Aeronautical Engine Electric Starter Cooling via Independent Fuel Pump

Solution Overview

Problem

Existing solutions for cooling aeronautical engine electric starting devices are inefficient, as they require overdimensioning of high pressure pumps to ensure sufficient coolant flow at low speeds, leading to increased mass and complexity, and divert excessive fuel flow at high speeds.

Innovation Solution

An independent electric pump is used to feed a cooling device, connected to the fuel pumping system upstream of the high pressure pump, allowing for efficient coolant flow without overdimensioning the high pressure pump, and contributing to the main fuel circuit during starting.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If the high pressure pump is overdimensioned to ensure sufficient coolant flow at low speeds, then cooling performance at low speed is improved, but device complexity and mass increase

Engineering Contradiction:

Improvecooling performanceVSAvoidpump capacity

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The patent divides the pumping function into two separate pumps: a high pressure pump for fuel delivery and a low pressure pump for cooling. This segmentation allows each pump to be optimally sized for its specific function, avoiding the need to overdimension the high pressure pump for cooling requirements.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The low pressure pump serves dual purposes: it provides cooling for the electric starting device and also contributes to fuel delivery by feeding the high pressure pump. This multi-functionality eliminates the need for separate cooling and fuel pumping systems.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Temperature

If the high pressure pump is overdimensioned to ensure sufficient coolant flow at low speeds, then cooling performance is improved, but mass increases

Engineering Contradiction:

Improvecooling performanceVSAvoidpump mass

Core Design Contradiction:

TemperatureVSWeight of moving object

Solution Approach 1:

The patent divides the pumping function into two separate pumps: a high pressure pump for fuel delivery and a low pressure pump for cooling. This segmentation allows each pump to be optimally sized for its specific function, avoiding the need to overdimension the high pressure pump for cooling requirements.

Inventive Principle:

Principle #1Segmentation

3Temperature

If additional pumps are added to feed the cooling device, then cooling performance is improved, but device complexity and mechanical links increase

Engineering Contradiction:

Improvecooling performanceVSAvoidmechanical links

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The low pressure pump serves dual purposes: it provides cooling for the electric starting device and also contributes to fuel delivery by feeding the high pressure pump. This multi-functionality eliminates the need for separate cooling and fuel pumping systems.

Inventive Principle:

Principle #6Universality (Multi-functionality)

4Temperature

If the high pressure pump capacity is increased to provide cooling flow, then cooling performance is improved, but fuel diversion to main circuit decreases

Engineering Contradiction:

Improvecooling flow rateVSAvoidfuel flow to main circuit

Core Design Contradiction:

TemperatureVSQuantity of substance

Solution Approach 1:

The patent divides the pumping function into two separate pumps: a high pressure pump for fuel delivery and a low pressure pump for cooling. This segmentation allows each pump to be optimally sized for its specific function, avoiding the need to overdimension the high pressure pump for cooling requirements.

Inventive Principle:

Principle #1Segmentation

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 solution provides sufficient cooling without increasing bulkiness or complexity, enabling efficient operation at low speeds and reducing fuel diversion at high speeds, allowing for the use of lighter and more reliable high pressure pumps.

Implementation Method 1

cooling device for the electric starting device connected to the pumping device in order to ensure cooling by circulation of fuel

Methodology Applied

Scientific EffectHeat exchange: Heat Exchanger

Data Source

PatentUS9394832B2Aeronautical engine with cooling of an electric starting device

Publication Date: 2016.07.19 SAFRAN AIRCRAFT ENGINES SAS

AI summary

An aeronautical engine including a fuel pumping device including a high pressure fuel pump including an inlet connected to a low pressure fuel conduit and an outlet connected to a main circuit for feeding high pressure fuel, an electric device starting the engine, and a device cooling the electric starting device connected to the pumping device to ensure cooling by circulation of fuel. The cooling device is supplied with fuel by a pump that includes an inlet connected to the pumping device, upstream from the high pressure pump, and that is driven by an electric motor independently of the high pressure pump.