摘要
为了明确轴流式水轮机泥沙磨损特性,以某电站水轮机为研究对象,基于欧拉-拉格朗日多相流模型开展了固液两相流动数值研究,重点关注泥沙粒径对机组过流部件表面侵蚀率和侵蚀分布的影响.研究发现,叶片正、背面轮缘附近为泥沙磨损高风险区.随着泥沙粒径增大,叶片正面侵蚀程度加剧,背面侵蚀程度减小,磨损区域逐渐集中在轮缘附近;颗粒受泄漏涡影响在转轮室壁面形成沿旋转方向的条状侵蚀痕迹;尾水管锥管段侵蚀率逐渐降低,不同出口流道磨损程度的差异性增大,泥沙颗粒在锥管段形成沿泄漏涡延伸方向的带状螺旋侵蚀痕迹.在运行过程中,磨损程度最大的部件是尾水管,其次为转轮和转轮室,应避免机组长时间在过小或者过大泥沙粒径条件下运行,检修时应重点关注转轮叶片和转轮室的泥沙磨损情况.研究归纳出轴流式机组运行过程中的泥沙磨损高风险区,可为水轮机各过流部件泥沙磨损的定量分析提供一定参考,有助于合理安排机组检修周期,同时为轴流式水轮机进一步优化设计提供理论基础.
To understand and clarify the sediment wear attributes of Kaplan turbines,a certain power station turbine was taken as the research object,and a numerical investigation of solid-liquid two-phase flow was carried out based on the Eulerian-Lagrangian multiphase flow model.The central focus centered on elucidating the influence of sediment particle size on both erosion rate and distribution across the turbine components.Research findings show that the high-risk region for sediment erosion is near the wheel rim of the blade pressure side and the suction side.With increasing sediment grain size,erosion intensifies on the blade pressure side while diminishes on the suction side,leading to a gradual contraction of this erosional region towards the proximity of the wheel rim.Particles are influenced by the leakage vortex,forming strip-shaped erosion scars along the rotation direction on the wall of the runner chamber.The erosion rate gradually decreases in the draft tube cone section,the differences in the degree of wear in different outlet flow passages increase and the sediment particles form belt-like spiral erosion scars along the extension direction of the leakage vortex in the cone section.During the Kaplan turbine operation,the draft tube section experiences the most substantial erosion followed by the runner and the runner chamber.Prolonged turbine operation under conditions of excessively small or large sediment diameters should be avoided,and during maintenance,particular attention should be paid to the sediment wear of the runner blades and the runner chamber.By identifying high-risk region of sediment erosion during the operation of the Kaplan turbine,a reference is provided for the quantitative analysis of sediment wear in various flow passage components.It helps in scheduling maintenance intervals for the turbines and provides a theoretical basis for further optimization in the design of Kaplan turbine.
作者
王彤
李晓飞
郭鹏程
张健
范文睿
陈红吉
WANG Tong;LI Xiaofei;GUO Pengcheng;ZHANG Jian;FAN Wenrui;CHEN Hongji(CHN Energy Dadu River Maintenance and Installation Co.,Ltd.,Chengdu,Sichuan 610041,China;School of Water Resources and Hydroelectric Engineering,Xi′an University of Technology,Xi′an,Shaanxi 710048,China)
出处
《排灌机械工程学报》
CSCD
北大核心
2024年第8期802-809,共8页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家自然科学基金资助项目(51839010)
中国博士后科学基金资助项目(2021M702641)
国能大渡河检修安装有限公司科技项目(JX-KY-2022-03)。
关键词
轴流式水轮机
泄漏涡
固液两相流
泥沙磨损
Kaplan turbine
leakage vortex
solid-liquid two-phase flow
sediment wear
