坎消力池内尾水较深、入池水流剪切、摩擦紊动不足、消能效果较差等问题,提出趾墩等常规消能工以及非完全宽尾墩联合辅助消能工,并得出以下结论:非完全宽尾墩利用相邻闸室非对称挑射水舌,增强入池水流横向扩散,加剧消力池内水流紊动,有效调整消力池内下泄水流流场分布,明显消除原设计方案出池水流二次水跃,出池流速由原设计方案7.23 m/s降低至4.43 m/s,校核工况及常遇工况消能率由原设计方案的9.03％和33.03％分别提升至20.47％和58.75％.该方案能取得良好的水流流态和消能效果,可为类似低水头、大单宽流量工程提供参考.

Aimed at the attendant adverse swirl in the front of bottom hole and persistent adverse water-wing outside the bottom hole due to large lateral space between adjacent sluice,this paper comparatively proposes installing oval pier and wedge pier downstream the bottom hole. Results show that wedge pier program can not only adjust velocity distribution to avoid deflected stream in the downstream of open diversion channel,but also meet the requirements of diversion design flood, which will maintain the original cofferdam structure and avoid design alteration to save construction investment.

In order to solve the engineering problems of secondary hydraulic jump and downstream river bed erosion due to insufficient energy dissipation in deep tailwater stilling basin, this paper compares the stilling basin flow fields of flat gate pier, conventional flaring gate pier and incomplete flaring gate pier based on the physical and numerical models. Results show that through increasing velocity gradient and lateral water level gap between adjacent chambers, the incomplete flaring gate pier can promote the lateral diffusion and collision of water jets to form growing vertical vor-tex from bottom to surface in the upper regions of stilling basin. This would significantly intensify energy dissipation to reduce the outgoing velocity, and completely solve the common hydraulic problems in deep tailwater stilling basin.

Located in upstream of Muleng river and arranged with multiple foldback,Fendou fishway is the typical vertical slot fishway with 32.43 m maximum water head and large water level change amplitude.Combined with hydraulic physical model,this paper makes a detailed analysis about hydraulic characteristic inside the fishway under different operation conditions.Results show that the water depth inside the fishway is greatly influenced by water level of downstream outlet:the fluctuation of hydropower station tailwater can significantly increase water depth inside the fishway and impact longitudinal velocity near the vertical slot,which could hinder fish reflux.Through slowing down the longitudinal slope of inlet and adding more baffles,the water depth regions can extend and avoid rapid change of velocity.

Limited by measuring means, the conventional physical model test almost couldn′t comprehensively study the variation of hydraulics parameters in the deep tail water stilling basin.Based on the renormalization group (RNG) k-ε turbulence model and the volume of fluid (VOF) method, the flow field variation in the deep tailwater stilling basin of the flat gate pier program and incomplete flaring gate pier program were respectively studied, and the energy dissipation mechanism of incomplete flaring gate pier was revealed.Research results show that restricted by the longitudinal overflow weir length and the deep tailwater in the stilling basin, the submerged hydraulic jump approaches weir crest in the flat gate pier program, leading to the insufficient energy dissipation turbulence in the stilling basin and strong secondary hydraulic jump outside the stilling basin.The incomplete flaring gate pier program restricts the overflow weir chamber width to result to the longitudinally stretched water jet, and the asymmetric water flow is utilized in the adjacent chamber to enhance the lateral flow velocity gradient and the water level drop.The large vertical axis rolling from the bottom to the surface is created in the upstream region of stilling basin by the intensified latera diffusion and intersection, which significantly enhances energy dissipation in the stilling basin, inducing the flow rate of outlet water and achieving well energy dissipation effect.

青龙RCC拱坝在施工过程中多次调整封拱温度,针对不同的封拱温度方案,利用ANSYS有限元软件计算了温降工况下坝体的应力,并编写APDL程序导出了各方案下上、下游面两拱端及拱冠的等效应力,分析了拉应力的分布规律.结果表明,不同封拱温度方案下青龙拱坝坝体拉应力分布差距较大,当局部高程坝体的实际封拱温度高于设计值时,坝体的拉应力分布范围较设计工况有所扩大,应力值增大;在高温季节施工时,若不采取温控措施,坝体会产生过高的拉应力而影响安全.

Kaléta大坝一期围堰在试验初期过程中发现下游河道泄流能力不足，在上游洪水来流量还未至导流设计标准流量时，堰前水位已达到堰顶高程，为此，以模型试验的方法对比加高围堰方案和扩挖右岸河床方案，通过测量河床泄流能力、分析河道流态论证方案可行性，比选最佳方案，为工程导流设计及防洪度汛提供指导。

A hydraulic model test of the Kaleta stepped overflow dam is carried out, in which the flow pattern, aeration characteristics, water pressure distribution on the dam surface and the energy dissipation ratio of the steps are studied and analyzed systematically.The major impact factors of different hydraulic parameters and their variations are dis-cussed.The study provides a useful reference for the design of stepped dissipater.

过水围堰因其适用范围广且节约资源和工期等优点而被广泛应用,但在大单宽流量条件下,围堰过水后围堰下游防冲难度较大,因而提出在镇墩上加设微型挑角鼻坎的围堰堰后冲刷控制方法,并进行了体型优化模型试验.结果表明,通过控制镇墩上加设的微型挑角鼻坎挑角使出堰主流略微上抬,不仅可以减轻河道底部冲刷和河面波浪,也能使优化体型过水围堰下游面板的脉动压力达到要求,且不会产生空蚀空化及流激振动的问题,还节省了制作铅丝笼的费用,是非常经济实用的体型设置.

多折回通道型同侧竖缝式鱼道水力特性复杂，竖缝流速特性是研究的重点问题。针对多折回通道型同侧竖缝式鱼道进行模型试验研究，系统分析了鱼道竖缝流速特性。试验选择了3组不同流量、水位工况，实测了不同工况下竖缝表面及底部流速沿程分布情况，总结了多折回通道型鱼道在不同通道区段竖缝流速沿程分布规律，分析了影响竖缝流速大小的因素。针对工况3竖缝流速偏大的问题，试验采取了对鱼道边壁加糙的优化设计方案。边壁加糙措施增强了鱼道的消能作用，有效降低了鱼道竖缝流速大小。试验研究成果对类似鱼道工程设计及研究具有很好的借鉴意义。