Gas Turbine Light-Off Detection via Acceleration Rate Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for detecting engine light-off in gas turbine engines, such as measuring temperature rises, are not always reliable and can be complex, lacking precision and accuracy, especially in varying flight conditions.
Innovation Solution
A system and method that utilize a comparison module to determine engine light-off by analyzing the rate of change in acceleration of the gas turbine engine components, using lookup tables for predetermined thresholds based on altitude, velocity, and other flight conditions, allowing for adjustments in fuel flow and ignition signals to confirm the event.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If temperature measurement methods are used to detect engine light-off, then detection capability is provided, but reliability and precision are insufficient especially in varying flight conditions
Solution Approach 1:
The patent changes the detection parameter from temperature (which has reliability and precision issues in varying flight conditions) to acceleration rate (which provides consistent and reliable detection across all flight conditions). The controller monitors the acceleration rate of the engine and compares it against predetermined thresholds to detect light-off events, eliminating the problems associated with temperature-based detection.
2Measurement precision
If temperature probes and complex measurement systems are used, then detection capability is improved, but system complexity increases
Solution Approach 1:
The patent extracts the essential detection function from complex temperature measurement systems and probes, implementing light-off detection through acceleration rate monitoring alone. This extraction eliminates the need for temperature probes and complex measurement infrastructure while maintaining or improving detection accuracy through a simpler system architecture.
Solution Approach 2:
The patent replaces the thermal measurement system (temperature probes and thermal sensors) with a mechanical/electrical measurement system that monitors acceleration rate. This substitution uses the existing acceleration sensing capability of the engine control system rather than adding separate temperature measurement hardware, thereby reducing system complexity.
3Productivity
If conventional detection methods are used, then basic detection is achieved, but startup efficiency and propulsive performance are reduced
Solution Approach 1:
The patent implements a feedback mechanism where the controller continuously monitors acceleration rate and compares it against predetermined thresholds to detect light-off events. This feedback loop enables real-time detection and immediate response, allowing the system to optimize fuel injection timing and other operational parameters to improve startup efficiency and maintain propulsive performance.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A fuel assembly (160) for a gas turbine engine (10; 20) includes a fuel valve (162) that meters flow of fluid between a combustor (56) and a fuel supply (FS), and a controller (172) in communication with the fuel assembly (160). The controller (172) is programmed to receive data corresponding to a present rotational speed of a gas turbine engine component (172) and data corresponding to at least one present flight condition, and is programmed to cause a flow rate from the fuel valve (162) to change in response to determining that a rate of change in an acceleration rate relating to the present rotational speed meets at least one predetermined threshold. At least one predetermined threshold relates to an engine light-off event of the combustor (56) and is based upon the at least one present flight condition.