Aircraft APU Fuel Conditioning With Sensor-Based Hydrogen Pressure Control
Solution Overview
Problem
The challenge of implementing hydrogen tanks in aircraft engines is to ensure sufficient fuel supply while maintaining optimal parameters and reducing weight, ensuring engines meet flight requirements, particularly for auxiliary power units that need to start quickly and provide power to essential aircraft equipment.
Innovation Solution
A conditioning system for aircraft engines that includes a fuel tank, pressure regulating means, temperature and pressure sensors, and controlling means to monitor and adjust fuel pressure and injection position, ensuring efficient fuel delivery to the engine, even when pressure is low, by adjusting injection points and using residual fuel to generate additional power in emergency situations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If hydrogen tanks are installed in aircraft to supply sufficient fuel to the engine, then the energy supply is improved, but the aircraft weight increases
Solution Approach 1:
The system dynamically adjusts fuel injection parameters (pressure, timing, position) based on real-time sensor data to optimize hydrogen combustion efficiency. By changing operational parameters rather than increasing fuel quantity, the system maintains energy supply while avoiding additional weight from larger fuel tanks
Solution Approach 2:
The APU system is designed to automatically monitor and adjust its own fuel consumption through integrated sensors and control mechanisms. This self-regulating capability ensures efficient hydrogen usage, maximizing energy extraction from the given fuel quantity without requiring weight-added backup systems
2Reliability
If the APU is designed to start quickly and supply power to essential equipment, then the reliability is improved, but the device complexity increases
Solution Approach 1:
The system performs preliminary checks and preparations before APU startup, including pre-pressurization of fuel lines and pre-heating of combustion chambers. This advance preparation ensures rapid, reliable startup while organizing complex functions into a systematic sequence that manages overall system complexity
Solution Approach 2:
The APU system is designed with multi-functional components that serve multiple purposes. For example, the fuel injection system not only delivers fuel but also helps cool engine components, and sensors monitor both combustion efficiency and mechanical health. This consolidation reduces the number of separate systems needed, managing complexity while maintaining reliability
3Manufacturing precision
If pressure regulating means and controlling means are added to optimize fuel injection, then the manufacturing precision is improved, but the device complexity increases
Solution Approach 1:
The system incorporates sensors that continuously monitor fuel pressure, temperature, and injection timing, feeding this data back to the control unit. The controller automatically adjusts injection parameters based on this feedback, achieving high precision without requiring overly complex mechanical injection mechanisms. This electronic feedback loop replaces mechanical complexity with controllable precision
Solution Approach 2:
The system replaces complex mechanical fuel injection regulation mechanisms with electronic control and sensing. Instead of using intricate mechanical linkages and adjustable components to achieve precise injection, the patent uses electronically controlled valves and actuators guided by sensor data, reducing mechanical complexity while maintaining or improving precision
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
The system maintains engine efficiency and provides additional power by optimizing fuel injection, allowing the engine to operate effectively during normal and emergency conditions, reducing the risk of inefficiencies and damage.
Implementation Method 1
a fuel tank (6) comprising an outlet connected to the fuel inlet (1) of the Auxiliary Power Unit, the fuel tank (6) being configured to maintain the pressurized gas fuel pressurized at pressure Pf
Implementation Method 2
pressure regulating means located downstream of the fuel tank, the pressure regulating means being configured to regulate the pressure of the pressurized gas fuel injected to the fuel inlet (1) of the Auxiliary Power Unit
Implementation Method 3
a first temperature sensor located downstream of the pressure regulating means and a second temperature sensor located upstream of the engine
Implementation Method 4
a first pressure sensor located inside the fuel tank, a second pressure sensor located downstream of the pressure regulating means and a third pressure sensor located at the inlet of the engine
Implementation Method 5
controlling means connected to the first, second and third pressure sensors, and to the first and second temperature sensors, the controlling means being configured for receiving temperature and pressure values from the first, second and third pressure sensors and from the first and second temperature sensors and for actuating on the pressure regulating means and/or the injection position
Implementation Method 6
an engine (4) comprising an inlet connected to the fuel conduit (3), an outlet connected to an APU outlet (5), the APU outlet (5) being configured to exhaust gases out of the engine (4), a plurality of injectors and a plurality of combustion chambers
Data Source
AI summary
An aircraft conditioning system including a fuel tank, including an outlet connected to an Auxiliary Power Unit (APU) fuel inlet, configured to maintain a pressurized gas fuel, a pressure regulator, downstream of the fuel tank, configured to regulate a pressure of the pressurized gas fuel injected to the APU inlet, a first temperature sensor downstream of the pressure regulator and a second temperature sensor upstream of an engine, a first pressure sensor inside the fuel tank, a second pressure sensor downstream of the pressure regulator and a third pressure sensor at an engine inlet, and a controller connected to the pressure sensors and the temperature sensors, the controller receiving temperature and pressure values from the pressure sensors and from the temperature sensors and actuating on at least one of the pressure regulator or the injection position of the pressurized gas fuel inside a plurality of engine combustion chambers.