Pressure Sensor Cluster for Aircraft Fuel Density Measurement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Accurately gauging fuel density and volume in aircraft fuel tanks is challenging due to changes in orientation and temperature variations, leading to inefficiencies in conventional methods that require multiple sensors and lengthy installation times.

Innovation Solution

A method using clusters of pressure sensors installed in a single package, allowing for simultaneous installation and reducing installation time, which determine fluid density by combining pressure measurements from multiple sensors to calculate density and volume without the need for separate densitometers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If multiple individual pressure sensors are installed to accurately gauge fluid density, then measurement precision is improved, but installation time increases and device complexity increases

Engineering Contradiction:
Improvefluid density measurement accuracyVSAvoidinstallation time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

Multiple pressure sensors are integrated into a single sensor assembly that functions as one installable unit. This merging of multiple sensors into one compact assembly allows simultaneous installation of all sensors required for density measurement, dramatically reducing installation time while maintaining the capability to measure density accurately through combined pressure readings from multiple sensors within the assembly.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The pressure sensors are pre-positioned and calibrated within the sensor assembly before installation in the tank. This preliminary arrangement of sensors at specific locations and orientations ensures that once installed, the system can immediately begin accurate density measurements without requiring additional adjustment time, thus reducing total installation time while preserving measurement precision.

Inventive Principle:
Principle #10Preliminary action

2Measurement precision

If multiple individual pressure sensors are installed to accurately gauge fluid density, then measurement precision is improved, but device complexity increases

Engineering Contradiction:
Improvefluid density measurement accuracyVSAvoidnumber of sensors and installation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

Multiple pressure sensors are integrated into a single sensor assembly that functions as one installable unit. This merging of multiple sensors into one compact assembly simplifies the overall system by reducing the number of separate components that need to be handled, wired, and installed individually, thereby reducing device complexity while maintaining the capability to measure density accurately through combined pressure readings.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The sensor assembly serves multiple functions simultaneously: it houses multiple pressure sensors for density measurement, provides structural support for all sensors, enables centralized wiring and power supply, and facilitates single-unit installation and maintenance. This multi-functionality reduces device complexity by consolidating what would otherwise require multiple separate components and installation procedures.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Measurement precision

If dedicated densitometers are used to measure fuel density, then measurement precision is improved, but device complexity and cost increase

Engineering Contradiction:
Improvefuel density measurement accuracyVSAvoidsystem complexity and component count
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The pressure sensor assembly performs multiple functions: it measures pressure at multiple locations for density calculation, provides structural support, enables fluid level monitoring, and serves as a mounting structure for additional sensors. This multi-functionality eliminates the need for dedicated densitometers while maintaining density measurement capability, thereby reducing device complexity and component count.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The invention replaces dedicated mechanical densitometers with a pressure-based measurement system. By using pressure sensors and applying hydrostatic pressure principles, the system calculates density through pressure differential measurements rather than using specialized densitometer devices, thereby reducing device complexity while maintaining measurement precision.

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

4Ease of operation

If capacitive type sensing probes are used to gauge fluid amount, then ease of operation is improved, but measurement precision deteriorates when fluid reaches the top of the probe

Engineering Contradiction:
Improveprobe installation and operationVSAvoidfluid level measurement accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The system transitions from one-dimensional capacitive probe measurement (single point) to three-dimensional pressure field measurement using multiple pressure sensors distributed throughout the tank. This dimensional expansion allows continuous density and level measurement throughout the entire tank volume, eliminating the limitation where capacitive probes become inactive when fluid reaches the top, while maintaining ease of operation through centralized data processing.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 enhances measurement accuracy and reduces installation time by allowing for more precise fluid density determination and distribution analysis, minimizing the number of components needed and avoiding the use of expensive densitometers.

Implementation Method 1

obtaining a first pressure measurement at a first location within the tank using a first cluster of sensors; obtaining a second pressure measurement at a second location within the tank using a second cluster of sensors

Methodology Applied
Scientific EffectPressure measurement:

Data Source

PatentEP3330681B1Determining fluid density within a tank
Publication Date: 2023.07.05 SIMMONDS PRECISION PRODUCTS INC
  • EP3330681B1 patent drawingFigure 1~2
  • EP3330681B1 patent drawingFigure 3~4
  • EP3330681B1 patent drawing

AI summary

Method for determining the density of a fluid within a tank (10), e.g. aircraft fuel-tank, comprising the steps of installing two pressure sensors (12, 14) simultaneously on a common frame at a first location within the tank, of obtaining a first pressure measurement of the fluid within the tank using a pressure sensor and of determining the density of the fluid using said first pressure measurement.