Study on the impact of injection timing advance on the performance and emissions of a diesel engine fueled with a gasoline–diesel blend

Environmental concerns have increasingly driven industries worldwide, particularly the automotive sector, to address the challenges posed by pollutant emissions from internal combustion engines. Diesel engines, for instance, offer higher thermal efficiency than gasoline engines but remain major contributors to atmospheric pollution. Their emission characteristics are also strongly influenced by fuel properties. One promising approach to mitigating these emissions is the use of gasoline–diesel fuel blends. Due to their higher volatility and improved vaporization behavior, these blends promote more homogeneous air–fuel mixture formation, making them suitable for compression ignition engines. In addition, modifying key combustion parameters, most notably injection timing, has proven effective in influencing both emissions and combustion dynamics. Alongside injection pressure and intake oxygen concentration, injection timing plays a critical role in determining pollutant formation and the acoustic characteristics of the combustion process. This study examines the impact of a gasoline–diesel blend (G10) on the performance and emission characteristics of a diesel engine, with particular emphasis on the effects of varying injection timing. The aim is to experimentally evaluate how combining this blend with injection timing adjustments influences engine efficiency and emission output. The experimental results show that advancing injection timing improves torque, power output, and thermal efficiency while maintaining relatively low fuel consumption. Conversely, retarding injection timing is more effective in reducing pollutant emissions. The most effective strategy is delaying injection at 80% load and 3,500 rpm, which results in reductions of smoke density, NO X , and CO 2 by 77.34%, 34.45%, and 11.34%, respectively. Performance also improves, with torque increasing by 26.25%, power by 14.52%, and specific fuel consumption decreasing by 9.76%. Although a trade-off exists between optimizing performance and minimizing emissions, the findings indicate that strategic calibration of injection parameters can achieve a balanced compromise between both goals. In conclusion, adjusting injection timing emerges as a viable technique for reducing pollutant emissions without significantly compromising—and potentially even enhancing—engine performance.