基于双流体模型的人工煤气管道腐蚀预测

Prediction of Corrosion in Artificial Gas Pipelines Based on a Two-fluid Model

人工煤气管网中广泛存在的多相流动腐蚀是造成人工煤气管道减薄的主要原因。针对现有检测技术难以检测输送复杂介质管道的剩余壁厚的问题,以昆明市燃气管网为例,基于双流体模型进行人工煤气管网的多相流动分析,采用实验与理论研究相结合的方法,确定了人工煤气管道的腐蚀特征,计算得到管道的腐蚀情况,结果表明:管道腐蚀程度主要与持液率和CO_2分压相关;采用多相流动仿真模型平均腐蚀速率为0.054 3 mm/a,全动态多相流模拟的腐蚀预测结果存在明显误差;建立的人工煤气管网腐蚀速率预测模型误差平均值为8.9%,优于全动态多相流模拟多相流腐蚀预测结果。

The pervasive corrosion induced by multiphase flow- in artificial gas pipe networks is the main cause of the thinning of artificial gas pipelines. Existing techniques present difficulties for detecting the residual wall thickness of the pipelines used for conveying complex media. Using the gas pipeline network in Kunming as an example, in this study, we performed a multi- phase flow-analysis of the artificial gas pipeline network based on a two-fluid model. By combining experimental and theoretical research methods, we determined the corrosion characteristics of the artificial gas pipeline and calculated the corrosion condition of the pipeline. The results showed that the corrosion degree of pipeline was mainly related to the holdup rate of the liquid and the partial pressure of CO〉 The average corrosion rate calculated by the multiphase flow- simulation model was 0.054 3 mm/a. Significant errors were found in the corrosion prediction results of the full dynamic multiphase flow- simulation. Specifically, the average error of the model established for predicting the corrosion rate of artificial gas pipe network was 8.9 %. This result was superior to the corrosion prediction obtained by full dynamic multiphase flow- simulation.