丰满水电站重建工程挑流消能方案泄洪雾化研究

Study on flood discharge atomization of ski-jump energy dissipation scheme for reconstruction project of Fengman Hydropower Station

针对丰满水电站重建工程中的挑流消能方案,采用随机溅水数学模型,进行了泄洪雾化降雨数值模拟,将水舌入水喷溅源进行空间离散,描述水舌入水形态对下游雾化降雨的影响,同时考虑飞行水滴与空气间的相对速度,分析了各种泄洪运行方式与自然风场对雾化降雨分布的影响。研究表明:丰满水电站重建工程采用的分区挑流泄洪方案可将雾化区域控制在河道水面范围内,雾化降雨对左岸三期电站、右侧坝后电站、以及右岸生产、生活区的影响有限。在10 m/s以上横向风场作用下,左岸三期电站尾水平台出现5 mm/h左右的降雨,对此可通过增设地面排水设施加以解决。对于泄洪运行调度,建议优先开启中区4~#—6~#溢流表孔,然后是右区7~#—9~#溢流表孔,最后是左区1~#—3~#表孔,这可进一步减轻雾化对两岸建筑物及边坡稳定产生的不利影响。

Aiming at the ski-jump energy dissipation scheme for the reconstruction project of Fengman Hydropower Station, a nu merical simulation on the atomized rainfall caused by flood discharge is made with the stochastic splash model, in which the inflow splashing source of the water nappe is spatially dispersed for describing the impact from the inflow pattern of the water nappe on the downstream atomized rainfall, meanwhile, the relative velocity of the flying water drops to the air is considered and then the impacts from all kinds of flood discharge modes and the natural wind field on the distribution of the atomized rainfall are ana- lyzed as well. The study indicates that the zoned ski-jump flood discharge scheme adopted by the reconstruction project of Fengman Hydropower Station can control the atomization area within the range of the water surface of the fiver channel, thus the impact from the atomized rainfall on the Phase III hydropower plant on the left bank, the right side hydropower plant behind the dam as well as the production and living areas on the fight bank is limited. Under the effect of the transverse wind field of over 10 m/s, the rainfall of about 5 mm/h is to occur at the tailrace platform of the Phase III hydropower plant, which can be solved through adding surface drainage facilities. For the operation of the flood discharge, it is suggested to open the No. 4 N No. 6 overflow sur- face outlets of the central portion preferentially, and then, open the No. 7 ~ No. 9 overflow surface outlets of the right portion, at last, open the No. 1 ~ No. 3 overflow surface outlets; by which the unfavorable impact from the atomization on the structures on both the banks as well as the stability of the slope can be further alleviated.