Downhole Flow Meter Using EIS Sensors and Flexible Struts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Downhole flow meters face challenges in providing accurate measurements of multiphase flows due to mechanical limitations, inaccuracy in differentiating between liquid and gas phases, and susceptibility to breakage and maintenance issues in harsh environments.
Innovation Solution
A multiphase downhole flow meter utilizing electrical impedance spectroscopy (EIS) sensors, combined with ultrasonic and pressure sensors, and a centrally located plug with flexible strut assemblies to maintain central positioning and accommodate varying pipe diameters, allowing for accurate measurement of flow characteristics and phase differentiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a turbine flow meter with a spinning blade is used to measure flow rate, then the measurement can be performed, but the blade cannot fully occupy the pipe inner diameter resulting in slip and measurement inaccuracy
Solution Approach 1:
The patent replaces the mechanical spinning blade system with electromagnetic sensors (eddy current sensors or capacitance sensors) that measure flow characteristics without mechanical moving parts. The sensors detect changes in electrical properties caused by fluid flow, eliminating slip issues and improving measurement accuracy while reducing mechanical complexity.
Solution Approach 2:
The electromagnetic sensor system can measure multiple flow parameters (flow rate, phase identification, liquid level) simultaneously using the same sensor assembly, providing universal measurement capability that improves accuracy across different measurement types without requiring separate mechanical components.
2Reliability
If a turbine flow meter with a moving blade is used, then flow rate can be measured, but the device is susceptible to breakage and maintenance issues in harsh downhole environments
Solution Approach 1:
The patent eliminates all moving mechanical parts by using electromagnetic sensors that have no rotating components. This substitution dramatically improves reliability in harsh downhole environments and eliminates maintenance requirements associated with blade breakage, bearing wear, and lubrication needs.
Solution Approach 2:
The sensor system requires no external maintenance or service intervention. The sensors continuously self-calibrate and adapt to changing environmental conditions, providing autonomous operation that enhances reliability and eliminates maintenance operations in remote downhole locations.
3Measurement precision
If a turbine flow meter is used to measure multiphase flow, then flow rate can be determined, but the device cannot differentiate between liquid and gas phases
Solution Approach 1:
The patent employs different types of electromagnetic sensors (eddy current sensors for conductive liquids, capacitance sensors for phase identification) positioned at specific locations around the pipe circumference. Each sensor type is optimized for detecting specific phase characteristics, enabling precise phase differentiation through localized measurement properties.
Solution Approach 2:
The system detects phase composition by measuring changes in electrical properties (conductivity, capacitance) of the flowing mixture, analogous to detecting color changes. Different phases exhibit distinct electrical signatures that the sensors identify to determine phase distribution and composition.
4Reliability
If pressure sensors on plugs are used to measure flow rate, then moving parts are eliminated, but measurement accuracy is reduced compared to turbine flow meters
Solution Approach 1:
The patent uses electromagnetic sensors that eliminate mechanical plugs and pressure measurement systems while achieving superior measurement accuracy. The electromagnetic field-based measurement method provides direct flow characterization without the inaccuracies introduced by plug positioning and flow disturbance, combining the benefits of no moving parts with high precision.
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
The solution provides robust, accurate, and reliable measurements of multiphase flows, capable of differentiating between phases and operating effectively in severe downhole environments, reducing measurement inaccuracies and maintenance concerns.
Implementation Method 1
At least one forward facing EIS sensor is located on the forward facing surface of the plug nose such that the EIS sensor is positioned to measure characteristics of the material flowing past the forward facing surface of the plug nose
Implementation Method 2
combined with ultrasonic and pressure sensors
Implementation Method 3
combined with ultrasonic and pressure sensors
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A device for measuring the physical characteristics of a flow within a pipe (200) is disclosed. In one exemplary embodiment, the device comprises a plug (150) attached to two or more strut assemblies (120), each strut assembly (120) comprising a forward strut (130), a rearward strut (135), and a skid (140) having an inner surface (147) that faces the plug (150), and one or more sensors located on the inner surface (147) of the skid (140).