Multicomponent Fluid Density Measurement Using Multi-Mode Vibration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vibrating fluid meters, such as Coriolis mass flow meters, face significant accuracy degradation when measuring multicomponent fluids containing both compressible and incompressible components, particularly due to decoupling effects from entrained gas bubbles, which lead to incorrect density measurements and inaccurate determination of individual component flow rates.

Innovation Solution

A method and system that involves measuring the density of a multicomponent fluid at two different states, adjusting the fluid's density using a density adjustor to maintain the same mass proportion of components, and using Coriolis flow meters to determine fluid characteristics, allowing for accurate measurement of incompressible and compressible components' properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a vibrating fluid meter is used to measure multicomponent fluids with entrained gas bubbles, then the meter can handle a wider range of fluid types, but the measurement accuracy is significantly degraded due to decoupling effects

Engineering Contradiction:
Improveability to measure multicomponent fluidsVSAvoiddensity measurement accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent segments the multicomponent fluid measurement problem into separate measurements of the liquid phase and gas phase properties. By using multiple vibration modes (at least two different vibration modes are measured), the system can independently determine liquid density, gas volume fraction, and mixture density, thereby resolving the decoupling effect caused by gas bubbles while maintaining versatility in measuring various multicomponent fluids.

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If gas bubbles are present in the flow material, then the fluid can be measured as a mixture, but larger bubbles decouple from the liquid and move independently, adversely affecting the vibrational response

Engineering Contradiction:
Improveability to measure fluid mixturesVSAvoidvibrational response accuracy
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent employs mechanical vibration at multiple modes to differentiate between liquid and gas phases. By exciting the flow tube in at least two different vibration modes and measuring the corresponding vibrational responses, the system can distinguish between coupled liquid-gas motion and independent gas bubble motion, thereby maintaining reliability in the presence of gas bubbles while preserving mixture measurement capability.

Inventive Principle:
Principle #18Mechanical vibration

3Adaptability or versatility

If the bubble size varies with fluid velocity and pressure, then the measurement conditions change dynamically, but this causes variations in the natural or resonant frequency of the flow meter

Engineering Contradiction:
Improvehandling variable flow conditionsVSAvoidfrequency measurement accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent adopts a dynamic measurement approach by continuously monitoring multiple vibration modes and using these measurements to calculate liquid density and gas volume fraction in real-time. This dynamic adaptation to changing bubble sizes and flow conditions eliminates frequency variation errors, allowing the system to handle variable flow conditions while maintaining precision through continuous multi-mode vibration measurement and calculation.

Inventive Principle:
Principle #15Dynamics

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 approach enables precise determination of fluid characteristics, including volume fractions and flow rates of individual components, by compensating for decoupling and compressibility errors, thereby improving measurement accuracy in multicomponent fluids.

Implementation Method 1

Vibrating fluid sensors, such as Coriolis mass flow meters and vibrating densitometers typically operate by detecting motion of a vibrating conduit that contains a flowing material

Methodology Applied
Scientific EffectCoriolis force: Coriolis Force

Implementation Method 2

Excitation is typically provided by an actuator, e.g., an electromechanical device, such as a voice coil-type driver, that perturbs the conduit in a periodic fashion

Methodology Applied
Scientific EffectMechanical vibration: Vibration

Implementation Method 3

a density adjustor in fluid communication with the pipeline and the first sensor assembly, configured to adjust a density of the multicomponent fluid from a first density state to at least a second density state by adjusting a pressure and/or a temperature of the multicomponent fluid

Methodology Applied
Scientific EffectPressure increase: Pressure Increase

Implementation Method 4

a density adjustor in fluid communication with the pipeline and the first sensor assembly, configured to adjust a density of the multicomponent fluid from a first density state to at least a second density state by adjusting a pressure and/or a temperature of the multicomponent fluid

Methodology Applied
Scientific EffectThermal expansion: Thermal Expansion

Data Source

PatentEP2880417B1Fluid characteristic determination of a multi-component fluid with compressible and incompressible components
Publication Date: 2023.04.12 MICRO MOTION INC
  • EP2880417B1 patent drawingFigure 1
  • EP2880417B1 patent drawingFigure 2
  • EP2880417B1 patent drawingFigure 3

AI summary

A method for determining fluid characteristics of a multicomponent fluid is provided. The method includes a step of measuring a first density, ρ1, of a multicomponent fluid comprising one or more incompressible components and one or more compressible components at a first density state. The method further includes a step of adjusting the multicomponent fluid from the first density state to a second density state. A second density, ρ2, of the multicomponent fluid is then measured at the second density state and one or more fluid characteristics of at least one of the compressible components or the incompressible components are determined.