恒压型边界液体管道泄漏信号检测仿真研究

Simulation Study on Leakage Signal Detection of Liquid Pipeline under Constant Pressure Boundary

在液体管道泄漏检测中恒压型边界产生的反射波会对泄漏直接波造成干扰,掩盖泄漏压力信号的动态特征,从而对后续信号分析造成不利影响。针对这一问题,应用理论分析与仿真相结合的方法,首先分析了恒压型边界反射波的特点及其对测量信号的干扰机理,提出了有效测量信号的概念;然后分析了测量点位置与信号采样频率等因素对测量信号的影响,明确了这些因素与有效测量信号特征的关系;最后有效测量信号、恒压型边界的反射特性及压力波传播规律实现了一种在测量信号中提取直接波信号的方法。研究表明:在恒压型边界条件下可以提取压力测量信号中一定时长的直接波信号,从而克服由于反射波干扰造成的不利影响。

In the liquid pipeline leakage detection, the reflection wave generated by the constant pressure boundary can cause interference to the direct wave, which can cover the dynamic charaeteristies of the pressure signal and will cause adverse effects on subsequent signal analysis. To solve this problem, firstly we analyzed the characteristics of the reflected wave and the interference mechanism, and put forward the eoneept of effective measurement signal. Then, the influence of the factors such as measurement point position and signal sample frequency on the measurement signal was analyzed, and the relationship between these factors and the effective measurement signal was clarified. Finally, a method of extracting the direct wave signal in the measurement signal was realized based on the effective measurement of the signal, the reflection characteristic and the pressure wave propagation law. The research shows that in the constant pressure boundary condition, the direct wave signal within a certain length of time can be extracted from the pressure measurement signal, so as to overcome the adverse effect caused by the interference of the reflected wave.