船舶海水管路冲刷腐蚀仿真分析及预测

目的 获取船舶海水管路系统中弯管在不同因素影响下的冲刷腐蚀规律,预测其冲刷腐蚀速率.方法 采用试验测试和数值仿真相结合的方法,研究管路系统中弯管在不同海水流速、管径、弯径比影响下的冲刷腐蚀规律,采用灰色关联分析各因素对冲刷腐蚀影响的严重程度,最后建立冲刷腐蚀速率预测方程.结果 随流速增加,最大冲刷腐蚀速率先增大、后趋于平稳;随管径增加,管壁最大冲刷腐蚀速率逐渐减小;随弯径比增加,管壁最大冲刷腐蚀速率先减小后略有增加.不同因素对冲刷腐蚀速率影响的严重程度由大到小为弯径比、流速、管径.结论 数值仿真方法可快速获取管路参数变化对冲刷腐蚀速率的影响,基于仿真结果建立的冲刷腐蚀速率预测方程可以很好地预测不同因素影响下的弯管冲刷腐蚀,有较高的预测精度.

Simulation Analysis and Prediction of Erosion-corrosion of Seawater Pipelines in Ships

This paper aims to obtain the erosion-corrosion law of the bend in the marine pipeline system under the influence of different factors and predict the erosion-corrosion rate. Based on the combination of test and numerical simulation, the scour corrosion regularity of bend in pipeline system under the influence of different seawater velocity, pipe diameter and ratio of bending radius to diameter is studied. Grey correlation analysis is used to analyze the influence of various factors on erosion-corrosion. Finally, the prediction equation of erosion-corrosion rate is established. With the increase of flow rate, the maximum erosion-corrosion rate first increases and then tends to be stable; with the increase of pipe diameter, the maximum erosion-corrosion rate of pipe wall gradually decreases; with the increase of ratio of bending radius to diameter, the maximum erosion-corrosion rate of pipe wall first decreases and then slightly increases. The sequence of the influence of different factors on the erosion-corrosion rate from high to low is the ratio of bending radius to diameter, velocity and pipe diameter. Numerical simulation method can quickly obtain the influence of pipeline parameters on erosion-corrosion rate. The prediction equation of erosion-corrosion rate based on the simulation results can predict the erosion-corrosion under the influence of different factors and has high prediction accuracy.