Duffing振子在长输天然气管道泄漏检测中的应用

Application of Duffing Oscillator on Leak Detection of Long Distance Gas Pipeline

为了及时发现天然气管道泄漏,在管段上下游安装声波变送器,实时获取管道内的声波信号,采用功率谱估计的方法对泄漏声波信号进行分析,可确定泄漏声波频率在16~20 Hz之间。然后分析研究了Duffing振子检测方法中驱动力相位、频率与相轨迹状态之间的关系,并建立了基于Duffing振子的天然气管道泄漏检测系统,通过设置不同的驱动力相位,将管道内声波信号进行频率变换后输入到检测系统可以判断是否存在泄漏声波的频率成分,从而实现天然气管道的泄漏检测;为了验证方法的有效性,在实际天然气管道建立了测试系统,开展了多次不同孔径的管道泄漏测试,将泄漏声波信号输入检测系统,均可检测到泄漏声波;现场测试结果表明该方法对多种孔径的泄漏均具有较好的检测效果,可解决天然气管道较小泄漏的检测问题。

In order to detect the leakage of gas pipeline,acoustic transmitters are installed in the two ends of the pipeline segment to obtain the acoustic signal in the pipe.The frequency of leakage acoustic is between 16~20 Hz which is analyzed by power spectrum estimation method.Then the relationship between Duffing oscillator’s driving force phase,frequency and phase trajectory is analyzed.So a natural gas pipeline leakage detection system based on Duffing oscillator is established.Convert acoustic signal frequency and then input the signal into the Duffing oscillator detection system with different driving force phase can determine whether there is frequency component of leakage acoustic of natural gas pipeline.At last,a test system was established and several tests with different leakage apertures are experimented.The field test results show that the method can detect the gas pipeline leakage of various leakage apertures.