Aircraft Propulsion With Intermittent Combustion for Fuel Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing propulsion systems for business jets are not cost-effective and fuel-efficient, particularly at high altitudes and fast speeds, necessitating improvements in engine power and efficiency.
Innovation Solution
The use of an intermittent combustion engine, configured as a turbo-compounded or turbocharged engine, is integrated within the aircraft fuselage, with propulsors located externally and connected via a drivetrain system, including a powerplant transmission and compliant couplings, to optimize power distribution and reduce drag.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If small gas turbine engines are used for generating aircraft propulsion, then the aircraft can fly at high altitudes and fast speeds, but the propulsion system is not cost-effective and fuel-efficient
Solution Approach 1:
The patent employs intermittent combustion engines that operate in periodic cycles rather than continuous combustion. The engine performs a power stroke followed by a coasting phase, creating periodic action that improves fuel efficiency while maintaining necessary power output for high-altitude and fast-speed flight
Solution Approach 2:
The patent changes the operational parameters of the combustion engine by using intermittent combustion cycles with variable compression ratios and adjustable valve timing. This allows the engine to optimize fuel-air mixture combustion efficiency across different flight conditions, reducing energy loss while maintaining power requirements
2Object-affected harmful factors
If the engine is integrated within the aircraft fuselage with external propulsors, then drag is reduced, but the drivetrain system becomes more complex
Solution Approach 1:
The patent segments the propulsion system into distinct components: the combustion engine integrated within the fuselage, external propulsors mounted on the aircraft, and a drivetrain system connecting them. This segmentation allows the engine to be positioned optimally for drag reduction while propulsors are placed on aerodynamic surfaces, with the drivetrain managing the mechanical connection
3Loss of energy
If turbo-compounding or turbocharging is applied to the intermittent combustion engine, then engine efficiency is enhanced, but the device complexity increases
Solution Approach 1:
The patent merges the turbocharger or compounding system with the intermittent combustion engine by integrating the turbine into the existing combustion cycle. The exhaust gases from the intermittent combustion directly drive the turbocharger compressor or compounding turbine, combining waste energy recovery with the primary propulsion function in a unified 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 configuration enhances engine efficiency and reduces drag, providing cost-effective and fuel-efficient propulsion suitable for high-altitude and fast-speed flight.
Implementation Method 1
an intermittent combustion engine, configured as a turbo-compounded or turbocharged engine
Implementation Method 2
configured as a turbo-compounded or turbocharged engine
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An aircraft system (20) includes a first propulsor (36A), a second propulsor (36B), a drivetrain and an intermittent combustion engine (66). The first propulsor (36A) includes a first propulsor rotor (42A) and a first vane array (44A). The second propulsor (36B) includes a second propulsor rotor (42B) and a second vane array (44). The drivetrain includes a drive structure (100) and a transmission (106). An output (118) of the transmission (106) is coupled to the first propulsor rotor (42A) and the second propulsor rotor (42B) through the drive structure (100). The intermittent combustion engine (66) is configured to drive rotation of the first propulsor rotor (42A) and the second propulsor rotor (42B) through the drivetrain.