三峡大坝导流底孔闸门流激振动水弹性模型试验研究

 为了解决三峡大坝导流底孔弧形闸门的流激振动问题,采用完全水弹性相似模型研究了闸门的流激振动。介绍了闸门振动水弹性相似原理、水弹性相似材料的性质、闸门水弹模型模态分析及模型振动试验结果。试验结果表明:闸门在无侧止水或侧止水损坏情况下淹没出流时，将产生强烈的自激振动;闸门两侧缝被封堵以后，在同样的淹没出流情况下，只产生轻微振动;闸门产生强烈振动的主要原因是闸门侧缝射流和下游紊动水流汇合后在门侧形成了自激振荡系统的结果;消除侧缝射流，就可以避免强烈的自激振动。

Study on vibration of bottom outlet gate for Three Gorges Project by hydroelastic model

For solving the potential flow induced vibration problem of the tainter gate located at the bottom outlet of the Three Gorges Project,the study on these problems was performed by a perfect hydroelastic model.The hydroelastic similarity criteria,the properties of the newly developed hydroelastic material,the results of mode analysis of the gate and the results of the model test are presented in the paper.It was found that in the scale model investigation severe self excited vibrations take place when the gate is partially submerged by the tailwater level under no side seals(or the side seals being damaged) condition.However,when both side gaps of the gate are blocked from upstream to eliminate the gap jet flow,the gate only suffered weak vibrations.The cause of severe vibration is the formation of a self excited vibrating system by the coaction of the gap jet and turbulent flow downstream the gate.When the gap jet is eliminated by seals the severe self excited vibration doesn't occur.