窄缝空化诱发高水头船闸阀门自激振动机理研究

针对贵州清水江流域高水头船闸面临的运行安全问题和高水头船闸阀门顶止水频繁水力破坏而无计可施的现状，开展窄缝射流空化诱发止水强烈自激振动机理及防治技术研究十分迫切。本项目拟通过研发无缩尺影响的顶止水1:1切片试验技术，研究揭示阀门小开度顶止水强烈自激振动与非稳定射流空化相互作用机理；基于不同水压条件下止水的变形特性，提出融入止水体积变形的材料非线性本构模型，建立缝隙非稳定空化流-大变形止水流固耦合振动分析方法，预测止水自激振动应力与寿命周期；通过止水自激振动各种影响因素系统性的试验研究和数值仿真研究，揭示止水的临界失稳条件和不稳定区间，构建自激振动与顶止水动力特性、窄缝宽度、流速、下游压力间的内在关系；提出抑制顶止水不稳定空化与自激振动的自然通气新技术，通过论证并优化后达到工程应用的条件。研究成果将为顶止水结构优化、寿命周期预测、空化与自激振动防治提供科技支撑。

In view of the safety problem of high head ship lock in Qingshui River basin and the practical condition of valve top seal hydraulic damage of high head ship lock without effective measures, it is very necessary to carry out the study on self-excited vibration mechanics and control technology of valve seal induced by narrow slit jet cavitation with the super high head and large scale development of ship lock. In this program, the new 1:1 slice test technology of top seal without scale effect will be proposed to study the interact mechanics between the severe.self-excited vibration of the top seal and unstable jet cavitation in the small opening of the valve. Based on the deformation of the top seal under different water head, material nonlinear constitutive model will be formulated considering the volume deformation. The flow-structure interaction numerical analysis method will be built involving the nonlinear and large deformation characteristics of the top seal to predict the self-excited vibration stress and the seal life. Both systematical tests and numerical simulations of the influence factors to the self-excited vibration will be conducted to reveal the critical instability condition and unstable region and construct the inner relationship between the.self-excited vibration and dynamic characteristics, narrow slit width, flow velocity, downstream pressure and so on. The new technology of natural aeration of the top seal will be proposed to control the cavitation and self-excited vibration. It will achieve the demand of project application after demonstration and optimization. The research results will be benefit for the optimization of the seal structure, prediction of the seal life and the control of the cavitation and self-excited vibration.