Gaseous Fuel Pressure Regulation for In-Cylinder Engine Injection
Solution Overview
Problem
Existing technologies lack effective methods for pressure regulating and injecting gaseous fuels, particularly hydrogen and natural gas, into internal combustion engines, leading to energy penalties and decreased fuel economy due to inefficient pressurization and combustion modes.
Innovation Solution
An apparatus and method utilizing a pressure regulator, in-cylinder fuel injector, and controller to regulate and inject gaseous fuels at specific pressures and timings, with optional bypass valves and sensors to manage fuel type and hydrogen content, ensuring efficient combustion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If hydrogen is stored as compressed gas at high pressure (700 bar) to increase storage density, then the storage density and range of the fuel cell vehicle are improved, but the storage pressure must be down regulated to operating pressure (less than 5 bar) which creates energy penalties and decreases fuel economy
Solution Approach 1:
The patent changes the storage state of hydrogen from compressed gas to liquefied form, which fundamentally alters the density and compression characteristics. This allows the system to store hydrogen at high density while enabling direct injection at appropriate combustion pressures without excessive energy penalties for pressure regulation.
Solution Approach 2:
The patent utilizes the phase transition of hydrogen from liquid to gas state during combustion. By storing hydrogen in liquefied form and allowing it to vaporize in the combustion chamber, the system achieves high storage density while the phase change occurs naturally during the combustion process, reducing the energy penalty associated with pressurization.
2Productivity
If gaseous fuel is pressurized to high injection pressure (300 bar) for direct injection into combustion chamber, then the injection capability and combustion efficiency are improved, but the energy penalty for pressurization increases significantly
Solution Approach 1:
The patent changes the physical state of the fuel from gas to liquid for storage, and utilizes the phase change during combustion. This allows the system to achieve high injection pressures for efficient combustion while the liquid-to-gas phase transition occurs in the combustion chamber, reducing the energy required for pressurization compared to compressing gas directly.
Solution Approach 2:
The patent performs the pressurization action during the combustion process itself rather than before injection. By introducing the fuel in a state that requires minimal pressurization and allowing the combustion chamber conditions to facilitate the necessary pressure increase, the system reduces the energy penalty associated with pre-pressurization.
3Stress or pressure
If hydrogen is stored as liquefied form at cryogenic temperatures to reduce storage pressure, then the storage pressure is reduced from 700 bar, but the storage density decreases compared to compressed gas storage
Solution Approach 1:
The patent changes the storage parameters of hydrogen by utilizing cryogenic temperatures to achieve liquefaction. This phase change enables storage at much lower pressures (compared to 700 bar compressed gas) while maintaining high storage density through the liquid state, which is approximately an order of magnitude denser than gaseous hydrogen at standard 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
Enhances fuel economy by optimizing injection pressures and combustion modes, reducing energy penalties, and enabling efficient operation of gaseous fuel engines.
Implementation Method 1
a pressure regulator and an in-cylinder fuel injector. The pressure regulator regulates a pressure of the gaseous fuel
Implementation Method 2
the in-cylinder fuel injector directly injects the gaseous fuel into a combustion chamber of the internal combustion engine
Implementation Method 3
gaseous fuel is injected directly into the combustion chamber near the latter part of a compression stroke
Data Source
AI summary
An apparatus includes a pressure regulator, an in-cylinder fuel injector and a controller programmed to, when fueling with a first gaseous fuel, command the regulator to regulate the pressure of the first gaseous fuel to a first injection pressure; and command the injector to inject within 90 CA° of TDC during a compression stroke an injected quantity of a first gaseous fuel into the combustion chamber at the first injection pressure, and when fueling with a second gaseous fuel, to command the regulator to regulate the pressure of the second gaseous fuel to a second injection pressure; and command the injector to inject within 90 CA° of TDC during the compression stroke an injected quantity of a second injected gaseous fuel.