Wall Integrated Fluid Injection for IC Engine Combustion
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Solution Overview
Problem
Conventional internal combustion engine fuel injectors have a limited surface area, leading to inefficient fuel distribution, incomplete combustion, poor emissions, and increased side reactions due to the discharge of fuel from a single point, resulting in issues like long fuel jets, wall wetting, and excessive liquid lengths.
Innovation Solution
The implementation of a Wall Integrated Fluid Injection system with multiple, evenly spaced injection sites around the combustion chamber, utilizing micro nozzles for intense mixing and reducing orifice diameters to enhance mass transfer and create multiple localized combustion zones, allowing for instantaneous fluid transfer and improved fuel and oxidant mixing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of moving object
If fuel is discharged from a single injector tip, then the injection process can be completed within a few crank angle degrees, but this results in long fuel jets, excessive liquid lengths, poor droplet distribution, and wall wetting
Solution Approach 1:
The single injector tip is segmented into multiple injectors distributed around the combustion chamber periphery. Each injector has multiple spray holes, creating numerous small injection zones instead of one large injection zone. This segmentation reduces fuel jet length and prevents wall wetting while maintaining complete injection within a few crank angle degrees.
Solution Approach 2:
The injection system transitions from a single-point (0D) or localized (1D) injection at the tip to a distributed peripheral arrangement (2D/3D) around the combustion chamber. This dimensional change allows fuel to be injected at multiple locations simultaneously, reducing the path length to the combustion zone and eliminating wall wetting issues.
2Quantity of substance
If the injector tip size is increased to discharge more fuel, then the fuel distribution improves, but the surface to volume ratio decreases and incomplete combustion occurs
Solution Approach 1:
Instead of one large injector tip, the system uses multiple smaller injectors distributed peripherally. Each injector handles a portion of the total fuel quantity, maintaining a high surface-to-volume ratio across all injectors collectively. This ensures complete combustion while achieving the required total fuel discharge volume.
Solution Approach 2:
Each injector is positioned at a specific location around the combustion chamber periphery, creating localized injection zones. This local quality approach ensures that each region receives appropriate fuel quantity with optimal surface-to-volume ratio, preventing incomplete combustion while meeting overall fuel delivery requirements.
3Object-affected harmful factors
If conventional batch type combustion is used, then combustion temperature can be kept below Nox formation threshold, but engine efficiency is reduced
Solution Approach 1:
The batch combustion process is segmented into multiple localized combustion zones distributed around the combustion chamber. Each zone operates as a mini-combustion region with controlled temperature and stoichiometry. This allows efficient combustion in each zone while distributing heat release, preventing excessive peak temperatures that cause Nox formation.
Solution Approach 2:
The system changes combustion parameters by creating multiple localized zones with different fuel-air ratios and temperature profiles. Each zone can be optimized for efficient combustion while the distributed arrangement prevents runaway temperature increases, enabling high efficiency operation without exceeding Nox formation thresholds.
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 approach enables efficient mixing and combustion, reducing emissions, eliminating the need for compression phases, increasing power density, and allowing for the use of high water-to-fuel ratios, thereby improving engine efficiency and reducing CO2 emissions.
Implementation Method 1
high mass transfer rates
Implementation Method 2
intense mixing
Implementation Method 3
multiple localized combustion zones
Implementation Method 4
use of high water-to-fuel ratios
Data Source
AI summary
Many IC engine inefficiencies are linked to the relatively low mixture formation rates of current injection methods. Process intensification (PI) is excellent at high mixture formation rates, high mass transfer rates, and short residence times, therefore a wall integrated injection method and device featuring PI has been provided. It allows increased number of injection sites and interfacial surface area between fluid jets and the volume of the squash area, hence high mixture formation rates shorter Liquid Lengths and the use of micro nozzles to further intensify the mixing process by locally mixing fuel and oxidant. This allows high EGR and low compression ratios and better control of HCCI start of ignition. PI effectively achieves thermo and species stratification for extending the load range of the HCCI engine while permitting effective water addition for reciprocating and turbine for lower exhaust heat and less fuel burned hence less CO2 emissions.