Fiber optic sensing (FOS) technology has evolved rapidly in recent years and now offers impressive new capabilities for detecting and analyzing a broad range of integrity phenomena relevant to various industries. The next generation of FOS systems relies on specialty engineered sensing fibers specifically designed to overcome the well-known limitations of telecommunications fibers. These new fiber designs, combined with sophisticated machine learning software, enable precise monitoring of parameters such as temperature, strain, and pressure in near real-time via a single fiber.
In this article, our experts explain the key characteristics of distributed fiber optic systems – both old and new – that set these apart from traditional monitoring technologies to power today’s cutting-edge sensing systems.
1. Distributed Sensing
As the name implies, the most fundamental attribute of distributed fiber optic sensing (DFOS) is the ability to make use of the entire length of the optical fiber, effectively capturing and locating the source of anomalies at any point in space and time along the full fiber path. In sharp contrast to point sensors, this distributed sensing capability allows for continuous monitoring of environmental factors along extensive distances, making the technology invaluable for integrity applications supporting long linear infrastructure.
Traditional sensing systems using telecommunications fiber leverage Brillouin, Rayleigh and Raman scattering to measure strain, temperature, and pressure with limited accuracy depending on the application. Recently, next-generation DFOS systems have emerged that employ custom fibers specifically designed for sensing that overcome some of the well-known limitations of telecommunications fibers – notably low signal-to-noise ratio (SNR). These newer technologies are seeing strong commercial adoption in industries such as pipeline monitoring, where their ability to reliably detect even pin-hole level leak events over vast monitoring networks brings tremendous value.
2. Robust & Reliable
Despite the seeming fragility of the thin glass strand at the core of optical fibers, once packaged for deployment these architectures are staggeringly durable, with decades-long lifetimes designed to match or exceed those of their host assets. Furthermore, the inert nature and electrochemical stability of optical fibers allow them to perform without degradation in harsh conditions where traditional monitoring methods fall short.
Specific examples where fiber-optic sensors monitor well integrity in high-temperature downhole environments for multi-year programs, or measure discharge events for transformers where electromagnetic interference would otherwise compromise the results highlight this robustness and versatility that makes DFOS systems indispensable in aerospace, defense, and industrial applications.
3. Integrated Measurement
In contrast to traditional fiber optic sensors that generally focus on delivering a singular measurement – like Distributed Acoustic Sensing (DAS), Distributed Temperature Sensing (DTS) and Distributed Strain Sensing (DSS) – next-generation technologies are configured to provide integrated measurement of acoustics, temperature and strain via a singular sensing fiber.
The benefits of integrated measurement are substantial; beyond the obvious commercial value in expanding the range of end uses and applications, integrated measurement also dramatically increases the accuracy and reliability of DFOS systems by enabling corroborative validation of event signatures. For example, even tiny leaks generally exhibit multiple energy signatures including acoustics (the hiss of a leak), strain (pipe movement due to leak forces acting on the pipe body) and even thermal (Joule Thomson effects associated with expansion of gases) characteristics that can be cross-referenced to dramatically improve confidence in algorithm (AI/ML) performance. To put it simply, if something sounds like a leak there’s still a good chance it could be something else, but if it sounds, moves and feels like a leak, we’re almost certain that’s what it is.
4. Advanced Software in Sensing
In addition to the physical sensors that we’ve focused on for this blog, advanced hardware and software play a critical role in interpreting the data collected by DFOS systems. High-performance computers (HPCs) with onboard graphical processing units (GPUs process the digital signals from the sensors, supported by customized machine learning algorithms that enhance accuracy and predictive capabilities. This ‘digital brain’ brings remarkable horsepower, transforming raw data into actionable insights, enabling proactive maintenance and reducing the risk of failures while virtually eliminating errors (or false positives) via corroborative validation as noted above. The result is technology with unparalleled monitoring capabilities that safeguards your assets while protecting your bottom line.
Explore Next-Generation Fiber Optic Sensing with Hifi
At Hifi, we’re spearheading the evolution of cutting-edge fiber optic sensing. Our technology combines state-of-the-art sensing fiber with advanced AI/ML software to deliver unparalleled performance in monitoring and analysis.
Contact us today to learn how our High-fidelity Distributed Sensing (HDS™) systems can protect your assets with unmatched precision.