After-Fan Motor-Generator Coupling for Multi-Mode Turbine Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional gas turbine engines are designed for peak efficiency during takeoff or top of climb conditions, resulting in lower efficiencies during cruise modes due to suboptimal turbine inlet temperatures.
Innovation Solution
The integration of an after-fan system with an electrical motor that includes an after-fan turbine and an electric motor coupled to the fan, allowing for adjustable energy extraction and distribution through a gear assembly or directly, enabling optimized energy use across different operational modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the gas turbine engine is designed for peak efficiency during takeoff or top of climb conditions, then maximum thrust output and operational efficiency are improved, but the engine operates at lower efficiencies during cruise modes due to suboptimal turbine inlet temperatures
Solution Approach 1:
The patent applies dynamics by making the energy extraction from the turbine dynamic and adjustable through an electrical motor coupled to the fan. The motor can vary the amount of energy extracted from the turbine based on flight conditions, allowing the engine to adapt between takeoff/climb modes (requiring maximum thrust) and cruise modes (benefiting from optimized energy distribution). This dynamic adjustment resolves the contradiction by enabling peak efficiency during takeoff while also achieving optimized efficiency during cruise.
Solution Approach 2:
The patent changes the parameter of energy extraction from the turbine by introducing an electrical motor that can selectively extract and distribute energy. During takeoff/climb, the motor can be configured to extract minimal energy to maintain maximum thrust output. During cruise, the motor extracts and redistributes energy to optimize turbine inlet temperatures and improve overall efficiency. This parameter change enables the engine to operate efficiently across different flight modes.
2Power
If maximum energy is extracted from the turbine during takeoff and climb, then thrust output is maximized, but energy availability for other components and optimized distribution during cruise is reduced
Solution Approach 1:
The patent segments the energy extraction function by introducing a separate electrical motor that is coupled to the fan through a gear assembly. This segmentation allows the turbine to focus on generating maximum power for thrust during takeoff and climb, while the electrical motor independently handles energy extraction and distribution for fan drive during cruise. This separation resolves the contradiction by enabling maximum thrust output when needed while providing flexible energy distribution during other flight modes.
Solution Approach 2:
The electrical motor acts as an intermediary between the turbine and the fan, mediating the energy transfer. During takeoff and climb, the motor can be configured to minimize energy extraction, allowing maximum turbine power to be available for thrust. During cruise, the motor intermediates by extracting and redistributing energy to optimize fan drive efficiency. This intermediary role resolves the contradiction between maximizing thrust power and optimizing energy distribution flexibility.
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 operational efficiency across various flight conditions by adjusting energy extraction and distribution, improving fuel efficiency and reducing fuel consumption during cruise modes while maintaining peak performance during takeoff and climb.
Implementation Method 1
an after-fan turbine configured to extract energy from a flow exiting the fan
Implementation Method 2
an electrical generator configured to generate current in response to rotation of the after-fan turbine
Implementation Method 3
an electric motor configured to rotate the fan in response to an electrical signal provided by the controller
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
An after-fan system for an engine (20) may comprise an after-fan turbine (122) an electrical generator (150) operationally coupled to the after-fan turbine (122), and an electric motor (152) electrically coupled to the electrical generator (150). The electrical generator (150) may be configured to generate an electrical current in response to rotation of the after-fan turbine (122). The electric motor (152) may be configured to generate torque.