Diesel Engine Injection Timing Control for Soot Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing diesel engine systems struggle to optimize the timing of after-injections to balance soot reduction and fuel efficiency, as the interval between main and after-injections is typically fixed and not adaptable to changing engine conditions, leading to suboptimal air utilization and energy conversion.
Innovation Solution
The diesel engine system adjusts the injection interval period based on temperature parameters, ensuring the after-injection timing aligns with the oxygen arrival timing, enhancing air utilization and allowing for earlier start times, thereby reducing soot generation and improving fuel efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the interval from the main injection to the after-injection is excessively shortened, then fuel efficiency is improved, but soot generation increases due to insufficient oxygen for combustion
Solution Approach 1:
The patent applies dynamics by making the injection interval variable rather than fixed. The control device dynamically adjusts the injection interval based on detected combustion properties from the main injection, allowing the system to adapt to changing combustion conditions and optimize both fuel efficiency and soot reduction in real-time
Solution Approach 2:
The patent changes the parameter of injection timing by adjusting the injection interval based on detected combustion properties. The control device modifies the timing parameters of the after-injection relative to the main injection, optimizing the balance between fuel efficiency and soot generation through parameter variation
2Object-generated harmful factors
If the interval from the main injection to the after-injection is fully lengthened to avoid soot generation, then soot production is reduced, but fuel efficiency deteriorates due to decreased work energy ratio
Solution Approach 1:
The patent implements feedback by using a detection device to monitor combustion properties resulting from the main injection, and then using this information to adjust the after-injection timing. This closed-loop feedback system enables real-time optimization of the injection interval to prevent soot while maintaining fuel efficiency
Solution Approach 2:
The system dynamically adjusts the injection interval based on detected combustion conditions rather than using a fixed interval, allowing optimal adaptation to varying engine operating conditions to balance soot reduction and fuel efficiency
3Object-generated harmful factors
If the after-injection timing is set earliest possible to improve air utilization and reduce soot, then air utilization factor is improved, but the timing becomes suboptimal when combustion conditions change
Solution Approach 1:
The control device uses feedback from the detection device that monitors combustion properties to dynamically adjust the after-injection timing. This ensures the system adapts to changing combustion conditions while maintaining optimal air utilization for soot reduction
Solution Approach 2:
The system changes the timing parameter of the after-injection based on detected combustion properties, allowing optimal adaptation to varying conditions while maintaining improved air utilization and reduced soot generation
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 adaptive approach effectively reduces soot production and enhances fuel efficiency by aligning the after-injection timing with optimal oxygen concentrations, improving energy conversion and maintaining appropriate fuel efficiency across varying engine conditions.
Implementation Method 1
an injector which sprays fuel containing diesel fuel into a combustion chamber
Implementation Method 2
a piston reciprocatably accommodated in the cylinder... fuel containing diesel fuel... into a combustion chamber
Data Source
Figure 1
Figure 2A~2B
Figure 3
AI summary
A diesel engine system is provided, which includes a piston having a cavity dented downwardly in a crown surface thereof and having a bottom part, a peripheral part dented so as to be convex radially outward, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in a cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of the fuel than the main injection is injected at a given timing later than the main injection in an expansion stroke. An injection interval period from an end of the main injection to a start of the after-injection is shorter as a temperature parameter related to a progress of a warmup of engine increases.