Experimental Investigations on Using Distributed Fiber Sensing for Monitoring Pipelines

Pipeline networks are responsible for transporting vital materials such as water, oil and gas. Complicated loads, material aging, environmental corrosion, and vibration fatigue are the factors which may cause structural deteriorations of pipelines during the life cycle service because of which leaks may arises. Any leakage in the pipeline system can cause major financial losses and possible environmental damages. Currently, buried pipelines are only monitored at key points, which can be spaced several kilometers apart. The use of these discrete sensors for large pipelines is simply impracticable and not cost effective. Distributed fiber optic sensing offers the ability to measure temperatures and strains at thousands of points along a single fiber. DSTS-BOTDA (Distributed Strain and Temperature Sensor-Brillouin Optical Time Domain Analysis) utilizes “stimulated” Brillouin scattering while a DSTS-BOTDR (Distributed Strain and Temperature Sensor-Brillouin Optical Time Domain Reflectometer) utilizes “spontaneous” Brillouin scattering. In this paper, experimental investigations carried out using distributed fiber optic sensing for leakage identification in pipelines is presented. Two different kinds of sensors were used for monitoring strain and temperature variations during leakage. The methodology adopted for instrumentation and the results obtained are presented in detail in this paper.