弧形闸门前消涡隔栅试验研究

Experimental study on eddy-eliminating barriers mounted on radial gate plate

闸前漩涡是水利工程中常见水流现象,本文通过模型试验和理论分析的方法,采用竖向布置的消涡隔栅对弧形闸门前的漩涡进行了消涡研究。共设计了三种布置方案,分别在闸门迎水面上竖向设置一对、两对和三对消涡隔栅,研究不同开度下,消涡隔栅布置位置、隔栅宽度及隔栅数量对消涡效果的影响。研究表明,竖向布置的消涡隔栅限制了漩涡的旋转回流空间,使漩涡因"伸展不开"而湮灭于水面或缩小为半径较小的漩涡,从而使吸气漩涡区减小,达到消涡目的;三种布置方案中,采用两对消涡隔栅时消涡效果最好;隔栅布置位置和隔栅宽度对消涡效果的影响较大,消涡隔栅布置的最佳位置与闸门宽度有关,消涡隔栅的宽度越大消涡效果越好,但是消涡隔栅宽度的确定还需考虑闸门开度以及实际工程运行工况。本文的研究成果能够为实际工程中泄洪闸门前的漩涡消除提供借鉴。

Vortices often appear in front of water gates of a hydraulic structure. Scale model tests and theoretical analysis have been used in this work to study eddy-eliminating barriers in front of a radial gate, focusing on three schemes of arrangement： one pair, two pairs, and three pairs of fin-shaped barriers mounted on the gate plate. The schemes were compared using different widths and locations of the barriers in the flow condition of different gate openings. The study revealed that the barriers restricted the vortices to limited spaces where they were unable to extend or freely rotate and thus forced to disappear on the water surface or decay into smaller vortices. As a result, the barriers reduced the air-entraining vortex zone so that the goal of eddy-elimination was achieved. Of the three schemes, the arrangement of two pairs is the best. The width and location of a barrier significantly impact its eddy-eliminating effect. In general, the optimal location depends on the gate width and a wider barrier achieves better effect. However, design of barrier width should take into account the gate openings and real gate working conditions.