Multiphase Flowmeter Using Ultrasonic and Microwave Sensing

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing multiphase flowmeters struggle to accurately measure the flow rates of oil, gas, and water in multiphase flows due to varying flow regimes and high gas volume fractions, leading to inaccurate phase fraction measurements and operational limitations, especially at low gas volume fractions where liquid layers become thick, preventing light transmission and causing errors in water-to-liquid ratio estimation.

Innovation Solution

A method and multiphase flowmeter that measures the thickness and axial velocity of the liquid phase, combines these measurements with permittivity data to derive the liquid phase permittivity, and uses relationships between single-phase and two-phase properties to calculate the water-to-liquid ratio, allowing for accurate measurements across a wide range of gas volume fractions without gamma rays, employing ultrasonic and electromagnetic sensors for precise data acquisition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If optical systems using light transmission are used to measure water content and flow rates, then measurements can be obtained for flow regimes with high gas volume fractions, but the system fails when liquid layers become thick and prevent light transmission

Engineering Contradiction:

Improvewater content measurement accuracyVSAvoidapplicability across different flow regimes

Core Design Contradiction:

Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent replaces optical measurement systems with electromagnetic sensing systems that use microwave radiation. This substitution allows the system to penetrate thick liquid layers that block visible light, enabling measurements across all flow regimes including those with low gas volume fractions where optical systems fail.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the measurement parameter from optical transmission to electromagnetic permittivity and conductivity measurements. By measuring the complex permittivity of the multiphase mixture and using mixing rules, the system can determine water fraction, oil fraction, and gas fraction without being limited by liquid layer thickness.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If electromagnetic probes are used to measure mixture permittivity and conductivity, then water fraction can be estimated, but at high gas volume fractions the probe measures both liquid and gas properties providing erroneous results

Engineering Contradiction:

Improvewater fraction estimation accuracyVSAvoidmeasurement accuracy at high gas volume fractions

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent employs a measurement system that simultaneously measures both permittivity and conductivity of the multiphase mixture. By using both parameters together with appropriate mixing rules, the system can reliably determine phase fractions across the entire range of gas volume fractions, including high GVF conditions where single-parameter measurements fail.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Adaptability or versatility

If gamma rays are used for measurement, then accurate readings can be obtained across all flow regimes, but the system becomes complex and requires radiation safety measures

Engineering Contradiction:

Improvemeasurement capability across all flow regimesVSAvoidsystem complexity and safety requirements

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent replaces complex gamma-ray measurement systems with simpler electromagnetic sensing systems using microwave technology. This substitution eliminates the need for radiation safety infrastructure while maintaining the capability to measure across all flow regimes, significantly reducing device complexity and operational constraints.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Enables accurate measurement of flow properties over a wide range of gas volume fractions, from 0% to >99%, providing precise water and oil flow rates without gamma rays, improving measurement robustness and reducing errors associated with thin liquid layers and high gas fractions.

Implementation Method 1

measuring a permittivity of a portion of the multiphase fluid

Methodology Applied

Scientific EffectPermittivity measurement: Dielectric Permittivity

Implementation Method 2

measuring a thickness of the liquid phase

Methodology Applied

Scientific EffectUltrasonic measurement: Ultrasound

Implementation Method 3

measuring an axial velocity of the liquid phase

Methodology Applied

Scientific EffectDoppler ultrasound: Doppler Effect

Data Source

PatentUS8555729B2Method of measuring flow properties of a multiphase fluid

Publication Date: 2013.10.15 SCHLUMBERGER TECH CORP

AI summary

A method and system for measuring a property of a multiphase fluid comprising a mixture of at least an oil phase and a water phase travelling through a conduit, the method comprising measuring the thickness of the liquid mixture, measuring the permittivity of a portion of the multiphase fluid, combining the thickness measurement with the permittivity measurement to obtain a derived value for the permittivity of the liquid mixture, and using at least the derived permittivity of the liquid mixture and a relationship between a single phase liquid property and a corresponding two-phase property of the liquid mixture, to obtain a calculated water-to-liquid ratio of the liquid mixture.