冲蚀和空蚀交互磨损及其影响因素研究  

Interactive wear of abrasion and cavitation erosion and its influencing factors

作　　者：唐勇[1] 朱宗铭[1] 庞佑霞[1] 梁亮[1] 许焰[1] 李彬[2] 

机构地区：[1]长沙学院机电工程系,长沙410022 [2]湖南科技大学机电工程学院,湖南湘潭411201

出　　处：《水力发电学报》2012年第5期272-277,共6页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金资助项目(50975032);湖南省"十二五"重点学科建设项目资助;湖南省教育厅资助科研项目(10A009)

摘　　要：基于计算流体力学(CFD)方法,数值研究了在模拟水轮机工况下,纯空蚀与冲蚀和空蚀交互作用时,转盘表面上汽液固三相流场及特性,以及空化孔径和孔距对交互作用的影响,并在转盘式磨损装置上,进行了汽液固三相冲蚀和空蚀交互磨损试验。结果表明:数值分析得到转盘表面在纯空蚀与冲蚀和空蚀交互作用下,其压力分布、汽相分布明显不同,在冲蚀和空蚀交互作用下,空化孔附近交互磨损比纯空蚀磨损严重且靠近空化孔,磨损主要发生在有汽相体积比且压力梯度较大的区域;在交互作用下,就某一空化孔而言,磨损区域在空化孔沿转盘旋转方向的孔边成夹角展开为鱼尾形,并且随着空化孔径的增大,磨损加剧,随着孔间距的减小,空蚀部分产生叠加,磨损加剧;从转盘的磨痕区域和磨损程度分析,数值计算结果和试验结果基本相符。Computational fluid dynamics （CFD） method was used to simulate the vapor, liquid and solid phase flow fields of a hydraulic turbine in working condition and to compare the flow behaviors near the turntable surface for the two cases of single cavitation erosion and cavitation-abrasion interactive wears. Influences of cavitation hole diameter and hole spacing on interactive wears were analyzed. Experimental tests of interactive wears in three-phase flow were conducted by using a rotating wearing device. Results show that pressure and vapor distributions on the turntable surface are significantly different in the two cases, and in a region around the cavitation hole, interactive wears are more severe than single cavitation erosion while abrasion often appears in the regions of greater volume fractions of vapor phase and greater pressure gradients. In the region around a certain cavitation hole, under interactive effects abrasion takes a fish-tail shape that expands in a certain angle along the hole edge in the rotational direction. This abrasion is intensified as the hole diameter or the hole spacing is decreased. In the latter case, cavitation erosion is superimposed on abrasion. Numerical calculations agree with the experimental results in terms of wear region shapes and wearing intensity on the turntable surface.

关 键 词：水力学 冲蚀与空蚀 交互磨损 计算流体力学 

分 类 号：TV136[水利工程—水力学及河流动力学]