Gas Turbine Fuel Specific Gravity Estimation
Solution Overview
Problem
Existing gas turbine engine control systems face challenges in accurately and efficiently determining the specific gravity of fuel in real-time, especially when fuel composition changes, which affects safe and reliable operation.
Innovation Solution
A method and system for estimating the specific gravity of fuel in gas turbine engines using measurements from mass flow meters, pressure sensors, and temperature sensors, combined with a recursive filtering process to provide a reliable and accurate estimate of fuel specific gravity, enabling effective control and monitoring.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional methods are used to determine fuel specific gravity, then measurement accuracy can be maintained, but the system complexity and cost increase significantly
Solution Approach 1:
The patent replaces complex mechanical measurement systems with a computational approach that uses existing sensor data (mass flow, pressure, temperature) and recursive filtering algorithms to calculate specific gravity, eliminating the need for specialized mechanical measurement equipment
Solution Approach 2:
The patent introduces a recursive filter as an intermediary processing layer that combines multiple measurement signals (mass flow, pressure, temperature) to produce a refined specific gravity estimate, mediating between raw sensor data and final measurement output
2Reliability
If real-time specific gravity determination is implemented, then fuel composition changes can be detected promptly, but computational processing time increases
Solution Approach 1:
The patent implements continuous real-time calculation of specific gravity using recursive filtering that operates continuously as fuel flows through the system, maintaining uninterrupted detection capability without periodic interruptions
Solution Approach 2:
The patent uses recursive filtering that incorporates feedback from previous measurements and calculations to refine current specific gravity estimates, allowing the system to learn from historical data and improve accuracy over time while reducing computational burden
3Measurement precision
If multiple measurement points are used to improve accuracy, then specific gravity estimation reliability increases, but the number of required sensors and measurement locations increases
Solution Approach 1:
The patent makes existing sensors (mass flow meter, pressure sensors, temperature sensors) multi-functional by using them not only for their primary functions but also for calculating specific gravity, eliminating the need for dedicated specific gravity sensors
Solution Approach 2:
The patent merges multiple measurement functions into a single integrated calculation system that combines mass flow, pressure, and temperature data to derive specific gravity, consolidating what would traditionally require separate measurement systems
Data Source
AI summary
A method for determining an estimate of the specific gravity of a fuel for a gas turbine engine is disclosed. The gas turbine engine includes a fuel control valve and one or more fuel injectors. The method includes determining a first estimate of the specific gravity based on an orifice flow model of the fuel control valve. The method also includes determining a second estimate of the specific gravity based on a combined orifice flow model of the one or more fuel injectors. The method further includes recursively filtering the first estimate and the second estimate to determine a third estimate of the specific gravity.