Benabid Mouna-Keltoum, Baumgartner Peyton, Jin Ge, Fan Yilin
Petroleum Engineering Department, Colorado School of Mines, Golden, CO 80401, USA.
Geophysics Department, Colorado School of Mines, Golden, CO 80401, USA.
Sensors (Basel). 2025 Aug 10;25(16):4937. doi: 10.3390/s25164937.
This study investigates the performance of Distributed Acoustic Sensing (DAS) for detecting gas pipeline leaks under controlled experimental conditions, using multiple fiber cable types deployed both internally and externally. A 21 m steel pipeline with a 1 m test section was configured to simulate leakage scenarios with varying leak sizes (¼", ½", ¾", and 1"), orientations (top, side, bottom), and flow velocities (2-18 m/s). Experiments were conducted under two installation conditions: a supported pipeline mounted on tripods, and a buried pipeline laid on the ground and covered with sand. Four fiber deployment methods were tested: three internal cables of varying geometries and one externally mounted straight cable. DAS data were analyzed using both time-domain vibration intensity and frequency-domain spectral methods. The results demonstrate that leak detectability is influenced by multiple interacting factors, including flow rate, leak size and orientation, pipeline installation method, and fiber cable type and deployment approach. Internally deployed black and flat cables exhibited higher sensitivity to leak-induced vibrations, particularly at higher flow velocities, larger leak sizes, and for bottom-positioned leaks. The thick internal cable showed limited response due to its wireline-like construction. In contrast, the external straight cable responded selectively, with performance dependent on mechanical coupling. Overall, leakage detectability was reduced in the buried configuration due to damping effects. The novelty of this work lies in the successful detection of gas leaks using internally deployed fiber optic cables, which has not been demonstrated in previous studies. This deployment approach is practical for field applications, particularly for pipelines that cannot be inspected using conventional methods, such as unpiggable pipelines.
本研究在可控实验条件下，使用内部和外部部署的多种光缆类型，研究分布式声学传感（DAS）检测燃气管道泄漏的性能。配置了一段21米长的钢管，其中1米的测试段用于模拟不同泄漏尺寸（¼英寸、½英寸、¾英寸和1英寸）、方向（顶部、侧面、底部）和流速（2 - 18米/秒）的泄漏场景。实验在两种安装条件下进行：一种是安装在三脚架上的支撑管道，另一种是铺设在地面并用沙子覆盖的埋地管道。测试了四种光纤部署方法：三种不同几何形状的内部电缆和一种外部安装的直电缆。使用时域振动强度和频域频谱方法对DAS数据进行分析。结果表明，泄漏可检测性受多种相互作用因素的影响，包括流速、泄漏尺寸和方向、管道安装方法以及光缆类型和部署方式。内部部署的黑色扁平电缆对泄漏引起的振动表现出更高的灵敏度，特别是在较高流速、较大泄漏尺寸以及底部位置的泄漏情况下。由于其类似电缆的结构，粗内部电缆的响应有限。相比之下，外部直电缆的响应具有选择性，其性能取决于机械耦合。总体而言，由于阻尼效应，埋地配置中的泄漏可检测性降低。这项工作的新颖之处在于成功地使用内部部署的光纤电缆检测到了燃气泄漏，这在以前的研究中尚未得到证实。这种部署方法对于现场应用是切实可行的，特别是对于无法使用传统方法进行检测的管道，如不可清管的管道。
