Cylinder Balancing via In-Cylinder Pressure Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for cylinder balancing in internal combustion engines are inaccurate due to variations in cylinder-to-cylinder exhaust temperatures, leading to performance degradation and premature wear, as they do not accurately account for actual cylinder conditions.
Innovation Solution
A method that involves injecting different fuels into the cylinders to obtain exhaust temperature profiles, allowing for adjustments in injection quantity and timing based on the differences between these profiles to achieve a more balanced engine operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If cylinder balancing is performed using exhaust temperature measurements, then cylinder power balance can be improved, but measurement accuracy deteriorates due to sensor variations and mounting differences
Solution Approach 1:
The patent changes the measurement parameter from exhaust temperature to in-cylinder pressure. Pressure sensors mounted in the cylinder head directly measure combustion pressure, providing more accurate and consistent data across all cylinders without being affected by exhaust system variations or sensor mounting differences.
Solution Approach 2:
The patent introduces an intermediary calculation method that uses pressure data to derive end-gas temperature and heat release rate. This intermediary approach allows indirect measurement of combustion characteristics that are more representative of actual cylinder conditions while avoiding direct temperature measurement issues.
2Reliability
If fuel quantity is adjusted to balance cylinders, then power distribution improves, but knock limits may be approached leading to performance degradation
Solution Approach 1:
The patent implements feedback control using in-cylinder pressure measurements to monitor combustion quality and knock tendency. The system continuously adjusts fuel injection based on real-time pressure data, ensuring cylinders are balanced without exceeding knock limits, thereby maintaining optimal engine performance.
Solution Approach 2:
The patent performs preliminary assessment of cylinder combustion characteristics using pressure data before making fuel adjustments. This allows prediction of potential knock conditions and prevents excessive fuel reduction that would cause knock, enabling safer and more effective cylinder balancing.
3Productivity
If unbalanced engine operation continues, then immediate performance impact is avoided, but premature wear and decreased reliability occur over time
Solution Approach 1:
The patent performs preliminary diagnosis of cylinder balance issues using pressure sensors before significant wear occurs. By detecting and correcting imbalances early in the engine's operation, the system prevents the cumulative damage that would lead to premature component wear while maintaining continuous operation.
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 results in a more balanced power profile and improved engine operation by closely matching dual fuel exhaust temperature distribution to diesel-only distribution, reducing wear and increasing engine longevity.
Implementation Method 1
injecting a first fuel into a plurality of cylinders of the internal combustion engine
Implementation Method 2
obtaining a first fuel exhaust temperature profile, during the first fuel operation
Data Source
AI summary
A method of adjusting operation of an internal combustion engine includes injecting fuel into cylinders of the internal combustion engine (first fuel operation); obtaining a first fuel exhaust temperature profile during the first fuel operation; injecting two fuels into the cylinders in a duel fuel operation; obtaining a duel fuel exhaust temperature profile; and adjusting the injection quantity and/or an injection timing of one fuel in a cylinder(s), based on a difference between the first fuel exhaust temperature profile and the duel fuel exhaust temperature profile. Other methods of operating with single fuel and using sensors other than exhaust temperature sensors are disclosed.