摘要
工作在固液两相流条件下的水力机械部件普遍存在程度不一的磨损破坏,这种破坏主要是过流介质中固体颗粒对部件表面的冲蚀磨损的作用结果。本文应用高速摄影技术,全面追踪和研究了离心泵叶轮流道内固液两相流中固体颗粒的运动轨迹及规律、特别是固体颗粒与过流部件的瞬间撞击过程,系统研究了固体颗粒的粒径大小、密度、进口参数以及运行工况（流量和叶轮转速等）对颗粒运动轨迹的影响规律。固体颗粒对过流部件的冲击破坏作用主要发生在叶片工作面,质量较大的硬质颗粒主要对叶片头部区域产生高角度（60°-90°）的撞击,冲蚀破坏作用较大;质量较小的颗粒主要对叶片工作面的中后部区域产生低角度（20°-50°）的撞击,其破坏作用相对较弱。发生在这两个区域的撞击过程也存在很大的差异,颗粒撞击叶片头部后直接反射回来,与叶片中后部撞击后存在颗粒在壁面上的相对滑动过程。
There is different wear damage universally existing on surface of hydraulic machinery which works in solid-liquid two-phase flow condition. The impingement bctween solid particles and machine surface plays important role in this kind of erosion wear. High-speed photography technique is applied to track and to research the motion lines and motion rules of solid particles in a two-phase flow（solid-fluid）. The instant impingement process between solid particles and machine surface is investigated in detail in this experiment. The influence of density, diameter, inlet velocity and angle of solid particle and rotational speed of impeller on the motion lines of solid particles are obtained finally. Based on the experiment result, the erosive wear resulted from impact process between solid particles and machine surface usually takes place on the working surface of impeller. The solid particles with big mass and high hardness prefer to impact the head area of impeller on high impingement angle （60° - 90°） . The solid particles with small mass and low hardness prefer to impact the middle and tail work surface of impeller on lower impingement angle （20°- 50°）. The instant impingement progress between solid particle and rotational machine surface is different with the impingement progress between solid particle and stationary wall. There is a longtime sliding progress between solid particle and rotational machine surface after impact, especially the impact process between particles and the middle and tail work surface of impeller.
出处
《水力发电学报》
EI
CSCD
北大核心
2008年第6期168-172,167,共6页
Journal of Hydroelectric Engineering
基金
国家自然科学基金(50779079)
国家863项目(2001AA333030)
清华大学基础研究基金(200307007)
关键词
水力机械
固液两相流
离心泵
高速摄影
冲击角度
hydraulic machinery
solid-liquid two-phase flow
centrifugal pump
high-speed photographytechnique
impingement angle
