Pilot injection timing impact on combustion characteristics for a dual-fuel HCCI engine: experimental analysis

This paper presents an experimental investigation into the performance of a dual-fuel HCCI engine operating with syngas and diesel. The pilot diesel injection angle is identified as a critical parameter influencing combustion timing, torque output, and overall engine efficiency. Syngas, primarily composed of hydrogen (2) and carbon monoxide (CO), exhibits distinct combustion characteristics that significantly impact engine performance. The results reveal that average torque in dual-fuel operation follows a bell-shaped curve with respect to pilot injection timing, achieving peak torque within a specific range of injection angles. The study underscores the importance of optimizing the pilot injection angle based on the syngas flow rate to maximize engine performance. These findings demonstrate the potential of dual-fuel multi-cylinder HCCI engines to achieve enhanced efficiency while emphasizing the necessity for precise control of injection timing to optimize combustion processes and ensure stable operation.