流激振动对闸门启闭力影响的研究

A reasonable estimation of thegate opening-closing force is an important factor which relates to whether the gate is able to normally operate or not.And whether the gate is able to normally operate or not will directly affect the safe operation of the entire hydraulic structure. At present, the calculation of gate opening-closing force is mainly dependent on the empirical formula, which ignores many factors that impact on the value of the gate opening-closing force, and it is difficult to meet the actual needs of the project. This project study on the impact of the flow-induced vibration on gate opening closing force by theoretical research, numerical simulation and prototype observation. The main contents include: the study of the effect of flow-induced vibration on horizontal-longitudinal load;the effect of horizontal-longitudinal load induced by flow-induced vibration on the gate walking (or rotate) supporting and the relationship between the gate bottom edge of the structural properies and the flow-induced vibration, overcurrent flow pattern and vertical hydrodynamic,respectively.On this basis, fluid-solid coupling model which concerning the effect of flow-induced vibration on horizontal-longitudinal load is established. This model is mainly used to simulate the relationship between the transverse longitudinal flow of flow-induced vibration and opening-closing force. Finally, through the integration of friction model and the fluid-solid coupling model, the simulated mathematics model of gate opening-closing force is put forward.The results of this study will not only substantially increase the level and efficiency of the design of the opening-closing force, but also have important theoretical significance.

闸门启闭力的合理估算是关系到闸门能否正常运行的重要因素，而闸门正常运行与否将直接影响到整个水工建筑物的安全运行。目前闸门启闭力的计算主要依赖于经验公式，其中忽略了许多影响闸门启闭力的因素，难以满足工程实际的需要。本课题将采取理论研究、数值仿真计算以及原型观测与调研相结合的技术方法，深入研究流激振动对闸门启闭力影响。研究内容包括：流激振动对闸门横纵向荷载的影响；流激振动产生的横纵向荷载对行走(或转动)支承摩阻的影响；闸门底缘型式与流激振动、过流流态和垂直水动力之间关系等。在此基础上，建立闸门流激振动对横纵向荷载影响的流固耦合模型，应用该模型模拟流激振动的横纵向响应对闸门启闭力的影响。最后，通过集成摩擦模型和闸门流激振动对横纵向荷载影响的流固耦合模型给出平面闸门、弧形闸门启闭力仿真模拟数学模型。该项研究成果不仅将大幅提高闸门启闭力设计水平和效率，而且也具有重要的理论研究意义。

闸门启闭过程中的振动问题以及由振动引发的闸门启闭力问题，是水工钢闸门在实际运行中常见的工程问题，有效的处理闸门振动与启闭力间的关系对闸门安全稳定运行有着重要作用。本课题分别对平面闸门和弧形闸门在启闭运行过程中的振动和启闭力特征进行研究。对于平面闸门，主要对滑块支承型式和滚轮支承型式两种平面闸门进行物理模型试验，并根据原型平面闸门的动水闭门试验，研究平面闸门启闭过程中的振动与启闭力特性，探究闸门闭门振动的影响因素和形成机制。类比干摩擦自激振动，建立平面闸门的闭门振动模型，探究闸门闭门振动与流激振动的差异。利用平面势流理论建立平面闸门与水流间的动态方程，研究闸门顺水流向振动对闸门面板水压力的影响。研究结果表明，基于势流理论，可以得到的平面闸门振动对面板水压力变化的半经验半理论公式。平面闸门闭门振动试验结果表明，闸门闭门振动的主要影响因素是闸门与轨道间的摩擦特性，平面闸门竖向的闭门振动是一种特殊形式的非线性自激振动现象，闸门竖向水动力载荷对竖向振动起到一定的限制作用。平面闸门在动水启门振动可作为一种辅助证据，证明其闭门振动源自于闸门与轨道间的摩擦因素。然而，在闸门固定开度条件下，闸门振动主要以流激振动形式体现，主要是由水流通道中的涌浪、水击以及闸后剧烈的水流紊动等问题而诱发的闸门顺水流向的振动。对于弧形闸门，利用势流理论得到弧形闸门振动对面板水压力影响的经验公式。采用混沌理论可用于分析弧形闸门面板和支臂在启门和闭门过程中振动的复杂性，指出弧形闸门启门过程振动形式更为复杂。综合平面闸门和弧形闸门在启闭过程中的振动数值模型，利用Fluent中的用户自定义程序，分别建立了两种类型的闸门的流固耦合数值模型。利用数值模型结果，论述闸后的流场特性，阐明了闸门底缘上托力系数的变化特性，构建的闸门闭门持住力的数值模型可以为在设计阶段闭门持住力的计算提供技术支持。