【作者】 李树宁；

【导师】 杨敏；

【作者基本信息】 天津大学 ， 水利水电工程， 2012， 博士

【摘要】 近年来，随着我国社会经济的发展，人们的环保意识和对生态环境的要求也随之提高，水电工程建设对生态环境的影响成为工程可行性的制约条件之一。人们对水电工程建设的认识和关注发生了改变，不再是仅仅停留在巨大的经济效益上，而是综合考虑了项目建设对生态环境的影响。在此基础上，提出了一种应用于高水头、大单宽流量工程的新型的消能工跌坎消力池。跌坎消力池作为高坝泄洪时的消能建筑物，其自身的稳定性不论对消能防冲还是整体水工结构的安全都具有重大意义。本文基于某水电站溢洪道消力池的模型试验研究，结合理论分析、模型试验和数值模拟的方法，对跌坎消力池底板的水动力荷载特性进行了研究。主要研究成果及结论如下：（1）运用动量定理和能量方程，推导出了突扩型跌坎消力池第一临界水深（发生面流时的最小下游水深）的理论计算公式。基于模型试验与数值计算，得出跌坎消力池流态演变的第一、第二临界水深经验计算公式，可以用来评估类似工程的流态。（2）基于模型试验和数值计算，分析比较了跌坎消力池与传统消力池的临底流速分布以及最大流速分布特性，得出了跌坎型消力池最大临底流速较传统消力池显著降低的指标；研究了跃首流速、跌坎高度、入池能量、入池角度对跌坎消力池最大临底流速的影响，得出了跌坎消力池最大临底流速与跌坎高度、入池能量的经验公式。（3）基于模型试验实测的传统消力池与跌坎消力池中的动水压强，分析得出了跌坎消力池较传统消力池脉动压强显著降低的指标；分析了脉动强度、空间积分尺度、概率密度以及频谱特性；得出了跌坎高度变化时估算消力池底板最大脉动压强的经验公式。（4）基于模型试验成果，研究了传统消力池和跌坎消力池板块所受上举力，分析了跌坎高度、板块尺寸、开孔率对底板上举力的影响，得出了最大上举力的预报经验公式；研究了陡槽末端水跃区底板的上举力以及错台对其的影响，得出了错台对上举力影响的指标。（5）经过一系列不同跌坎体型的消力池水动力学试验，为梨园水电站工程优化出了一种结构较优的跌坎消力池体型，降低了消力池里临底流速、脉动压强、上举力等指标。更多还原

【Abstract】 In recent years, with the great development of society and economy, as well asthe improvement of people’s awareness of environmental protection and therequirements of ecology and environment, the influence of hydraulic engineeringconstruction on ecological environment has become one of the engineering feasibilityconstraints. People’s awareness and concern for the construction of hydropowerprojects is no longer merely the huge economic benefits, but considering the impact ofconstruction projects on the ecological environment. On this basis, stilling basin withdrop sill was proposed as a new energy dissipator which can be used in high-head,large-unit discharge engineering. As an energy-dissipator of downstream bed, thestability of stilling basin with drop sill was of great significance to both the energydissipation and the overall safety of the hydraulic structures. In this paper, based onthe model tests, numerical simulation and theoretical analysis, the characteristics ofhydrodynamic load in stilling basin with drop sill were studied. The main results andconclusions are as follows:(1)Basedon momentum theory and energy equations, the first critical depthformula was derived in stilling basin with drop sill and sudden expansion. Other more,the first and second critical depth empirical formulas were brought forward accordingto the results of numerical simulation and the model tests in stilling basin with dropsill. The formulas could be used to assess the flow pattern of similar projects.(2)Basedon the model tests and numerical calculation, the underflow velocitydistribution and the maximum velocity distribution characteirstic were comparedbetween the stilling basin with drop sill and the routine stilling basin. The index thatthe stilling basin with drop sill can effectively reduce the underflow velocity wasobtained.The influence of drop sill height, inlet energy and inlet angels on themaximum underflow velocity was investigated. The maximum underflow velocityformula was obtained as drop sill height or inlet energy changed.(3)Based on the model tests, the index that the stilling basin with drop sill caneffectively reduce the fluctuating pressure significantly was obtained. The distributionlaw, the probability characteristics, the cross correlation characteirstics and thespectrum characteristics of fluctuating pressure acting on chute slab and stilling basin slab were analyzed. The empirical formula of the maximum fluctuating pressure was obtained as drop sill height changed.(4) Based on the model tests, the uplift on slab was investigated between the stilling basin with drop sill and the routine stilling basin. The influence of drop sill height, slab size and pervious coefficient on the uplift was analyzed. The forecast formula of the maximum uplift was obtained. The uplift on chute slab in the jump region and the influence of the irregularity height on it were researched. The index of the influence of the irregularity height on uplift was obtained.(5) A new type of stilling basin with drop sill was put up for Liyuan Hydropower Project through a series of hydrodynamic test on different stilling basins with drop sill,which reduced the various hydraulics indicators of stilling basin, such as the underflow velocity, the fluctuating pressure, uplift and so on.更多还原