Fuel Valve with Ignition Liquid Push Mechanism for Gaseous Fuel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Large low-speed uniflow turbocharged two-stroke internal combustion engines face challenges in reliably self-igniting gaseous fuels due to the difficulty in accurately dosing small amounts of pilot ignition liquid, leading to increased emissions and complexity with existing dual fuel systems.
Innovation Solution
A fuel valve design featuring an elongated housing with a nozzle and axially displaceable valve needle, where ignition liquid is slowly delivered to a fuel chamber and pushed ahead of high-pressure gaseous fuel into the nozzle, combining with hot compressed air for controlled ignition within the nozzle.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a full size fuel injection system is used to deliver pilot oil, then the system can handle full load operation, but the dosage precision for small pilot amounts deteriorates
Solution Approach 1:
The fuel injection system is segmented into two separate valves: a main fuel injection valve for full load operation and a pilot fuel injection valve for precise pilot oil dosing. This segmentation allows each valve to be optimized for its specific function, resolving the contradiction between handling full load volumes and achieving precise small dosages.
Solution Approach 2:
The main fuel injection valve is designed to serve dual purposes: it handles both full load fuel injection and pilot oil injection when used in conjunction with the pilot valve. This multi-functionality reduces the need for completely separate systems while maintaining dosage precision through the dedicated pilot valve.
2Measurement precision
If additional small pilot oil injection valves are added, then dosage precision improves, but device complexity increases
Solution Approach 1:
The pilot fuel injection valve and main fuel injection valve are merged into a coordinated dual-valve system that shares common fuel supply lines and control electronics. This merging approach achieves precise pilot dosing without the complexity of entirely separate injection systems, as the valves work together within a unified architecture.
3Reliability
If three gaseous fuel valves and three fuel oil valves are installed per cylinder, then reliable ignition is ensured, but the top cover becomes crowded
Solution Approach 1:
The pilot oil injection function is extracted from the main fuel injection valve and assigned to a dedicated pilot fuel injection valve. This extraction allows for optimized positioning of the pilot valve closer to the gaseous fuel injection point, ensuring reliable ignition while maintaining a more organized and less crowded top cover layout through functional specialization.
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 solution enables reliable self-ignition of gaseous fuels without additional ignition equipment, reducing emissions and simplifying the engine design by accurately controlling the small amount of ignition liquid, thus improving engine reliability and efficiency.
Implementation Method 1
The second high pressure is higher than the first high pressure... the accumulated ignition liquid is pushed ahead of the gaseous fuel and thereby the ignition liquid enters the hollow injection nozzle just before the gaseous fuel
Implementation Method 2
supply pressurized gaseous fuel at a first high pressure to a fuel valve... The gaseous fuel then flows towards the hollow interior of the nozzle, i.e. into the sac volume
Implementation Method 3
The gaseous fuel then ignites inside the hollow nozzle with the help of the ignition liquid... Transform Chemical Energy to Thermal Energy
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
A fuel valve (50) for injecting gaseous fuel into the combustion chamber of a self-igniting internal combustion engine. The fuel valve (50) comprises an elongated fuel valve housing (52) with a rear end and a front end, a nozzle (54) with a plurality of nozzle holes (56) opening to a sac volume (55) inside the nozzle (54), the nozzle (54) being disposed at the front end of the elongated valve housing (52), a gaseous fuel inlet port (53) in the elongated fuel valve housing (52) for connection to a source (60) of high pressure gaseous fuel, an axially displaceable valve needle (61) slidably received in a longitudinal bore (77) in the elongated valve housing (52), the axially displaceable valve needle (61) having a closed position and an open position, the axially displaceable valve needle (61) rests on a valve seat (69) in the closed position and the axially displaceable valve needle (61) has lift from the valve seat (69) in the open position, the valve seat (69) being placed between a fuel chamber (58) and an outlet port (68), the fuel chamber (58) is fluidly connected to the gaseous fuel inlet port (53), the outlet port (58) is fluidly connected to the sac volume (55) in the nozzle (54), an actuator system for controllably moving the axially displaceable valve needle (61) between the closed position and the open position, an ignition liquid inlet port (78,98) for connection to a source of high pressure ignition liquid (57), and an ignition liquid supply conduit (76,99) connecting the ignition liquid inlet port (78,98) to the fuel chamber (58), the ignition liquid supply conduit (76,99) including a fixed flow restriction.