Aircraft Environmental Control Mixing Bleed and Ram Air

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Solution Overview

Problem

Current air conditioning systems in aircraft face inefficiencies in fuel burn and require significant bleed air, which can be reduced by utilizing electrical power and lower engine pressures to improve airplane efficiency.

Innovation Solution

An environmental control system that mixes mediums from different sources, such as bleed air and fresh air, to power the system and provide cabin pressurization and cooling, using a compressing device with components like air cycle machines, heat exchangers, and valves to optimize energy use and reduce fuel burn, with varying mixing points based on altitude operations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If bleed air is used to power the air conditioning system, then the system can operate with mechanical compression, but fuel burn efficiency decreases and engine efficiency is reduced

Engineering Contradiction:
Improvefuel burn efficiencyVSAvoidbleed air usage
Core Design Contradiction:
Use of energy by moving objectVSLoss of energy

Solution Approach 1:

The patent combines electric compression with heat exchanger cooling to create a hybrid air conditioning system. The compressor uses electrical power instead of bleed air to compress outside air, while heat exchangers provide cooling. This merging of electric and thermal systems reduces dependency on bleed air and improves fuel burn efficiency.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent replaces the traditional mechanical bleed air-powered compression system with an electrically-driven compression system. The compressor is powered by electrical power from the aircraft's electrical system rather than by bleed air from the engines, substituting mechanical energy with electrical energy to improve overall system efficiency.

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

2Power

If higher engine pressure is used to provide bleed air, then more compression power is available, but engine efficiency decreases

Engineering Contradiction:
Improvecompression powerVSAvoidengine efficiency
Core Design Contradiction:
PowerVSUse of energy by moving object

Solution Approach 1:

The patent substitutes electrical power for mechanical bleed air power. Instead of using high-pressure bleed air from the engines to drive the compression, an electric motor drives the compressor. This reduces the demand for high engine pressure and allows the engines to operate at more efficient pressure levels.

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

Solution Approach 2:

The patent changes the energy source parameter from mechanical (bleed air) to electrical. This parameter change allows the system to obtain compression power without requiring high engine pressure, thereby improving engine efficiency while maintaining adequate compression power through electrical drive.

Inventive Principle:
Principle #35Parameter changes

3Use of energy by moving object

If bleed air is eliminated entirely, then fuel burn efficiency improves, but the system loses the ability to compress and cool air using thermal energy

Engineering Contradiction:
Improvefuel burn efficiencyVSAvoidenergy source flexibility
Core Design Contradiction:
Use of energy by moving objectVSAdaptability or versatility

Solution Approach 1:

The patent creates a multi-functional air conditioning system that can operate using multiple energy sources. The system can use electrical power for compression and thermal energy from heat exchangers for cooling, providing versatility in energy utilization while maintaining improved fuel burn efficiency compared to traditional bleed air systems.

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

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 achieves high fuel burn efficiency by reducing bleed air usage by 40% to 75%, enhancing engine efficiency and passenger comfort, while maintaining or improving air quality and cabin conditions.

Implementation Method 1

a compressing device to compress outside air

Methodology Applied
Scientific EffectCompression: Compression

Implementation Method 2

heat exchangers

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Data Source

PatentEP3248877B1Mixing bleed and ram air at a turbine inlet
Publication Date: 2023.05.10 HAMILTON SUNDSTRAND CORP
  • EP3248877B1 patent drawingFigure 1
  • EP3248877B1 patent drawingFigure 2A
  • EP3248877B1 patent drawingFigure 2B

AI summary

An airplane is provided. The airplane includes a first medium, a second medium, and an air conditioning. The air conditioning system includes a first turbine (213), a compressor (212), and a mixing point (M1). The compressor (212)is located upstream of the turbine (213) in a flow path of the first medium. The mixing point is a location at which the first medium mixes with the second medium. The mixing point (M1) is downstream of the compressor (212) and upstream of the turbine (213).