负压波法在液体管道上的可检测泄漏率分析

由于管道泄漏引发的负压波大小及其沿管道的衰减程度都与管道工况、长度、口径和介质物性等管道特性有关，因此管道特性决定了负压波法在管道上的可检测性。依据特征线理论，对管道的泄漏发生机理和压力波传播机理进行了研究，建立了管道内产生负压波及其传播中衰减程度的计算模型，并利用实际输油管道的操作数据验证了所建立的计算模型的准确性。以该计算模型为基础，进一步分析了管道特性与负压波法的可检测泄漏率等指标的关系，为管道的设计和布局提供参考，并可对基于负压波法的管道泄漏检测系统进行正确的评价。

Analysis on detectable leakage ratio of liquid pipeline by negative pressure wave method

The characteristics of pipeline such as length, diameter, operating conditions and the property of the transferred medium have certain relations with the amplitude and propagation attenuation of the negative pressure wave induced by the leakage of pipeline. Therefore， the pipeline characteristics determine the detectable leakage ratio by the negative pressure wave method for liquid pipeline. On the basis of the Method of Characteristics (MOC) theory, the leakage occurrence mechanism of pipeline and the propagation mechanism of the pressure wave along the pipeline were studied. The computational models were established for generating the negative pressure wave induced by pipeline leakage and for calculating the propagation attenuation of the negative pressure wave along the pipeline. The model for the wave propagation attenuation was validated by the operation data of the real oil pipeline. The experimental results verified the accuracy of the model for calculating the attenuation of the negative pressure wave. The effects of pipeline characteristics on the performance indexes of the negative pressure wave method such as the detectable leakage ratio were analyzed. The computational model can provide some reference for pipeline design and layout. The leak detection system based on negative pressure wave method can be correctly evaluated as well.