弯管与盲通管冲蚀磨损对比分析研究

摘要

Aiming at the problem of erosion wear in the position with sharp change of flow direction in oil pipeline, the numerical simulation was carried out on the flow field distribution and erosion situation of 90° elbow pipe and blind tube by using DPM model with changing the inlet velocity, particle mass flow rate and particle diameter.The results showed that the maximum erosion rates of elbow pipe and blind tube increase exponentially with the increase of inlet velocity, and they increase linearly with the increase of particle mass flow rate.The maximum erosion rates decrease gradually with the increase of particle diameter in the range of 50-100 μm, and they increase with the increase of particle diameter in the range of 100-300μm.Under the conditions of the same inlet velocity, particle mass flow rate and particle diameter, the maximum erosion rate of elbow pipe is significantly higher than that of blind tube, and the corrosion resistance of blind tube is better.Due to the vortex phenomenon of fluid in blind tube, the dissipation of particle energy increases, thereby the velocity of particles flowing into the downstream pipe decreases, which makes the particles more likely to accumulate in the blind tube section and form accumulation layer, thus the erosion rate of downstream pipe decreases.%为了研究石油管道流向急剧改变处的冲蚀磨损问题,采用DPM模型,通过改变入口流速、颗粒质量流速、颗粒直径,对90°弯管与盲通管的流场分布及冲蚀情况进行数值模拟.结果表明:弯管与盲通管最大冲蚀速率随入口流速的增大呈指数增长,随颗粒质量流速的增大呈线性增长;在50~100 μm粒径范围内,最大冲蚀速率随粒径的增加逐渐减小,在100~300 μm粒径范围内,随粒径的增加而增大;在入口流速、颗粒质量流速、颗粒直径相同的条件下,弯管最大冲蚀速率明显高于盲通管最大冲蚀速率,盲通管的耐蚀性更强;由于流体在盲通管产生涡旋现象,增加了颗粒能量的耗散,从而减小了进入下游管线颗粒的速率,使得颗粒更易积存于盲通段形成堆积层,减小了下游管段冲蚀速率.