Gas Turbine Fuel Manifold Purging via Pump
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Gas turbine engines in twin-engine helicopters operate inefficiently during cruise conditions due to the need for both engines to run at all times, limiting fuel efficiency gains and requiring significant power from one engine to compensate for the other in case of a failure, while also facing maintenance and reliability challenges.
Innovation Solution
Implementing an asymmetric operating mode where one engine operates at high power and the other at low or zero power, with a fuel system that includes a flow divider valve to manage fuel flow and prevent coking, allowing for rapid power increase in emergencies and reducing fuel consumption during idle periods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If both engines operate at all times during flight, then safety and reliability are improved, but fuel efficiency deteriorates
Solution Approach 1:
The fuel supply system is segmented into multiple fuel manifolds (first fuel manifold and second fuel manifold) that can be independently controlled. This allows selective fuel delivery to different engines or fuel manifolds, enabling one engine to be operated at low power or shut down while maintaining the other, thus improving fuel efficiency while preserving the ability to maintain reliability when needed
Solution Approach 2:
The system dynamically switches between different fuel manifold configurations based on operational requirements. During normal operation, both fuel manifolds can be active; during cruise, one can be deactivated; and during emergencies, the system can rapidly transition to full power on one engine. This dynamic adaptability resolves the contradiction between maintaining constant reliability and achieving fuel efficiency
2Use of energy by moving object
If one engine is shut down during cruise, then fuel efficiency is improved, but the ability to rapidly compensate for power loss deteriorates
Solution Approach 1:
The fuel system maintains pre-configured fuel delivery pathways and pressure systems in both fuel manifolds even when one is not actively delivering fuel. The fuel pump and control systems remain ready, and fuel lines are pre-charged, allowing immediate activation of the standby fuel manifold when power compensation is needed, thus enabling rapid response without sacrificing fuel efficiency during normal cruise
Solution Approach 2:
The fuel manifold system acts as an intermediary between the fuel source and the engines, providing a buffer that can rapidly redirect fuel flow. When one engine needs to increase power, the fuel manifold system can quickly transition fuel delivery from the currently active manifold to the standby manifold or increase flow to the active manifold, enabling rapid power response while maintaining fuel efficiency during idle periods
3Use of energy by moving object
If fuel flow is stopped to one fuel manifold, then fuel consumption is reduced, but fuel line coking and maintenance needs increase
Solution Approach 1:
The system maintains continuous, low-level fuel flow or periodic purging action through the fuel manifold that would otherwise be idle. This continuous or periodic action prevents fuel stagnation and coking in the fuel lines and manifold, reducing maintenance requirements while still achieving significant fuel consumption reduction compared to keeping both engines at full operational fuel flow
Solution Approach 2:
The system uses pneumatic or hydraulic means (such as introducing compressed air or inert gas) to purge residual fuel from the inactive fuel manifold and lines. This purging action prevents coking and maintains the fuel delivery system in good condition, reducing maintenance needs while allowing the system to operate with reduced fuel consumption during cruise conditions
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 enhances fuel efficiency, reduces maintenance needs, and enables quicker power recovery in emergencies by allowing one engine to rapidly increase output while minimizing fuel consumption during idle periods.
Implementation Method 1
A pump is provided in the fuel system to pressurize the fuel
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of operating a gas turbine engine (10B) in a low-power condition includes supplying fuel to a combustor (16B) by supplying fuel to a first fuel manifold (62A) and a second fuel manifold (62B) of the gas turbine engine (10B). The method also includes, while supplying fuel to the combustor (16B) by supplying fuel to the first fuel manifold (62A): stopping supplying fuel to the second fuel manifold (62B); and using a pump to drive gas into the second fuel manifold (62B) to flush fuel in the second fuel manifold (62B) into the combustor (16B) and hinder coking in the second fuel manifold (62B) and associated fuel nozzles (61B).