Multiphase Flow Meter Reynolds Number Correction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing multiphase flow meters based on differential pressure devices, such as venturi tubes, struggle with accurate measurement of flow rates in multiphase fluids containing high viscosity oils due to variations in Reynolds number, emulsion type, and viscosity, leading to significant measurement errors, especially in heavy oil applications where the emulsion type changes from water continuous to oil continuous.

Innovation Solution

A method that determines the Reynolds number of the multiphase mixture using a pipe section with known wall roughness, allowing for the calculation of a correct discharge coefficient for differential pressure-based flow meters, and an emulsion classification measurement to determine oil viscosity, enabling accurate flow rate measurements despite variations in viscosity and emulsion type.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If differential pressure-based flow meters are used for multiphase flow measurement, then flow rate measurement is enabled, but measurement precision deteriorates due to Reynolds number variations and emulsion type changes

Engineering Contradiction:
Improveflow rate measurement precisionVSAvoidadaptability to viscosity and emulsion type variations
Core Design Contradiction:
Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The discharge coefficient is made dynamic by determining it based on the measured Reynolds number rather than using a fixed value. The system continuously adapts the discharge coefficient to match current flow conditions, resolving the contradiction between measurement precision and adaptability to varying viscosity and emulsion types.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The invention changes the parameter used to determine discharge coefficient from a fixed value to a variable based on Reynolds number. By measuring Reynolds number and using it to select or calculate the appropriate discharge coefficient, the system achieves both precision and adaptability across different flow conditions.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If test separators are used for well monitoring, then phase separation and measurement are achieved, but productivity deteriorates due to long stabilization time and space occupation

Engineering Contradiction:
Improvephase flow rate measurementVSAvoidwell monitoring efficiency
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The invention replaces the mechanical test separator system with a differential pressure-based flow meter that measures flow rates without requiring physical phase separation. This substitution eliminates the need for large separation tanks and long stabilization periods, thereby improving productivity while maintaining measurement capability.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The invention extracts the measurement function from the test separator system. Instead of using a complete separation system, only the essential measurement capability is retained through differential pressure sensing, removing the unnecessary bulk and time requirements of full phase separation.

Inventive Principle:
Principle #2Taking out (Extraction)

3Ease of operation

If gravity or cyclone based separators are used for phase separation, then phase separation is achieved, but measurement precision deteriorates when oil and water densities are similar and oil viscosity is high

Engineering Contradiction:
Improvephase separation capabilityVSAvoidflow rate measurement accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The invention replaces gravity and cyclone-based mechanical separation systems with a differential pressure measurement system that does not rely on density differences or viscosity characteristics. This substitution allows accurate measurement even when oil and water have similar densities or when oil viscosity is high, as the measurement is based on pressure differential rather than physical separation.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 accurate determination of Reynolds number and discharge coefficient, reducing measurement errors to ±5% or better, and allows for the identification of diluent and heavy oil components in multiphase streams, improving the reliability of flow rate measurements in heavy oil applications.

Implementation Method 1

determining a Reynolds number of the multiphase mixture by measuring a pressure drop across a pipe section of known wall roughness

Methodology Applied
Scientific EffectPressure drop: Pressure Drop

Implementation Method 2

measurement of differential pressures across a restriction in the pipe such as a Venturi tube, Orifice plate, v-Cone, Dall tube, flow mixer or Wedge tube

Methodology Applied
Scientific EffectDifferential pressure measurement: Pressure Drop

Data Source

PatentEP3052905B1A method and apparatus for measurement of individual components of a multiphase fluid
Publication Date: 2020.04.01 FMC KONGSBERG SUBSEA AS
  • EP3052905B1 patent drawingFigure 1~2
  • EP3052905B1 patent drawingFigure 3~4
  • EP3052905B1 patent drawingFigure 5~6

AI summary

A method for determining the flow rates of a multi-component mixture in a pipe including a gas phase and a liquid phase comprising an emulsion of oil and water, the emulsion being either of the water continuous type or the oil continuous type, the method comprising the following steps: a. the flow rates of the individual components of the multi-component mixture are measured, b. the Reynolds number of the multi -component mixture is measured, c. the emulsion type of the liquid phase of the multi-component mixture is determined, and d. based on the results from steps b and c, a more accurate flow-rate of the individual components of the multi-component mixture and a fluid property of at least one of the components of the multi-component mixture are calculated. An apparatus for performing the method is also disclosed.