Aircraft Fuel Pump Segmentation for Weight Reduction

Solution Overview

Problem

Conventional fuel systems for gas turbine engines face inefficiencies and control difficulties due to the need for a main fuel pump with large capacity to accommodate varying engine operating conditions, leading to weight and energy consumption issues.

Innovation Solution

A fuel system utilizing a main pump and a servo pump, with a servo minimum pressure valve and bypass connection element, allowing fuel to bypass the servo minimum pressure valve and flow directly between the two lines based on pressure differences, enabling efficient sharing of fuel flow to actuators and nozzles, reducing the size and power requirements of the servo pump.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the main fuel pump is sized with large capacity to accommodate the entire engine operating envelope, then fuel delivery capability is improved, but pump size and power consumption increase

Engineering Contradiction:

Improvefuel delivery capabilityVSAvoidpump weight

Core Design Contradiction:

ProductivityVSWeight of moving object

Solution Approach 1:

The fuel pump system is segmented into a main fuel pump and a servo pump that work together. The main pump handles the bulk fuel delivery while the servo pump provides supplemental flow during high power transient conditions. This segmentation allows each pump to be sized for its specific function rather than requiring one oversized pump to handle all conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between main pump-only operation and combined main pump plus servo pump operation based on engine conditions. During high power transient conditions, the servo pump is activated to supplement fuel flow. This dynamic operation allows the system to maintain adequate fuel delivery capability while keeping the main pump smaller than what would be required if it had to handle all conditions alone.

Inventive Principle:

Principle #15Dynamics

2Productivity

If the main fuel pump is sized with large capacity to accommodate the entire engine operating envelope, then fuel delivery capability is improved, but power consumption increases

Engineering Contradiction:

Improvefuel delivery capabilityVSAvoidpump power consumption

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The fuel pump system is segmented into a main fuel pump and a servo pump that work together. The main pump handles the bulk fuel delivery while the servo pump provides supplemental flow during high power transient conditions. This segmentation allows each pump to be sized for its specific function rather than requiring one oversized pump to handle all conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between main pump-only operation and combined main pump plus servo pump operation based on engine conditions. During high power transient conditions, the servo pump is activated to supplement fuel flow. This dynamic operation allows the system to maintain adequate fuel delivery capability while keeping the main pump smaller than what would be required if it had to handle all conditions alone.

Inventive Principle:

Principle #15Dynamics

3Productivity

If the main fuel pump is sized with large capacity to accommodate the entire engine operating envelope, then fuel delivery capability is improved, but control difficulty increases

Engineering Contradiction:

Improvefuel delivery capabilityVSAvoidsystem control

Core Design Contradiction:

ProductivityVSEase of operation

Solution Approach 1:

The fuel pump system is segmented into a main fuel pump and a servo pump that work together. The main pump handles the bulk fuel delivery while the servo pump provides supplemental flow during high power transient conditions. This segmentation allows each pump to be sized for its specific function rather than requiring one oversized pump to handle all conditions.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system dynamically switches between main pump-only operation and combined main pump plus servo pump operation based on engine conditions. During high power transient conditions, the servo pump is activated to supplement fuel flow. This dynamic operation allows the system to maintain adequate fuel delivery capability while keeping the main pump smaller than what would be required if it had to handle all conditions alone.

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 configuration minimizes the size and power consumption of the servo pump, resulting in weight savings and reduced heat rejection, while maintaining efficient fuel delivery to actuators and nozzles across different engine operating conditions.

Implementation Method 1

allows fuel to bypass the servo minimum pressure valve and flow directly between the two lines based on pressure differences

Methodology Applied

Scientific EffectPressure difference: Pressure Gradient

Data Source

PatentEP3232036B1Dual pump fuel system with pump sharing connection

Publication Date: 2020.09.30 HAMILTON SUNDSTRAND CORP

Figure 1A
Figure 1B
Figure 2A~2B

AI summary

A fuel system for an aircraft includes a main pump (12), a servo pump (14), a servo minimum pressure valve (20), and a servo pump bypass connection element (22). The main pump (12) receives fuel from a source (32). The servo pump (14) also receives fuel from the source (32). The servo minimum pressure valve (20) receives fuel from the main pump (12) supplied through a first line (48) and the valve (20) receives fuel from the servo pump (14) supplied through a second line (46). The servo pump bypass connection element (22) connects the first line (48) and the second line (46).