Internal Combustion Engine Pre-Ignition Detection via Acceleration Sensor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for internal combustion engines fail to effectively prevent pre-ignitions until after they have occurred, leading to engine damage and inefficiency.
Innovation Solution
A method that uses an acceleration sensor to measure combustion noise levels, activating a safety operating mode to reduce compression in the combustion chamber if the noise amplitude exceeds a certain threshold multiple times, thereby preventing pre-ignitions by modifying valve timings, mixture enrichment, and pressure limitations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If knock reduction measures are initiated only after knocking occurs, then engine knock can be reduced, but pre-ignitions cannot be prevented in advance leading to engine damage
Solution Approach 1:
The system performs preliminary action by detecting pre-ignition conditions through noise level monitoring and amplitude analysis before actual pre-ignition damage occurs. When the amplitude limiting value is exceeded n times, the control system proactively activates the safety operating mode to reduce effective compression, preventing pre-ignition damage before it happens rather than reacting after knock occurs
Solution Approach 2:
The system implements feedback by continuously monitoring combustion noise levels and analyzing amplitude patterns. The control system uses feedback from the acceleration sensor to detect when the amplitude limiting value is exceeded n times, and automatically adjusts compression timing by modifying valve timings or injection timing based on this feedback to prevent pre-ignition damage
2Reliability
If sustained measures to reduce effective compression are activated, then pre-ignitions are prevented and engine runtime is extended, but engine power output is reduced
Solution Approach 1:
The system applies dynamics by making the compression timing adjustable rather than fixed. The control system dynamically modifies valve timings or injection timing to reduce effective compression when pre-ignition risk is detected, and can restore normal timing when the condition clears, allowing the engine to operate at full power under normal conditions while preventing damage when needed
Solution Approach 2:
The system changes parameters by adjusting the effective compression ratio through timing modifications. When pre-ignition conditions are detected (amplitude limiting value exceeded n times), the control system changes the timing parameters of valve operation or fuel injection to reduce compression, thereby preventing pre-ignition while managing the trade-off with power output
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 sustains measures to prevent pre-ignitions, reducing mechanical stress and extending engine runtime by lowering combustion pressures and temperatures, even with low-quality fuels, while maintaining maximum torque.
Implementation Method 1
a noise level of the combustion process is measured by means of an acceleration sensor
Data Source
AI summary
A method for avoiding pre-ignitions during the operation of an internal combustion engine includes measuring a noise level of a combustion process using an acceleration sensor. An amplitude an amplitude of the measured noise level is measured to detect pre-ignitions. If, in the analysis, the measured noise level of a combustion cycle exceeds a limiting value n times, a safety operating mode of the internal combustion engine for reducing an effecting compression in the combustion chamber is activated. The safety operating mode is maintained if exceeding of the amplitude limiting value is also detected in subsequent combustion cycles of the internal combustion engine.