Fuel Delivery System Contrail Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods to reduce vapour trail formation from aircraft engines, such as using ultra-low sulphur fuel, heat exchangers, electromagnetic energy, ultrasound, and chemicals, incur weight penalties, fuel-burn penalties, or increase detectability, and are not efficient in optimizing the use of expensive biofuels.
Innovation Solution
A fuel delivery system with a vapour trail detection sensor and controller that adjusts fuel composition ratios in real-time to minimize contrail optical depth, using a combination of coarse and fine search algorithms to identify optimal fuel blends, reducing soot emission index and thus the climate warming impact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If heat exchanger and condenser arrangement are used to suppress vapour trail formation, then vapour trail formation is reduced, but significant weight is introduced into the engine
Solution Approach 1:
The patent extracts only the essential function of vapour trail suppression by using fuel composition control rather than physical heat exchanger and condenser equipment. This removes the heavy mechanical infrastructure while retaining the core benefit of reduced vapour trail formation through chemical means (fuel additives that modify exhaust composition).
Solution Approach 2:
The patent replaces the mechanical system (heat exchanger and condenser) with a chemical system (fuel composition control). Instead of using physical equipment to cool and condense exhaust gases, the system uses chemically modified fuel to alter the exhaust composition and prevent vapour trail formation, thereby eliminating the weight penalty of mechanical components.
2Object-affected harmful factors
If directed electromagnetic energy is used to suppress vapour trail formation, then vapour trail formation is reduced, but weight penalty and significant fuel-burn penalty are incurred
Solution Approach 1:
The patent applies preliminary action by modifying the fuel composition before combustion occurs. Fuel additives are mixed into the fuel supply in advance, so that when the fuel is burned, the exhaust already has the desired modified composition that prevents vapour trail formation. This eliminates the need for post-combustion energy input devices like electromagnetic generators.
Solution Approach 2:
The patent replaces the electromagnetic energy system with a chemical system. Instead of using electromagnetic generators that consume significant engine power, the system uses chemically modified fuel that passively achieves vapour trail suppression through its composition, thereby eliminating the fuel-burn penalty associated with active electromagnetic systems.
3Object-affected harmful factors
If chemicals are injected into the engine or exhaust plume to modify vapour trails, then vapour trail formation is suppressed, but additional pollution and weight penalty are incurred
Solution Approach 1:
The patent merges the vapour trail suppression function with the existing fuel system. Instead of injecting separate chemical additives into the exhaust plume or engine, the suppressive chemicals are integrated into the fuel itself. This combines the propulsion function and the vapour trail suppression function into a single fuel delivery system, eliminating additional pollution from separate chemical injection systems.
Solution Approach 2:
The patent makes the fuel serve multiple functions: it provides energy for propulsion and simultaneously modifies exhaust composition to prevent vapour trail formation. The fuel additive system is designed to work within the existing fuel infrastructure, making the fuel universally responsible for both propulsion and environmental mitigation, thereby avoiding additional pollution from dedicated chemical injection systems.
4Object-affected harmful factors
If aircraft route around regions prone to vapour trail formation, then vapour trail formation is avoided, but fuel-burn penalty and increased workload are incurred
Solution Approach 1:
The patent enables the aircraft to self-regulate its exhaust composition to prevent vapour trail formation regardless of ambient conditions. The fuel system automatically adjusts the fuel composition to modify exhaust properties, making the aircraft self-sufficient in preventing vapour trails without needing to avoid specific flight regions or incur additional fuel-burn penalties from altered routing.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
This invention concerns a fuel delivery system for an engine, in which two or more discrete fuel compositions are made available to the engine. The system has a vapour trail detection sensor (20) configured to generate a detection signal indicative of a characteristic of a vapour trail. A regulator (42, 44, 46, 60) is configured to regulate a percentage of a first and a second fuel composition delivered to the engine as resultant fuel composition. A controller (40) is arranged to undertake a search of trial fuel compositions by controlling the regulator to deliver to the engine a plurality of trial fuel compositions having different ratios of the first and second fuel compositions. The controller controls delivery of a resultant fuel composition to the engine in response to the vapour trail characteristic detection signals for said plurality of trial fuel compositions.