Downhole Fiber Optic Sensor White Light Interferometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing downhole interferometers with fragile components are not robust enough for directional drilling, requiring separation of components above ground, which limits drilling operations and data collection.
Innovation Solution
A compact and robust downhole fiber optic system with an integrated interferometer that includes a light source, interferometer, and detection electronics, using white light and fiber optic sensors to collect data directly downhole, eliminating the need for a fiber optic cable from the surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If interferometer components are placed downhole for direct measurement, then measurement precision and data collection capability improve, but device reliability deteriorates due to fragile components in harsh environment
Solution Approach 1:
The patent replaces traditional mechanical interferometer components with fiber optic-based sensing elements that are inherently more resistant to harsh downhole environments. The fiber optic sensor uses optical interference principles without requiring fragile mechanical moving parts, thus maintaining measurement precision while improving reliability in high-temperature and high-pressure conditions.
Solution Approach 2:
The invention changes the operating parameters of the interferometer by using broadband light sources and optical frequency domain reflectometry techniques that are better suited for downhole conditions. This allows the system to maintain interference measurement capability while operating reliably in environments with temperatures up to 150°C and pressures up to 15,000 psi.
2Reliability
If interferometer components are separated and maintained topside, then device reliability improves by avoiding harsh downhole environment, but device complexity increases due to fiber optic cable requirements and operational limitations
Solution Approach 1:
The patent merges the interferometer components, light source, and detection electronics into an integrated downhole assembly. This eliminates the need for long fiber optic cables running from surface to downhole, simplifying the system configuration and removing operational limitations while maintaining reliability through robust component design.
Solution Approach 2:
The integrated downhole interferometer system is designed to perform multiple functions including formation evaluation, fluid characterization, and downhole condition monitoring. This multi-functionality reduces the need for separate specialized equipment, thereby simplifying overall system complexity while improving reliability through a unified robust design.
3Measurement precision
If traditional interferometers are used downhole, then measurement capability is maintained, but productivity decreases due to frequent maintenance and operational limitations
Solution Approach 1:
The patent employs a robust downhole interferometer design that can operate in harsh conditions for extended periods without maintenance. The fiber optic components and integrated electronics are designed to withstand downhole environments, effectively creating a maintenance-free measurement system that improves drilling productivity by eliminating tool retrieval and replacement operations.
Solution Approach 2:
The invention uses broadband light sources and enhanced signal processing techniques that provide measurement capabilities exceeding traditional interferometers. This excessive action in terms of optical bandwidth and signal processing ensures reliable measurements throughout the entire drilling operation without requiring intermediate maintenance, thereby improving overall productivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution provides rapid, reliable, and versatile data collection, reducing maintenance costs and enabling more comprehensive downhole analysis while withstanding harsh drilling environments.
Implementation Method 1
an electromagnetic energy emitter coupled to the carrier; and a fiber optic sensor that receives electromagnetic energy emitted from the electromagnetic energy emitter
Implementation Method 2
Fiber optic sensor system using white light interferometry
Data Source
AI summary
A downhole fiber optic apparatus for acquiring downhole information includes a carrier conveyable in a borehole, an electromagnetic energy emitter coupled to the carrier, and a fiber optic sensor that receives electromagnetic energy emitted from the electromagnetic energy emitter and generates an optical output signal representative of the downhole information. A method for acquiring downhole information includes conveying a carrier in a borehole, emitting electromagnetic energy from an electromagnetic energy emitter coupled to the carrier, receiving electromagnetic energy emitted from the electromagnetic energy emitter with a fiber optic sensor, and generating an optical signal representative of the downhole information using the fiber optic sensor.