Development and Validation of a Modeling and Calibration Method for Diesel-Like Multistage Combustion Based On a...

Area of Science:

• Mechanical Engineering
• Combustion Science
• Automotive Engineering

Background:

• Stringent fuel consumption and emission regulations necessitate advanced diesel engine control strategies.
• Accurate real-time prediction of in-cylinder combustion is crucial for optimizing diesel engine performance.
• Existing models may lack the precision or real-time capability required for multiphase diesel combustion prediction.

Purpose of the Study:

• To present a modified multi-Wiebe function for precise, real-time prediction of multiphase diesel combustion.
• To introduce a novel calibration method, "backward-stepwise recursion," for efficient model parameterization.
• To validate the model's performance across various load conditions in a prototype diesel engine.

Main Methods:

• Development of a modified multi-Wiebe function with a simplified parameter structure (center point θ50 and form factor m).
• Implementation of a "backward-stepwise recursion" calibration method to fit heat release rate data from tail to pre-combustion stages.
• Application and testing of the model on measured heat release rate data from a single-cylinder diesel engine (15%-100% load).

Main Results:

• The modified multi-Wiebe function accurately captures measured heat release rate characteristics.
• The "backward-stepwise recursion" method efficiently calibrates the function, avoiding parameter ambiguity.
• The model demonstrates good accordance in heat release prediction across all tested load conditions.

Conclusions:

• The proposed modified multi-Wiebe function provides accurate real-time combustion prediction for diesel engines.
• The novel calibration method is effective for various combustion scenarios, including dual-fuel applications.
• The model is suitable for integration into engine control units for enhanced operational performance.