直角弯管内液固两相流固体颗粒冲蚀磨损分析

Erosion wear analysis of solid particles in liquid-solid two-phase flow of right-angle bend pipe

基于流体力学(CFD)方法,分析了直角弯管的内部流动规律,计算结果表明:直角弯管在90°转角和下游水平管路中存在流动分离现象,同时在下游水平管路中形成明显的二次环流。在流场计算的基础上,引入Tulsa大学冲蚀与腐蚀联合研究中心(E/CRC)提供的冲蚀模型,对直角弯管的冲蚀磨损问题进行研究,分析了固体颗粒的空间分布特征和上下游管壁的最大冲蚀率以及总体质量损失,计算结果与实验数据具有良好的一致性。固体颗粒的空间分布特征依赖于流体流动特性,磨损最严重的位置发生在弯管转角处和下游管路的内侧壁面。流速、颗粒浓度和颗粒直径对最大冲蚀率有明显影响,其中,流速与最大冲蚀率呈指数增长关系,上下游管壁的速度指数分别为2.5和2.3。

Internal flow law of right-angle bend pipe is analyzed base on the CFD method. Calculation results show that flow separation occurs at the 90° corner and in downstream horizontal pipeline and obvious secondary circulation in the downstream horizontal pipeline. Erosion model provided by the Erosion and Corrosion Joint Research Center of Tulsa University （E/CRC） is introduced on the basis of flow field calculation to conduct the research on erosive wear of the right- angle bend pipe, in which spatial distribution characteristics of solid particles as well as maximum erosion rate and overall quality loss of upstream and downstream pipe walls are analyzed to show good consistency between calculation results and experimental data. Spatial distribution characteristics of solid particles depend on fluid flow characteristics and the most serious wear occurs at the bent pipe comer and inside wall surface of downstream pipeline. Flow rate, particle concentration and particle diameter have a significant effect on the maximum erosion rate, of which the flow rate follows an exponential growth relationship so that flow rates of upstream and downstream pipe walls respectively reach the index of 2.5 and 2.3. （1 Table, 10 Figures, 16 References）