腐蚀挂片监测有效性主控因素分析

Analysis of the Main Controlling Factors for the Effectiveness of Corrosion Coupon Monitoring

为了分析挂片腐蚀监测有效性的主控因素,采用了多相流腐蚀环道(MPFC)设计覆盖站场工况的三因素三水平正交试验,并运用Fluent有限元模拟分析验证正交试验。多相流腐蚀环道试验得到挂片平均腐蚀速率与温度、流速、安装深度呈正相关,出现挂片腐蚀速率均大于管壁腐蚀速率的现象。Fluent有限元仿真模拟中,挂片表面流速和绕流区域长度与挂片深度呈正相关。湍流动能沿水流方向(x轴方向)呈现先快速增大、后逐步减小的变化趋势。除此之外,挂片的剪切力和腐蚀监测误差均与温度、流速、安装深度呈正相关。最终根据正交试验分析结果,得到挂片腐蚀监测有效性的主控因素排序为安装深度>流速>温度。

To analyze the main factors controling the electiveness of corrosion coupon monitoring,a three-factor,three-level orthogonal exper.iment covering feld conditions was designed using a multiphase fow corosion loop(MPFC).The orthogonal experiment was verified through Fluent finite element simulation analysis.The MPFC tet results indicated that the average corosion rate of the coupons was positively correla ted with temperature,fow rate and instalation depth,and it was observed that the corrosion rate of the coupons was higher than that of the pipe wall.In the Fluent fimite element simulation,both the surace fow velocity on the coupon and the length of the recirculation zone were positivel correlated with coupon depth.Turbulent kinetic energy along the flow direction(x-axis)showed a paem of rapid increase followed by gradual decrease.Additionally,the shear force on the coupon and the corrosion monitoring eror were positively correlated with temperature,flow rate and installation depth.Based on the results of the orthogonal experiment analysis,the controlling factors for the elfectiveness of corrosion cou.pon monitoring were ranked as installation depth>flow rate>temperature.