影响轴流转桨式水轮机过鱼能力的关键运行参数

Key operation parameters affecting fish passing capability in Kaplan turbines

为减小鱼类在水轮机流道内遭受损伤的概率,提高水轮机过鱼能力,在明确鱼类通过水轮机流道遭受损伤的机理的基础上,结合流道三维水动力分布特性和过机鱼类水动力损伤阈值,构建水轮机流道水动力过鱼能力评价方法。以长江四大家鱼幼鱼通过葛洲坝水电站ZZ500型水轮机流道下行为研究实例,探讨影响轴流转桨式水轮机过鱼能力的关键运行参数。结果表明:轴流转桨式水轮机运行水头、流量、导叶开度、桨叶转角及出力对流道过鱼能力都存在一定影响,关键影响参数为水轮机运行水头和导叶开度。水轮机运行在低水头、大流量、大出力、高效率工况时,流道空间水动力特性对过机鱼体造成损伤的概率较小,流道水动力过鱼能力最强。

In order to reduce the probability of fish injury and improve the fish passing capability for water turbines, an evaluation method for fish passing capability was established based on the fish damage mechanism. Combined with a three-dimensional hydrodynamic distribution characteristic of the turbine passage and the hydrodynamic damage threshold of the fish, the evaluation method was proposed for fish passing ability. The key operation parameters for Kaplan turbines were discussed based on the study case in which the juvenile of the four major Chinese carps in the Yangtze River passing through the ZZ500 turbine passage in the Gezhouba Hydropower Station. The results show that the operating head, flow rate, guide vane opening, blade angle and power output of the Kaplan turbine all have certain influence on the fish passing capability, and the key influence parameters are operating head and guide vane opening. When the turbine operates under the conditions of low head, large flow, large output and high efficiency, the probability of fish injury caused by the spatial hydrodynamic characteristics of the flow passage is small, and the fish passing capacity of the turbine passage is the best.